def log_likelihood_single_fix_hill(measurements, doses, theta):
# using hill = 1, but not bothering to assign it
pIC50, sigma = theta
IC50 = dr.pic50_to_ic50(pIC50)
return -len(measurements) * np.log(sigma) - np.sum(
(measurements - dr.dose_response_model(doses, 1, IC50))**
2) / (2. * sigma**2)
def log_likelihood_single(measurements, doses, theta):
hill = theta[0]
pIC50 = theta[1]
sigma = theta[2]
IC50 = dr.pic50_to_ic50(pIC50)
return -len(measurements) * np.log(sigma) - np.sum(
(measurements - dr.dose_response_model(doses, hill, IC50))**
2) / (2. * sigma**2)
def sum_of_square_diffs(params, model):
if model == 1:
pic50 = params[0]
hill = 1
elif model == 2:
pic50, hill = params
if hill <= hill_lower or hill > hill_upper or pic50 <= pic50_lower:
return 1e9
else:
predicted = dr.dose_response_model(concs, hill, dr.pic50_to_ic50(pic50))
return np.sum((responses-predicted)**2)
def sum_of_square_diffs(params, model):
if model == 1:
pic50 = params[0]
hill = 1
elif model == 2:
pic50, hill = params
if hill <= hill_lower or hill > hill_upper or pic50 <= pic50_lower:
return 1e9
else:
predicted = dr.dose_response_model(concs, hill,
dr.pic50_to_ic50(pic50))
return np.sum((responses - predicted)**2)
def log_data_likelihood(hill_is, pic50_is, sigma, experiments):
Ne = len(experiments)
answer = 0.
for i in range(Ne):
ic50 = dr.pic50_to_ic50(pic50_is[i])
concs = experiments[i][:, 0]
num_expt_pts = len(concs)
data = experiments[i][:, 1]
model_responses = dr.dose_response_model(concs, hill_is[i], ic50)
exp_bit = np.sum((data - model_responses)**2) / (2 * sigma**2)
# assuming noise Normal is truncated at 0 and 100
truncated_scale = np.sum(
np.log(
st.norm.cdf(100, model_responses, sigma) -
st.norm.cdf(0, model_responses, sigma)))
answer -= (num_expt_pts * np.log(sigma) + exp_bit + truncated_scale)
if np.isnan(answer):
print "NaN from log_data_likelihood!"
print "hill_is =", hill_is
print "pic50_is =", pic50_is
print "sigma =", sigma
sys.exit()
return answer
def do_plot(drug_channel):
global concs, responses
fig = plt.figure(figsize=(5, 8))
axes = {}
axes[1] = fig.add_subplot(211)
axes[2] = fig.add_subplot(212) #, sharey=axes[1])
fsize = 14
for model in xrange(1, num_models + 1):
dr.define_model(model)
drug, channel = drug_channel
num_expts, experiment_numbers, experiments = dr.load_crumb_data(
drug, channel)
figs_dir = dr.drug_channel_figs_dir(drug, channel)
concs = np.array([])
responses = np.array([])
for i in xrange(num_expts):
concs = np.concatenate((concs, experiments[i][:, 0]))
responses = np.concatenate((responses, experiments[i][:, 1]))
if model == 1:
x0 = np.ones(2)
sigma0 = 0.1
elif model == 2:
x0 = np.copy([pic50, hill])
sigma0 = 0.01
#x0[0] = 6.9
opts = cma.CMAOptions()
es = cma.CMAEvolutionStrategy(x0, sigma0, opts)
while not es.stop():
X = es.ask()
f_vals = [sum_of_square_diffs(x, model) for x in X]
es.tell(X, f_vals)
es.disp()
res = es.result()
ss = res[1]
pic50, hill = res[0]
if model == 1:
hill = 1
conc_min = np.min(concs)
conc_max = np.max(concs)
num_pts = 501
x_range = np.logspace(
int(np.log10(conc_min)) - 1,
int(np.log10(conc_max)) + 2, num_pts)
predicted = dr.dose_response_model(x_range, hill,
dr.pic50_to_ic50(pic50))
#fig = plt.figure(figsize=(5,4))
#ax = fig.add_subplot(111)
axes[model].grid()
axes[model].set_xscale('log')
axes[model].set_ylim(0, 100)
axes[model].set_ylabel(r"% {} block".format(channel), fontsize=fsize)
axes[model].set_xlabel(r"{} concentration ($\mu$M)".format(drug),
fontsize=fsize)
axes[model].plot(x_range,
predicted,
color='blue',
lw=2,
label="Best fit")
axes[model].plot(concs,
responses,
'o',
color='orange',
ms=10,
label="Expt data")
axes[model].legend(loc=2)
axes[model].set_title("$M_{}, pIC50 = {}, Hill = {}, SS = {}$".format(
model, round(pic50, 2), round(hill, 2), round(ss, 2)),
fontsize=fsize)
#axes[2].set_yticklabels([])
fig.tight_layout()
#fig.savefig(figs_dir+"{}_{}_model_{}_best_fit.png".format(drug,channel,model))
fig.savefig(all_figs_dir + "{}_{}_best_fits.png".format(drug, channel))
fig.savefig(figs_dir + "{}_{}_best_fit.pdf".format(drug, channel))
plt.close()
def run_single_level(drug_channel):
drug, channel = drug_channel
print "\n\n{} + {}\n\n".format(drug, channel)
seed = 100
try:
num_expts, experiment_numbers, experiments = dr.load_crumb_data(
drug, channel)
except:
print "Problem loading data, guessing there are no entries for {} + {} --- skipping".format(
drug, channel)
return None
drug, channel, chain_file, images_dir = dr.nonhierarchical_chain_file_and_figs_dir(
args.model, drug, channel, temperature)
concs = np.array([])
responses = np.array([])
for i in xrange(num_expts):
concs = np.concatenate((concs, experiments[i][:, 0]))
responses = np.concatenate((responses, experiments[i][:, 1]))
if np.any(np.isnan(responses)):
print "Skipping {} because of empty responses / missing data".format(
drug_channel)
return None
#print experiments
#print concs
#print responses
where_r_0 = responses == 0
where_r_100 = responses == 100
where_r_other = (0 < responses) & (responses < 100)
#print "where_r_0:", where_r_0
#print "where_r_100:", where_r_100
#print "where_r_other:", where_r_other
pi_bit = dr.compute_pi_bit_of_log_likelihood(where_r_other)
# plot priors
for i in xrange(num_params):
fig = plt.figure(figsize=(4, 3))
ax = fig.add_subplot(111)
ax.grid()
ax.plot(dr.prior_xs[i], dr.prior_pdfs[i], color='blue', lw=2)
ax.set_xlabel(dr.labels[i])
ax.set_ylabel("Prior pdf")
fig.tight_layout()
fig.savefig(images_dir + dr.file_labels[i] + "_prior_pdf.pdf")
plt.close()
start = time.time()
sigma0 = 0.1
opts = cma.CMAOptions()
opts['seed'] = seed
if args.model == 1:
#x0 = np.array([2.5, 3.])
x0 = np.array([2.5, 1.])
es = cma.CMAEvolutionStrategy(x0, sigma0, opts)
while not es.stop():
X = es.ask()
#es.tell(X, [-dr.log_target(responses, where_r_0, where_r_100, where_r_other, concs, x**2 + [dr.pic50_exp_lower,dr.sigma_uniform_lower], temperature, pi_bit) for x in X])
es.tell(X, [
sum_of_square_diffs([x[0]**2 + dr.pic50_exp_lower, 1.], concs,
responses) for x in X
])
es.disp()
res = es.result
#pic50_cur, sigma_cur = res[0]**2 + [dr.pic50_exp_lower, dr.sigma_uniform_lower]
pic50_cur = res[0][0]**2 + dr.pic50_exp_lower
hill_cur = 1
elif args.model == 2:
#x0 = np.array([2.5, 1., 3.])
x0 = np.array([2.5, 1.])
es = cma.CMAEvolutionStrategy(x0, sigma0, opts)
while not es.stop():
X = es.ask()
#es.tell(X, [-dr.log_target(responses, where_r_0, where_r_100, where_r_other, concs, x**2 + [dr.pic50_exp_lower, dr.hill_uniform_lower, dr.sigma_uniform_lower], temperature, pi_bit) for x in X])
es.tell(X, [
sum_of_square_diffs(
x**2 + [dr.pic50_exp_lower, dr.hill_uniform_lower], concs,
responses) for x in X
])
es.disp()
res = es.result
#pic50_cur, hill_cur, sigma_cur = res[0]**2 + [dr.pic50_exp_lower, dr.hill_uniform_lower, dr.sigma_uniform_lower]
pic50_cur, hill_cur = res[0]**2 + [
dr.pic50_exp_lower, dr.hill_uniform_lower
]
sigma_cur = initial_sigma(len(responses), res[1])
#print "sigma_cur:", sigma_cur
if args.model == 1:
theta_cur = np.array([pic50_cur, sigma_cur])
elif args.model == 2:
theta_cur = np.array([pic50_cur, hill_cur, sigma_cur])
#print "theta_cur:", theta_cur
best_params_file = images_dir + "{}_{}_best_fit_params.txt".format(
drug, channel)
with open(best_params_file, "w") as outfile:
outfile.write("# CMA-ES best fit params\n")
if args.model == 1:
outfile.write("# pIC50, sigma, (Hill=1, not included)\n")
elif args.model == 2:
outfile.write("# pIC50, Hill, sigma\n")
np.savetxt(outfile, [theta_cur])
proposal_scale = 0.05
mean_estimate = np.copy(theta_cur)
cov_estimate = proposal_scale * np.diag(np.copy(np.abs(theta_cur)))
cmaes_ll = dr.log_target(responses, where_r_0, where_r_100, where_r_other,
concs, theta_cur, temperature, pi_bit)
#print "cmaes_ll:", cmaes_ll
best_fit_fig = plt.figure(figsize=(5, 4))
best_fit_ax = best_fit_fig.add_subplot(111)
best_fit_ax.set_xscale('log')
best_fit_ax.grid()
if np.min(concs) == 0:
plot_lower_lim = int(np.log10(np.min(concs[np.nonzero(concs)]))) - 2
else:
plot_lower_lim = int(np.log10(np.min(concs))) - 2
plot_upper_lim = int(np.log10(np.max(concs))) + 2
best_fit_ax.set_xlim(10**plot_lower_lim, 10**plot_upper_lim)
best_fit_ax.set_ylim(0, 100)
num_x_pts = 1001
x_range = np.logspace(plot_lower_lim, plot_upper_lim, num_x_pts)
best_fit_curve = dr.dose_response_model(x_range, hill_cur,
dr.pic50_to_ic50(pic50_cur))
best_fit_ax.plot(x_range, best_fit_curve, label='Best fit', lw=2)
best_fit_ax.set_ylabel('% {} block'.format(channel))
best_fit_ax.set_xlabel(r'{} concentration ($\mu$M)'.format(drug))
best_fit_ax.set_title(r'$pIC50 = {}, Hill = {}; SS = {}$'.format(
np.round(pic50_cur, 2), np.round(hill_cur, 2), round(res[1], 2)))
best_fit_ax.plot(concs,
responses,
"o",
color='orange',
ms=10,
label='Data',
zorder=10)
best_fit_ax.legend(loc=2)
best_fit_fig.tight_layout()
best_fit_fig.savefig(
images_dir +
'{}_{}_model_{}_CMA-ES_best_fit.png'.format(drug, channel, args.model))
best_fit_fig.savefig(
images_dir +
'{}_{}_model_{}_CMA-ES_best_fit.pdf'.format(drug, channel, args.model))
plt.close()
if args.best_fit_only:
print "\nStopping {}+{} after doing and plotting best fit\n".format(
drug, channel)
return None
# let MCMC look around for a bit before adaptive covariance matrix
# same rule (100*dimension) as in hierarchical case
when_to_adapt = 1000 * num_params
log_target_cur = dr.log_target(responses, where_r_0, where_r_100,
where_r_other, concs, theta_cur,
temperature, pi_bit)
#print "initial log_target_cur =", log_target_cur
# effectively step size, scales covariance matrix
loga = 0.
# what fraction of proposed samples are being accepted into the chain
acceptance = 0.
# what fraction of samples we WANT accepted into the chain
# loga updates itself to try to make this dream come true
target_acceptance = 0.25
total_iterations = args.iterations
thinning = args.thinning
assert (total_iterations % thinning == 0)
# how often to print a little status message
status_when = total_iterations / 20
saved_iterations = total_iterations / thinning + 1
# also want to store log-target value at each iteration
chain = np.zeros((saved_iterations, num_params + 1))
chain[0, :] = np.concatenate((np.copy(theta_cur), [log_target_cur]))
#print chain[0]
#print "concs:", concs
#print "responses:", responses
# for reproducible results, otherwise select a new random seed
seed = 25
npr.seed(seed)
# MCMC!
t = 1
start = time.time()
while t <= total_iterations:
theta_star = npr.multivariate_normal(theta_cur,
np.exp(loga) * cov_estimate)
accepted = 0
log_target_star = dr.log_target(responses, where_r_0, where_r_100,
where_r_other, concs, theta_star,
temperature, pi_bit)
accept_prob = npr.rand()
if (np.log(accept_prob) < log_target_star - log_target_cur):
theta_cur = theta_star
log_target_cur = log_target_star
accepted = 1
acceptance = ((t - 1.) * acceptance + accepted) / t
if (t > when_to_adapt):
s = t - when_to_adapt
gamma_s = 1 / (s + 1)**0.6
temp_covariance_bit = np.array([theta_cur - mean_estimate])
cov_estimate = (1 - gamma_s) * cov_estimate + gamma_s * np.dot(
np.transpose(temp_covariance_bit), temp_covariance_bit)
mean_estimate = (1 - gamma_s) * mean_estimate + gamma_s * theta_cur
loga += gamma_s * (accepted - target_acceptance)
if (t % thinning == 0):
chain[t / thinning, :] = np.concatenate(
(np.copy(theta_cur), [log_target_cur]))
if (t % status_when == 0):
#print "{} / {}".format(t/status_when,total_iterations/status_when)
time_taken_so_far = time.time() - start
estimated_time_left = time_taken_so_far / t * (total_iterations -
t)
#print "Time taken: {} s = {} min".format(np.round(time_taken_so_far,1),np.round(time_taken_so_far/60,2))
#print "acceptance = {}".format(np.round(acceptance,5))
#print "Estimated time remaining: {} s = {} min".format(np.round(estimated_time_left,1),np.round(estimated_time_left/60,2))
t += 1
#print "\nTime taken to do {} MCMC iterations: {} s\n".format(total_iterations, time.time()-start)
#print "Final iteration:", chain[-1,:], "\n"
burn_fraction = args.burn_in_fraction
burn = saved_iterations / burn_fraction
chain = chain[burn:, :] # remove burn-in before saving
with open(chain_file, 'w') as outfile:
outfile.write(
'# Nonhierarchical MCMC output for {} + {}: (Hill,pIC50,sigma,log-target)\n'
.format(drug, channel))
np.savetxt(outfile, chain)
best_ll_index = np.argmax(chain[:, num_params])
best_ll_row = chain[best_ll_index, :]
#print "Best log-likelihood:", "\n", best_ll_row
figs = []
axs = []
# plot all marginal posterior distributions
for i in range(num_params):
figs.append(plt.figure())
axs.append([])
axs[i].append(figs[i].add_subplot(211))
axs[i][0].hist(chain[:, i],
bins=40,
normed=True,
color='blue',
edgecolor='blue')
axs[i][0].legend()
axs[i][0].set_title("MCMC marginal distributions")
axs[i][0].set_ylabel("Normalised frequency")
axs[i][0].grid()
plt.setp(axs[i][0].get_xticklabels(), visible=False)
axs[i].append(figs[i].add_subplot(212, sharex=axs[i][0]))
axs[i][1].plot(chain[:, i], range(burn, saved_iterations))
axs[i][1].invert_yaxis()
axs[i][1].set_xlabel(dr.labels[i])
axs[i][1].set_ylabel('Saved MCMC iteration')
axs[i][1].grid()
figs[i].tight_layout()
figs[i].savefig(images_dir + '{}_{}_model_{}_{}_marginal.png'.format(
drug, channel, args.model, dr.file_labels[i]))
plt.close()
# plot log-target path
fig2 = plt.figure()
ax3 = fig2.add_subplot(111)
ax3.plot(range(burn, saved_iterations), chain[:, -1])
ax3.set_xlabel('MCMC iteration')
ax3.set_ylabel('log-target')
ax3.grid()
fig2.tight_layout()
fig2.savefig(images_dir + 'log_target.png')
plt.close()
# plot scatterplot matrix of posterior(s)
colormin, colormax = 1e9, 0
norm = matplotlib.colors.Normalize(vmin=5, vmax=10)
hidden_labels = []
count = 0
# there's probably a better way to do this
# I plot all the histograms to normalize the colours, in an attempt to give a better comparison between the pairwise plots
while count < 2:
axes = {}
matrix_fig = plt.figure(figsize=(3 * num_params, 3 * num_params))
for i in range(num_params):
for j in range(i + 1):
ij = str(i) + str(j)
subplot_position = num_params * i + j + 1
if i == j:
axes[ij] = matrix_fig.add_subplot(num_params, num_params,
subplot_position)
axes[ij].hist(chain[:, i],
bins=50,
normed=True,
color='blue',
edgecolor='blue')
elif j == 0: # this column shares x-axis with top-left
axes[ij] = matrix_fig.add_subplot(num_params,
num_params,
subplot_position,
sharex=axes["00"])
counts, xedges, yedges, Image = axes[ij].hist2d(
chain[:, j],
chain[:, i],
cmap='hot_r',
bins=50,
norm=norm)
maxcounts = np.amax(counts)
if maxcounts > colormax:
colormax = maxcounts
mincounts = np.amin(counts)
if mincounts < colormin:
colormin = mincounts
else:
axes[ij] = matrix_fig.add_subplot(
num_params,
num_params,
subplot_position,
sharex=axes[str(j) + str(j)],
sharey=axes[str(i) + "0"])
counts, xedges, yedges, Image = axes[ij].hist2d(
chain[:, j],
chain[:, i],
cmap='hot_r',
bins=50,
norm=norm)
maxcounts = np.amax(counts)
if maxcounts > colormax:
colormax = maxcounts
mincounts = np.amin(counts)
if mincounts < colormin:
colormin = mincounts
axes[ij].xaxis.grid()
if (i != j):
axes[ij].yaxis.grid()
if i != num_params - 1:
hidden_labels.append(axes[ij].get_xticklabels())
if j != 0:
hidden_labels.append(axes[ij].get_yticklabels())
if i == j == 0:
hidden_labels.append(axes[ij].get_yticklabels())
if i == num_params - 1:
axes[str(i) + str(j)].set_xlabel(dr.labels[j], fontsize=18)
if j == 0 and i > 0:
axes[str(i) + str(j)].set_ylabel(dr.labels[i], fontsize=18)
plt.xticks(rotation=30)
norm = matplotlib.colors.Normalize(vmin=colormin, vmax=colormax)
count += 1
plt.setp(hidden_labels, visible=False)
matrix_fig.tight_layout()
matrix_fig.savefig(images_dir +
"{}_{}_model_{}_scatterplot_matrix.png".format(
drug, channel, args.model))
matrix_fig.savefig(images_dir +
"{}_{}_model_{}_scatterplot_matrix.pdf".format(
drug, channel, args.model))
plt.close()
print "\n\n{} + {} complete!\n\n".format(drug, channel)
return None
def run_hierarchical(drug_channel):
global pic50_prior
pic50_prior = [
-2.
] # bad way to deal with sum_of_square_diffs in hierarchical case
global pic50_hill_lowers
pic50_hill_priors_lowers = np.array([-2., 0.])
drug, channel = drug_channel
print "\n\n{} + {}\n\n".format(drug, channel)
# for reproducible results, otherwise choose a different seed
seed = 1
num_expts, experiment_numbers, experiments = dr.load_crumb_data(
drug, channel)
if (0 < (args.num_expts) < num_expts):
num_expts = args.num_expts
experiment_numbers = [x for x in experiment_numbers[:num_expts]]
experiments = [x for x in experiments[:num_expts]]
elif (args.num_expts == 0):
print "Fitting to all datasets\n"
else:
print "You've asked to fit to an impossible number of experiments for {} + {}\n".format(
drug, channel)
print "Therefore proceeding with all experiments in the input data file\n"
# set up where to save chains and figures to
# also renames anything with a '/' in its name and changes it to a '_'
drug, channel, output_dir, chain_dir, figs_dir, chain_file = dr.hierarchical_output_dirs_and_chain_file(
drug, channel, num_expts)
best_fits = []
for expt in experiment_numbers:
start = time.time()
x0 = np.array([2.5, 1.]) # (pIC50,Hill) not fitting sigma by CMA-ES
sigma0 = 0.1
opts = cma.CMAOptions()
opts['seed'] = expt
es = cma.CMAEvolutionStrategy(x0, sigma0, opts)
while not es.stop():
X = es.ask()
es.tell(X, [
sum_of_square_diffs(x**2 + pic50_hill_priors_lowers,
experiments[expt][:, 0],
experiments[expt][:, 1]) for x in X
])
res = es.result
best_fits.append(
np.concatenate(
(res[0]**2 + pic50_hill_priors_lowers,
[initial_sigma(len(experiments[expt][:, 0]), res[1])])))
best_fits = np.array(best_fits)
fig = plt.figure(figsize=(5.5, 4.5))
ax = fig.add_subplot(111)
ax.set_xscale('log')
xmin = 1000
xmax = -1000
for expt in experiments:
a = np.min(expt[:, 0])
b = np.max(expt[:, 0])
if a < xmin:
xmin = a
if b > xmax:
xmax = b
xmin = int(np.log10(xmin)) - 1
xmax = int(np.log10(xmax)) + 3
num_x_pts = 101
x = np.logspace(xmin, xmax, num_x_pts)
# from http://colorbrewer2.org
colors = [
'#a6cee3', '#1f78b4', '#b2df8a', '#33a02c', '#fb9a99', '#e31a1c',
'#fdbf6f', '#ff7f00', '#cab2d6', '#6a3d9a', '#ffff99', '#b15928'
]
skip_best_fits_plot = False
if (num_expts > len(colors)):
skip_best_fits_plot = True
print "Not enough colours to print all experiments' best fits, so skipping that"
if (not skip_best_fits_plot):
for expt in experiment_numbers:
print "best_fits:", best_fits
print "best_fits[{}]:".format(expt), best_fits[expt]
ax.plot(x,
dr.dose_response_model(
x, best_fits[expt, 1],
dr.pic50_to_ic50(best_fits[expt, 0])),
color=colors[expt],
lw=2)
ax.scatter(experiments[expt][:, 0],
experiments[expt][:, 1],
label='Expt {}'.format(expt + 1),
color=colors[expt],
s=100)
ax.set_ylim(0, 100)
ax.set_xlim(min(x), max(x))
ax.set_xlabel(r'{} concentration ($\mu$M)'.format(drug))
ax.set_ylabel('% {} block'.format(channel))
ax.legend(loc=2)
ax.grid()
ax.set_title('Hills = {}\nIC50s = {}'.format(
[round(best_fits[expt, 1], 1) for expt in experiment_numbers], [
round(dr.pic50_to_ic50(best_fits[expt, 0]), 1)
for expt in experiment_numbers
]))
fig.tight_layout()
fig.savefig(figs_dir +
'{}_{}_cma-es_best_fits.png'.format(drug, channel))
fig.savefig(figs_dir +
'{}_{}_cma-es_best_fits.pdf'.format(drug, channel))
plt.close()
locs = np.array([0., 2., -4, 0.01,
dr.sigma_loc]) # lower bounds for alpha,beta,mu,s,sigma
sigma_cur = np.mean(best_fits[:, -1])
if (sigma_cur <= locs[3]):
sigma_cur = locs[3] + 0.1
print "sigma_cur =", sigma_cur
# find initial alpha and beta values by fitting log-logistic distribution to best fits
# there is an inbuilt fit function, but I found it to be unreliable for some reason
x0 = np.array([0.5, 0.5])
sigma0 = 0.1
opts = cma.CMAOptions()
opts['seed'] = 1
es = cma.CMAEvolutionStrategy(x0, sigma0, opts)
while not es.stop():
X = es.ask()
es.tell(X, [
-np.product(st.fisk.pdf(best_fits[:, 1], c=x[1], scale=x[0],
loc=0)) for x in X
])
res = es.result
alpha_cur, beta_cur = np.copy(res[0])
if alpha_cur <= locs[0]:
alpha_cur = locs[0] + 0.1
if beta_cur <= locs[1]:
beta_cur = locs[1] + 0.1
# here I have used the fit function, for some reason this one worked more consitently
# but again, the starting point for MCMC is not too important
# a bad starting position can increase the time you have to run MCMC for to get a "converged" output
# at worst, it can get stuck in a local optimum, but we haven't found this to be a problem yet
mu_cur, s_cur = st.logistic.fit(best_fits[:, 0])
if mu_cur <= locs[2]:
mu_cur = locs[2] + 0.1
if s_cur <= locs[3]:
s_cur = locs[3] + 0.1
first_iteration = np.concatenate(
([alpha_cur, beta_cur, mu_cur,
s_cur], best_fits[:, :-1].flatten(), [sigma_cur]))
print "first mcmc iteration:\n", first_iteration
# these are the numbers taken straight from Elkins (see paper for reference)
elkins_hill_alphas = np.array([
1.188, 1.744, 1.530, 0.930, 0.605, 1.325, 1.179, 0.979, 1.790, 1.708,
1.586, 1.469, 1.429, 1.127, 1.011, 1.318, 1.063
])
elkins_hill_betas = 1. / np.array([
0.0835, 0.1983, 0.2089, 0.1529, 0.1206, 0.2386, 0.2213, 0.2263, 0.1784,
0.1544, 0.2486, 0.2031, 0.2025, 0.1510, 0.1837, 0.1677, 0.0862
])
elkins_pic50_mus = np.array([
5.235, 5.765, 6.060, 5.315, 5.571, 7.378, 7.248, 5.249, 6.408, 5.625,
7.321, 6.852, 6.169, 6.217, 5.927, 7.414, 4.860
])
elkins_pic50_sigmas = np.array([
0.0760, 0.1388, 0.1459, 0.2044, 0.1597, 0.2216, 0.1856, 0.1560, 0.1034,
0.1033, 0.1914, 0.1498, 0.1464, 0.1053, 0.1342, 0.1808, 0.0860
])
elkins = [
elkins_hill_alphas, elkins_hill_betas, elkins_pic50_mus,
elkins_pic50_sigmas
]
# building Gamma prior distributions for alpha,beta,mu,s(,sigma, but sigma not from elkins)
# wide enough to cover Elkins values and allow room for extra variation
alpha_mode = np.mean(elkins_hill_alphas)
beta_mode = np.mean(elkins_hill_betas)
mu_mode = np.mean(elkins_pic50_mus)
s_mode = np.mean(elkins_pic50_sigmas)
sigma_mode = dr.sigma_mode
modes = np.array([alpha_mode, beta_mode - 2., mu_mode, s_mode, sigma_mode])
print "modes:", modes
# designed for priors to have modes at means of elkins data, but width is more important
shapes = np.array([5., 2.5, 7.5, 2.5,
dr.sigma_shape]) # must all be greater than 1
scales = (modes - locs) / (shapes - 1.)
labels = [r'$\alpha$', r'$\beta$', r'$\mu$', r'$s$', r'$\sigma$']
file_labels = ['alpha', 'beta', 'mu', 's', 'sigma']
# ranges to plot priors
mins = [0, 0, -5, 0, 0]
maxs = [8, 22, 20, 2, 25]
prior_xs = []
priors = []
total_axes = (6, 4)
fig = plt.figure(figsize=(6, 7))
for i in range(len(labels) - 1):
if i == 0:
axloc = (0, 0)
elif i == 1:
axloc = (0, 2)
elif i == 2:
axloc = (2, 0)
elif i == 3:
axloc = (2, 2)
ax = plt.subplot2grid(total_axes, axloc, colspan=2, rowspan=2)
x_prior = np.linspace(mins[i], maxs[i], 501)
prior = st.gamma.pdf(x_prior,
a=shapes[i],
scale=scales[i],
loc=locs[i])
prior_xs.append(x_prior)
priors.append(prior)
ax.plot(x_prior, prior, label='Gamma prior', lw=2)
ax.set_xlabel(labels[i])
ax.set_ylabel('Probability density')
ax.set_xlim(mins[i], maxs[i])
ax.grid()
priormax = np.max(prior)
hist, bin_edges = np.histogram(elkins[i], bins=10)
histmax = np.max(hist)
w = bin_edges[1] - bin_edges[0]
bin_centers = (bin_edges[:-1] + bin_edges[1:]) / 2.
# scaled histogram just to fit plot better, but this scaling doesn't matter
ax.bar(bin_edges[:-1],
priormax / histmax * hist,
width=w,
color='gray',
edgecolor='grey')
i = len(labels) - 1
ax = plt.subplot2grid(total_axes, (4, 1), colspan=2, rowspan=2)
x_prior = np.linspace(mins[i], maxs[i], 501)
prior = st.gamma.pdf(x_prior, a=shapes[i], scale=scales[i], loc=locs[i])
ax.plot(x_prior, prior, label='Gamma prior', lw=2)
prior_xs.append(x_prior)
priors.append(prior)
ax.set_xlabel(labels[i])
ax.set_ylabel('Probability density')
ax.set_xlim(mins[i], maxs[i])
ax.grid()
fig.tight_layout()
fig.savefig(figs_dir + 'all_prior_distributions.png')
fig.savefig(figs_dir + 'all_prior_distributions.pdf')
plt.close()
#sys.exit # uncomment this if you just want to plot the priors and then quit
# create/wipe MCMC output file
with open(chain_file, 'w') as outfile:
outfile.write(
"# Hill ~ log-logistic(alpha,beta), pIC50 ~ logistic(mu,s)\n")
outfile.write(
"# alpha, beta, mu, s, hill_1, pic50_1, hill_2, pic50_2, ..., hill_Ne, pic50_Ne, sigma\n"
) # this is the order of parameters stored in the chain
# have to choose initial covariance matrix for proposal distribution
# we set it to a diagonal with entries scaled to the initial parameter values
first_cov = np.diag(0.01 * np.abs(first_iteration))
mean_estimate = np.copy(first_iteration)
dim = len(first_iteration)
# we do not start adaptation straight away
# just to give the algorithm a chance to look around
# many of these pre-adaptation proposals will probably be rejected, if the initial step size is too lareg
when_to_adapt = 100 * dim
theta_cur = np.copy(first_iteration)
cov_cur = np.copy(first_cov)
print "theta_cur =", theta_cur
log_target_cur = log_target_distribution(experiments, theta_cur, shapes,
scales, locs)
print "initial log_target_cur =", log_target_cur
# effectively step size, scales covariance matrix
loga = 0.
# what fraction of proposed samples are being accepted into the chain
acceptance = 0.
# what fraction of samples we WANT accepted into the chain
# loga updates itself to try to make this dream come true
target_acceptance = 0.25
# perform thinning to reduce autocorrelation (make saved iterations more closely represent independent samples from target distribution)
# also saves file space, win win
thinning = args.thinning
try:
total_iterations = args.iterations
except:
total_iterations = 200000
# after what fraction of total_iterations to print a little status message
status_when = 10000
saved_iterations = total_iterations / thinning + 1
pre_thin_burn = total_iterations / 4
# we discard the first quarter of iterations, as this gen
burn = saved_iterations / 4
# pre-allocate the space for MCMC iterations
# not a problem when we don't need to do LOADS of iterations
# but might become more of a hassle if we wanted to run it for ages along with loads of parameters
chain = np.zeros((saved_iterations, dim + 1))
chain[0, :] = np.copy(np.concatenate((first_iteration, [log_target_cur])))
# MCMC!
start = time.time()
t = 1
while t <= total_iterations:
theta_star = npr.multivariate_normal(theta_cur, np.exp(loga) * cov_cur)
log_target_star = log_target_distribution(experiments, theta_star,
shapes, scales, locs)
accept_prob = npr.rand()
if (np.log(accept_prob) < log_target_star - log_target_cur):
theta_cur = theta_star
log_target_cur = log_target_star
accepted = 1
else:
accepted = 0
acceptance = ((t - 1.) * acceptance + accepted) / t
if (t > when_to_adapt):
s = t - when_to_adapt
gamma_s = 1 / (s + 1)**0.6
temp_covariance_bit = np.array([theta_cur - mean_estimate])
cov_cur = (1 - gamma_s) * cov_cur + gamma_s * np.dot(
np.transpose(temp_covariance_bit), temp_covariance_bit)
mean_estimate = (1 - gamma_s) * mean_estimate + gamma_s * theta_cur
loga += gamma_s * (accepted - target_acceptance)
if t % thinning == 0:
chain[t / thinning, :] = np.concatenate(
(np.copy(theta_cur), [log_target_cur]))
if (t % status_when == 0):
print "{} / {}".format(t / status_when,
total_iterations / status_when)
time_taken_so_far = time.time() - start
estimated_time_left = time_taken_so_far / t * (total_iterations -
t)
print "Time taken: {} s = {} min".format(
np.round(time_taken_so_far, 1),
np.round(time_taken_so_far / 60, 2))
print "acceptance = {}".format(np.round(acceptance, 5))
print "Estimated time remaining: {} s = {} min".format(
np.round(estimated_time_left, 1),
np.round(estimated_time_left / 60, 2))
t += 1
print "**********"
print "final_iteration =", chain[-1, :]
with open(chain_file, 'a') as outfile:
np.savetxt(outfile, chain)
# save (alpha,mu) samples to be used as (Hill,pIC50) values in AP simulations
# these are direct 'top-level' samples, not samples from the posterior predictive distributions
indices = npr.randint(burn, saved_iterations, args.num_APs)
samples_file = dr.alpha_mu_downsampling(drug, channel)
AP_samples = chain[indices, :]
print "saving (alpha,mu) samples to", samples_file
with open(samples_file, 'w') as outfile:
outfile.write(
'# {} (alpha,mu) samples from hierarchical MCMC for {} + {}\n'.
format(args.num_APs, drug, channel))
np.savetxt(outfile, AP_samples[:, [0, 2]])
# this can be a quick visual check to see if the chain is mixing well
# it will plot one big tall figure with all parameter paths plotted
if args.plot_parameter_paths:
fig = plt.figure(figsize=(10, 4 * dim))
ax0 = fig.add_subplot(dim, 1, 1)
ax0.plot(chain[:, 0])
ax0.set_ylabel(r'$\alpha$')
plt.setp(ax0.get_xticklabels(), visible=False)
for i in range(1, dim):
ax = fig.add_subplot(dim, 1, i + 1, sharex=ax0)
ax.plot(chain[:t, i])
if i < dim - 1:
plt.setp(ax.get_xticklabels(), visible=False)
elif i == 1:
y_label = r'$\beta$'
elif i == 2:
y_label = r'$\mu$'
elif i == 3:
y_label = r'$s$'
elif (i % 2 == 0) and (i < dim - 1):
y_label = r'$pIC50_{' + str(i / 2 - 1) + '}$'
elif (i < dim - 1):
y_label = r'$Hill_{' + str(i / 2 - 1) + '}$'
else:
y_label = r'$\sigma$'
ax.set_xlabel('Iteration (thinned)')
ax.set_ylabel(y_label)
fig.tight_layout()
fig.savefig(figs_dir +
'{}_{}_parameter_paths.png'.format(drug, channel))
plt.close()
# plot all marginal posteriors separately, after discarding burn-in
# also a good visual check to see if it looks like they have converged
marginals_dir = figs_dir + 'marginals/png/'
if not os.path.exists(marginals_dir):
os.makedirs(marginals_dir)
for i in range(dim):
fig = plt.figure(figsize=(5, 4))
ax = fig.add_subplot(111)
ax.hist(chain[burn:, i],
bins=50,
normed=True,
color='blue',
edgecolor='blue')
ax.set_ylabel('Marginal probability density')
if i == 0:
x_label = r'$\alpha$'
filename = 'alpha'
elif i == 1:
x_label = r'$\beta$'
filename = 'beta'
elif i == 2:
x_label = r'$\mu$'
filename = 'mu'
elif i == 3:
x_label = r'$s$'
filename = 's'
elif (i % 2 == 0) and (i < dim - 1):
x_label = r'$Hill_{' + str(i / 2 - 1) + '}$'
filename = 'hill_{}'.format(i / 2 - 1)
elif (i < dim - 1):
x_label = r'$pIC50_{' + str(i / 2 - 1) + '}$'
filename = 'pic50_{}'.format(i / 2 - 1)
else:
x_label = r'$\sigma$'
filename = 'sigma'
ax.set_xlabel(x_label)
fig.tight_layout()
fig.savefig(marginals_dir +
'{}_{}_{}_marginal.png'.format(drug, channel, filename))
#fig.savefig(marginals_dir+'{}_{}_{}_marginal.pdf'.format(drug,channel,filename))
plt.close()
total_axes = (6, 4)
fig = plt.figure(figsize=(6, 7))
for i in range(5): # have to do sigma separately
if i == 0:
axloc = (0, 0)
elif i == 1:
axloc = (0, 2)
elif i == 2:
axloc = (2, 0)
elif i == 3:
axloc = (2, 2)
elif i == 4:
axloc = (4, 0)
ax = plt.subplot2grid(total_axes, axloc, colspan=2, rowspan=2)
ax.set_xlabel(labels[i])
ax.set_ylabel('Probability density')
ax.grid()
if (i < 4):
min_sample = np.min(chain[burn:, i])
max_sample = np.max(chain[burn:, i])
ax.hist(chain[burn:, i],
bins=50,
normed=True,
color='blue',
edgecolor='blue')
elif (i == 4):
min_sample = np.min(chain[burn:, -2])
max_sample = np.max(chain[burn:, -2])
ax.hist(chain[burn:, -2],
bins=50,
normed=True,
color='blue',
edgecolor='blue') # -1 would be log-target
ax.set_xlim(min_sample, max_sample)
pts_in_this_range = np.where((prior_xs[i] >= min_sample)
& (prior_xs[i] <= max_sample))
x_in_this_range = prior_xs[i][pts_in_this_range]
prior_in_this_range = priors[i][pts_in_this_range]
line = ax.plot(x_in_this_range,
prior_in_this_range,
lw=2,
color='red',
label='Prior distributions')
if (i == 0 or i == 3):
plt.xticks(rotation=90)
leg_ax = plt.subplot2grid(total_axes, (4, 2), colspan=2, rowspan=2)
leg_ax.axis('off')
hist = mpatches.Patch(color='blue', label='Normalised histograms')
leg_ax.legend(handles=line + [hist],
loc="center",
fontsize=12,
bbox_to_anchor=[0.38, 0.7])
fig.tight_layout()
fig.savefig(figs_dir + 'all_prior_distributions_and_marginals.png')
fig.savefig(figs_dir + 'all_prior_distributions_and_marginals.pdf')
plt.close()
print "Marginal plots saved in", marginals_dir
print "\n\n{} + {} complete!\n\n".format(drug, channel)
def sum_of_square_diffs(unscaled_params, doses, responses):
hill = unscaled_params[0]**2 # restricting Hill>0
pIC50 = unscaled_params[1]**2 - 1 # restricting pIC50>-1
IC50 = dr.pic50_to_ic50(pIC50)
test_responses = dr.dose_response_model(doses, hill, IC50)
return np.sum((test_responses - responses)**2)
def plot_mcmc_samples(drug_channel):
drug, channel = drug_channel
fig = plt.figure(figsize=(5, 8))
axes = {}
axes[1] = fig.add_subplot(211)
axes[2] = fig.add_subplot(212)
#drug = "Amiodarone"
#channel = "hERG"
# drug = "Lopinavir"
# channel = "Kir2.1"
num_models = 2
for model in xrange(1, num_models + 1):
dr.define_model(model)
chain_file = dr.define_chain_file(model, drug, channel, temperature)
num_expts, experiment_numbers, experiments = dr.load_crumb_data(
drug, channel)
figs_dir = dr.drug_channel_figs_dir(drug, channel)
concs = np.array([])
responses = np.array([])
for i in xrange(num_expts):
concs = np.concatenate((concs, experiments[i][:, 0]))
responses = np.concatenate((responses, experiments[i][:, 1]))
how_many_samples_to_plot = 1200
mcmc_samples = np.loadtxt(chain_file, usecols=range(dr.num_params))
saved_its = mcmc_samples.shape[0]
sample_indices = npr.randint(0, saved_its, how_many_samples_to_plot)
mcmc_samples = mcmc_samples[sample_indices]
conc_min = np.min(concs)
conc_max = np.max(concs)
fsize = 14
num_pts = 101
x_range = np.logspace(
int(np.log10(conc_min)) - 1,
int(np.log10(conc_max)) + 2, num_pts)
axes[model].set_xscale('log')
axes[model].grid()
axes[model].set_ylabel(r"% {} block".format(channel), fontsize=fsize)
axes[model].set_xlabel(r"{} concentration ($\mu$M)".format(drug),
fontsize=fsize)
axes[model].set_ylim(0, 100)
for i in xrange(how_many_samples_to_plot):
if model == 1:
pic50 = mcmc_samples[i, 0]
hill = 1
title = "$M_1$, fixed $Hill=1$, varying $pIC50$"
elif model == 2:
pic50, hill = mcmc_samples[i, :2]
title = "$M_2$, varying $pIC50$ and $Hill$"
axes[model].plot(x_range,
dr.dose_response_model(x_range, hill,
dr.pic50_to_ic50(pic50)),
color='black',
alpha=0.01)
axes[model].plot(concs,
responses,
'o',
color='orange',
ms=10,
label="Expt data")
axes[model].set_title(title, fontsize=fsize)
axes[model].legend(loc=2)
#axes[2].set_yticklabels([])
fig.tight_layout()
fig.savefig(all_figs_dir + '{}_{}_mcmc_samples.png'.format(drug, channel))
fig.savefig(figs_dir +
'{}_{}_mcmc_samples.pdf'.format(drug, channel, model))
plt.close()
return None
def run(drug_channel):
drug, channel = drug_channel
print "\n\n{} + {}\n\n".format(drug, channel)
num_expts, experiment_numbers, experiments = dr.load_crumb_data(
drug, channel)
if (0 < args.num_expts < num_expts):
num_expts = args.num_expts
drug, channel, output_dir, chain_dir, figs_dir, chain_file = dr.hierarchical_output_dirs_and_chain_file(
drug, channel, num_expts)
chain = np.loadtxt(chain_file)
end = chain.shape[0]
burn = end / 4
pic50_samples = np.zeros(args.num_hist_samples)
hill_samples = np.zeros(args.num_hist_samples)
rand_idx = npr.randint(burn, end, args.num_hist_samples)
for t in xrange(args.num_hist_samples):
alpha, beta, mu, s = chain[rand_idx[t], :4]
hill_samples[t] = st.fisk.rvs(c=beta, scale=alpha, loc=0)
pic50_samples[t] = st.logistic.rvs(mu, s)
num_pts = 40
fig = plt.figure(figsize=(11, 7))
ax1 = fig.add_subplot(231)
ax1.grid()
xmin = -4
xmax = 3
concs = np.logspace(xmin, xmax, num_pts)
ax1.set_xscale('log')
ax1.set_ylim(0, 100)
ax1.set_xlabel(r'{} concentration ($\mu$M)'.format(drug))
ax1.set_ylabel(r'% {} block'.format(channel))
ax1.set_title('A. Hierarchical predicted\nfuture experiments')
ax1.set_xlim(10**xmin, 10**xmax)
for expt in experiment_numbers:
ax1.scatter(experiments[expt][:, 0],
experiments[expt][:, 1],
label='Expt {}'.format(expt + 1),
color=colors[expt],
s=100,
zorder=10)
for i, conc in enumerate(args.concs):
ax1.axvline(conc,
color=colors[3 + i],
lw=2,
label=r"{} $\mu$M".format(conc),
alpha=0.8)
subset_idx = npr.randint(0, args.num_hist_samples, args.num_samples)
for i in xrange(
args.num_samples
): # only plot the first T of the H samples (should be fine because they're all randomly selected)
ax1.plot(concs,
dr.dose_response_model(concs, hill_samples[i],
dr.pic50_to_ic50(pic50_samples[i])),
color='black',
alpha=0.01)
lfs = 9
ax1.legend(loc=2, fontsize=lfs)
ax2 = fig.add_subplot(234)
ax2.set_xlim(0, 100)
ax2.set_xlabel(r'% {} block'.format(channel))
ax2.set_ylabel(r'Probability density')
ax2.grid()
for i, conc in enumerate(args.concs):
ax2.hist(dr.dose_response_model(conc, hill_samples,
dr.pic50_to_ic50(pic50_samples)),
bins=50,
normed=True,
color=colors[3 + i],
alpha=0.8,
lw=0,
label=r"{} $\mu$M {}".format(conc, drug))
ax2.set_title('D. Hierarchical predicted\nfuture experiments')
ax2.legend(loc="best", fontsize=lfs)
ax3 = fig.add_subplot(232, sharey=ax1, sharex=ax1)
ax3.grid()
ax3.set_xscale('log')
ax3.set_ylim(0, 100)
ax3.set_xlabel(r'{} concentration ($\mu$M)'.format(drug))
ax3.set_title('B. Hierarchical inferred\nunderlying effects')
ax3.set_xlim(10**xmin, 10**xmax)
for expt in experiment_numbers:
ax3.scatter(experiments[expt][:, 0],
experiments[expt][:, 1],
label='Expt {}'.format(expt + 1),
color=colors[expt],
s=100,
zorder=10)
alpha_indices = npr.randint(burn, end, args.num_samples)
alpha_samples = chain[alpha_indices, 0]
mu_samples = chain[alpha_indices, 2]
for i, conc in enumerate(args.concs):
ax3.axvline(conc,
color=colors[3 + i],
lw=2,
label=r"{} $\mu$M".format(conc),
alpha=0.8)
for i in xrange(args.num_samples):
ax3.plot(concs,
dr.dose_response_model(concs, alpha_samples[i],
dr.pic50_to_ic50(mu_samples[i])),
color='black',
alpha=0.01)
ax3.legend(loc=2, fontsize=lfs)
ax4 = fig.add_subplot(235, sharey=ax2, sharex=ax2)
ax4.set_xlim(0, 100)
ax4.set_xlabel(r'% {} block'.format(channel))
ax4.grid()
hist_indices = npr.randint(burn, end, args.num_hist_samples)
alphas = chain[hist_indices, 0]
mus = chain[hist_indices, 2]
for i, conc in enumerate(args.concs):
ax4.hist(dr.dose_response_model(conc, alphas, dr.pic50_to_ic50(mus)),
bins=50,
normed=True,
color=colors[3 + i],
alpha=0.8,
lw=0,
label=r"{} $\mu$M {}".format(conc, drug))
ax4.set_title('E. Hierarchical inferred\nunderlying effects')
plt.setp(ax3.get_yticklabels(), visible=False)
plt.setp(ax4.get_yticklabels(), visible=False)
# now plot non-hierarchical
num_params = 3
temperature = 1
if args.fix_hill:
model = 1
else:
model = 2
drug, channel, chain_file, figs_dir = dr.nonhierarchical_chain_file_and_figs_dir(
model, drug, channel, temperature)
chain = np.loadtxt(
chain_file,
usecols=range(num_params -
1)) # not interested in log-target values right now
end = chain.shape[0]
burn = end / 4
sample_indices = npr.randint(burn, end, args.num_samples)
samples = chain[sample_indices, :]
ax5 = fig.add_subplot(233, sharey=ax1, sharex=ax1)
ax5.grid()
plt.setp(ax5.get_yticklabels(), visible=False)
ax5.set_xscale('log')
ax5.set_ylim(0, 100)
ax5.set_xlim(10**xmin, 10**xmax)
ax5.set_xlabel(r'{} concentration ($\mu$M)'.format(drug))
ax5.set_title('C. Single-level inferred\neffects')
ax4.legend(loc="best", fontsize=lfs)
for expt in experiment_numbers:
if expt == 1:
ax5.scatter(experiments[expt][:, 0],
experiments[expt][:, 1],
color='orange',
s=100,
label='All expts',
zorder=10)
else:
ax5.scatter(experiments[expt][:, 0],
experiments[expt][:, 1],
color='orange',
s=100,
zorder=10)
for i, conc in enumerate(args.concs):
ax5.axvline(conc,
color=colors[3 + i],
alpha=0.8,
lw=2,
label=r"{} $\mu$M".format(conc))
for i in xrange(args.num_samples):
pic50, hill = samples[i, :]
ax5.plot(concs,
dr.dose_response_model(concs, hill, dr.pic50_to_ic50(pic50)),
color='black',
alpha=0.01)
ax5.legend(loc=2, fontsize=lfs)
sample_indices = npr.randint(burn, end, args.num_hist_samples)
samples = chain[sample_indices, :]
ax6 = fig.add_subplot(236, sharey=ax2, sharex=ax2)
ax6.set_xlim(0, 100)
ax6.set_xlabel(r'% {} block'.format(channel))
plt.setp(ax6.get_yticklabels(), visible=False)
ax6.grid()
for i, conc in enumerate(args.concs):
ax6.hist(dr.dose_response_model(conc, samples[:, 1],
dr.pic50_to_ic50(samples[:, 0])),
bins=50,
normed=True,
alpha=0.8,
color=colors[3 + i],
lw=0,
label=r"{} $\mu$M {}".format(conc, drug))
ax6.set_title('F. Single-level inferred\neffects')
ax6.legend(loc="best", fontsize=lfs)
plot_dir = dr.all_predictions_dir(drug, channel)
fig.tight_layout()
png_file = plot_dir + '{}_{}_all_predictions_corrected.png'.format(
drug, channel)
print png_file
fig.savefig(png_file)
pdf_file = plot_dir + '{}_{}_all_predictions_corrected.pdf'.format(
drug, channel)
print pdf_file
fig.savefig(
pdf_file
) # uncomment to save as pdf, or change extension to whatever you want
plt.close()
print "Figures saved in", plot_dir
def run(drug, channel):
print "\n\n{} + {}\n\n".format(drug, channel)
num_expts, experiment_numbers, experiments = dr.load_crumb_data(
drug, channel)
if (0 < (args.num_expts) < num_expts):
num_expts = args.num_expts
experiment_numbers = [x for x in experiment_numbers[:num_expts]]
experiments = [x for x in experiments[:num_expts]]
drug, channel, output_dir, chain_dir, figs_dir, chain_file = dr.hierarchical_output_dirs_and_chain_file(
drug, channel, num_expts)
chain = np.loadtxt(chain_file)
end, num_params = chain.shape
burn = end / 4
top_params = ['alpha', 'beta', 'mu', 's', 'sigma']
top_param_indices = [0, 1, 2, 3, num_params - 2]
mid_param_indices = [
i for i in range(num_params - 1) if i not in top_param_indices
]
num_expts = len(mid_param_indices) / 2
if num_expts <= 4: # qualitative and colourblind safe, apparently
colors = ['#a6cee3', '#1f78b4', '#b2df8a', '#33a02c']
colors = ['#d7191c', '#fdae61', '#2c7bb6']
else:
colors = [
'#a6cee3', '#1f78b4', '#b2df8a', '#33a02c', '#fb9a99', '#e31a1c',
'#fdbf6f', '#ff7f00', '#cab2d6', '#6a3d9a'
]
top_param_labels = [r'$\alpha$', r'$\beta$', r'$\mu$', r'$s$', r'$\sigma$']
num_curves = 50
indices = npr.randint(burn, end, num_curves)
samples = chain[indices, :]
all_fig = plt.figure(figsize=(4, 8))
curves = all_fig.add_subplot(311)
curves.set_xlabel(r'{} concentration ($\mu$M)'.format(drug))
curves.set_ylabel(r'% {} block'.format(channel))
curves.grid()
curves.set_xscale('log')
x_range = np.logspace(-4, 2, 201)
for j in xrange(num_curves):
for i in xrange(3):
response = dr.dose_response_model(
x_range, samples[j, 4 + 2 * i],
dr.pic50_to_ic50(samples[j, 4 + 2 * i + 1]))
curves.plot(x_range, response, color=colors[i], alpha=0.2)
for i, expt in enumerate(experiments):
curves.plot(expt[:, 0],
expt[:, 1],
'o',
color=colors[i],
zorder=10,
ms=10)
curves.set_xlim(10**-4, 10**2)
pic50s = all_fig.add_subplot(312)
pic50s.grid()
pic50s.set_ylabel('Probability density')
pic50s.set_xlabel(r'$pIC50_i$')
hills = all_fig.add_subplot(313)
hills.grid()
hills.set_ylabel('Probability density')
hills.set_xlabel(r'$Hill_i$')
alpha = 1. / (num_expts - 1)
for i, col in enumerate(mid_param_indices):
color = matplotlib.colors.ColorConverter().to_rgba(colors[i / 2],
alpha=alpha)
if i % 2 == 0:
label = r'$Hill_{}$'.format(i / 2 + 1)
file_label = 'Hill_{}'.format(i / 2 + 1)
hills.hist(chain[burn:, col],
normed=True,
bins=40,
color=color,
edgecolor='none',
label=r'$i = {}$'.format(i / 2 + 1))
else:
label = r'$pIC50_{}$'.format(i / 2 + 1)
file_label = 'pIC50_{}'.format(i / 2 + 1)
pic50s.hist(chain[burn:, col],
normed=True,
bins=40,
color=color,
edgecolor='none',
label=r'$i = {}$'.format(i / 2 + 1))
hills.legend(loc=1, fontsize=10)
all_fig.tight_layout()
all_fig.savefig(
figs_dir +
'{}_{}_hierarchical_curves_and_hists.png'.format(drug, channel))
#all_fig.savefig(figs_dir+'{}_{}_hierarchical_curves_and_hists.pdf'.format(drug,channel))
plt.show(block=True)
print "Figures saved in", figs_dir
print "\n\n{} + {} done\n\n".format(drug, channel)
def do_plots(drug_channel):
top_drug, top_channel = drug_channel
num_expts, experiment_numbers, experiments = dr.load_crumb_data(
top_drug, top_channel)
concs = np.array([])
responses = np.array([])
for i in xrange(num_expts):
concs = np.concatenate((concs, experiments[i][:, 0]))
responses = np.concatenate((responses, experiments[i][:, 1]))
xmin = 1000
xmax = -1000
for expt in experiments:
a = np.min(expt[:, 0])
b = np.max(expt[:, 0])
if a > 0 and a < xmin:
xmin = a
if b > xmax:
xmax = b
xmin = int(np.log10(xmin)) - 2
xmax = int(np.log10(xmax)) + 3
x = np.logspace(xmin, xmax, num_pts)
fig, (ax1, ax2) = plt.subplots(1,
2,
figsize=(9, 4),
sharey=True,
sharex=True)
ax1.set_xscale('log')
ax1.grid()
ax2.grid()
ax1.set_xlim(10**xmin, 10**xmax)
ax1.set_ylim(0, 100)
ax1.set_xlabel(r'{} concentration ($\mu$M)'.format(top_drug))
ax2.set_xlabel(r'{} concentration ($\mu$M)'.format(top_drug))
ax1.set_ylabel(r'% {} block'.format(top_channel))
model = 1
drug, channel, chain_file, images_dir = dr.nonhierarchical_chain_file_and_figs_dir(
model, top_drug, top_channel, temperature)
chain = np.loadtxt(chain_file)
best_idx = np.argmax(chain[:, -1])
best_pic50, best_sigma = chain[best_idx, [0, 1]]
saved_its, h = chain.shape
rand_idx = npr.randint(saved_its, size=num_curves)
pic50s = chain[rand_idx, 0]
ax1.set_title(r'Model 1: $pIC50 = {}$, fixed $Hill = 1$'.format(
np.round(best_pic50, 2)))
for i in xrange(num_curves):
ax1.plot(x,
dr.dose_response_model(x, 1., dr.pic50_to_ic50(pic50s[i])),
color='black',
alpha=0.02)
max_pd_curve = dr.dose_response_model(x, 1., dr.pic50_to_ic50(best_pic50))
ax1.plot(x, max_pd_curve, label='Max PD', lw=1.5, color='red')
ax1.plot(concs,
responses,
"o",
color='orange',
ms=10,
label='Data',
zorder=10)
anyArtist = plt.Line2D((0, 1), (0, 0), color='k')
handles, labels = ax1.get_legend_handles_labels()
if drug == "Quinine" and channel == "Nav1.5-late":
loc = 4
else:
loc = 2
ax1.legend(handles + [anyArtist], labels + ["Samples"], loc=loc)
model = 2
drug, channel, chain_file, images_dir = dr.nonhierarchical_chain_file_and_figs_dir(
model, top_drug, top_channel, temperature)
chain = np.loadtxt(chain_file)
best_idx = np.argmax(chain[:, -1])
best_pic50, best_hill, best_sigma = chain[best_idx, [0, 1, 2]]
ax2.set_title(r"Model 2: $pIC50={}$, Hill = {}".format(
np.round(best_pic50, 2), np.round(best_hill, 2)))
saved_its, h = chain.shape
rand_idx = npr.randint(saved_its, size=num_curves)
pic50s = chain[rand_idx, 0]
hills = chain[rand_idx, 1]
for i in xrange(num_curves):
ax2.plot(x,
dr.dose_response_model(x, hills[i],
dr.pic50_to_ic50(pic50s[i])),
color='black',
alpha=0.02)
max_pd_curve = dr.dose_response_model(x, best_hill,
dr.pic50_to_ic50(best_pic50))
ax2.plot(x, max_pd_curve, label='Max PD', lw=1.5, color='red')
ax2.plot(concs,
responses,
"o",
color='orange',
ms=10,
label='Data',
zorder=10)
handles, labels = ax2.get_legend_handles_labels()
ax2.legend(handles + [anyArtist], labels + ["Samples"], loc=loc)
fig.tight_layout()
#plt.show(block=True)
#sys.exit()
fig.savefig("{}_{}_nonh_both_models_mcmc_prediction_curves.png".format(
drug, channel))
plt.close()
return None
def run(drug_channel):
drug,channel = drug_channel
print "\n\n{} + {}\n\n".format(drug,channel)
num_expts, experiment_numbers, experiments = dr.load_crumb_data(drug,channel)
if (0 < args.num_expts < num_expts):
num_expts = args.num_expts
drug, channel, output_dir, chain_dir, figs_dir, chain_file = dr.hierarchical_output_dirs_and_chain_file(drug,channel,num_expts)
hill_cdf_file, pic50_cdf_file = dr.hierarchical_posterior_predictive_cdf_files(drug,channel,num_expts)
hill_cdf = np.loadtxt(hill_cdf_file)
pic50_cdf = np.loadtxt(pic50_cdf_file)
num_samples = 2000
unif_hill_samples = npr.rand(num_samples)
unif_pic50_samples = npr.rand(num_samples)
hill_samples = np.interp(unif_hill_samples, hill_cdf[:,1], hill_cdf[:,0])
pic50_samples = np.interp(unif_pic50_samples, pic50_cdf[:,1], pic50_cdf[:,0])
fig = plt.figure(figsize=(11,7))
ax1 = fig.add_subplot(231)
ax1.grid()
xmin = -4
xmax = 3
concs = np.logspace(xmin,xmax,101)
ax1.set_xscale('log')
ax1.set_ylim(0,100)
ax1.set_xlabel(r'{} concentration ($\mu$M)'.format(drug))
ax1.set_ylabel(r'% {} block'.format(channel))
ax1.set_title('A. Hierarchical predicted\nfuture experiments')
ax1.set_xlim(10**xmin,10**xmax)
for expt in experiment_numbers:
ax1.scatter(experiments[expt][:,0],experiments[expt][:,1],label='Expt {}'.format(expt+1),color=colors[expt],s=100,zorder=10)
for i, conc in enumerate(args.concs):
ax1.axvline(conc,color=colors[3+i],lw=2,label=r"{} $\mu$M".format(conc),alpha=0.8)
for i in xrange(num_samples):
ax1.plot(concs,dr.dose_response_model(concs,hill_samples[i],dr.pic50_to_ic50(pic50_samples[i])),color='black',alpha=0.01)
ax1.legend(loc=2,fontsize=10)
num_hist_samples = 100000
unif_hill_samples = npr.rand(num_hist_samples)
unif_pic50_samples = npr.rand(num_hist_samples)
hill_samples = np.interp(unif_hill_samples, hill_cdf[:,1], hill_cdf[:,0])
pic50_samples = np.interp(unif_pic50_samples, pic50_cdf[:,1], pic50_cdf[:,0])
ax2 = fig.add_subplot(234)
ax2.set_xlim(0,100)
ax2.set_xlabel(r'% {} block'.format(channel))
ax2.set_ylabel(r'Probability density')
ax2.grid()
for i, conc in enumerate(args.concs):
ax2.hist(dr.dose_response_model(conc,hill_samples,dr.pic50_to_ic50(pic50_samples)),bins=50,normed=True,color=colors[3+i],alpha=0.8,edgecolor='none',label=r"{} $\mu$M {}".format(conc,drug))
ax2.set_title('D. Hierarchical predicted\nfuture experiments')
ax2.legend(loc=2,fontsize=10)
ax3 = fig.add_subplot(232,sharey=ax1)
ax3.grid()
xmin = -4
xmax = 3
concs = np.logspace(xmin,xmax,101)
ax3.set_xscale('log')
ax3.set_ylim(0,100)
ax3.set_xlabel(r'{} concentration ($\mu$M)'.format(drug))
ax3.set_title('B. Hierarchical inferred\nunderlying effects')
ax3.set_xlim(10**xmin,10**xmax)
for expt in experiment_numbers:
ax3.scatter(experiments[expt][:,0],experiments[expt][:,1],label='Expt {}'.format(expt+1),color=colors[expt],s=100,zorder=10)
chain = np.loadtxt(chain_file)
end = chain.shape[0]
burn = end/4
num_samples = 1000
alpha_indices = npr.randint(burn,end,num_samples)
alpha_samples = chain[alpha_indices,0]
mu_samples = chain[alpha_indices,2]
for i, conc in enumerate(args.concs):
ax3.axvline(conc,color=colors[3+i],lw=2,label=r"{} $\mu$M".format(conc),alpha=0.8)
for i in xrange(num_samples):
ax3.plot(concs,dr.dose_response_model(concs,alpha_samples[i],dr.pic50_to_ic50(mu_samples[i])),color='black',alpha=0.01)
ax3.legend(loc=2,fontsize=10)
ax4 = fig.add_subplot(235,sharey=ax2)
ax4.set_xlim(0,100)
ax4.set_xlabel(r'% {} block'.format(channel))
ax4.grid()
num_hist_samples = 100000
hist_indices = npr.randint(burn,end,num_hist_samples)
alphas = chain[hist_indices,0]
mus = chain[hist_indices,2]
for i, conc in enumerate(args.concs):
ax4.hist(dr.dose_response_model(conc,alphas,dr.pic50_to_ic50(mus)),bins=50,normed=True,color=colors[3+i],alpha=0.8,edgecolor='none',label=r"{} $\mu$M {}".format(conc,drug))
ax4.set_title('E. Hierarchical inferred\nunderlying effects')
plt.setp(ax3.get_yticklabels(), visible=False)
plt.setp(ax4.get_yticklabels(), visible=False)
# now plot non-hierarchical
num_params = 3
drug,channel,chain_file,figs_dir = dr.nonhierarchical_chain_file_and_figs_dir(drug, channel, args.fix_hill)
chain = np.loadtxt(chain_file,usecols=range(num_params-1)) # not interested in log-target values right now
end = chain.shape[0]
burn = end/4
num_samples = 1000
sample_indices = npr.randint(burn,end,num_samples)
samples = chain[sample_indices,:]
ax5 = fig.add_subplot(233,sharey=ax1)
ax5.grid()
plt.setp(ax5.get_yticklabels(), visible=False)
xmin = -4
xmax = 4
concs = np.logspace(xmin,xmax,101)
ax5.set_xscale('log')
ax5.set_ylim(0,100)
ax5.set_xlim(10**xmin,10**xmax)
ax5.set_xlabel(r'{} concentration ($\mu$M)'.format(drug))
ax5.set_title('C. Single-level inferred\neffects')
ax5.legend(fontsize=10)
for expt in experiment_numbers:
if expt==1:
ax5.scatter(experiments[expt][:,0],experiments[expt][:,1],color='orange',s=100,label='All expts',zorder=10)
else:
ax5.scatter(experiments[expt][:,0],experiments[expt][:,1],color='orange',s=100,zorder=10)
for i, conc in enumerate(args.concs):
ax5.axvline(conc,color=colors[3+i],alpha=0.8,lw=2,label=r"{} $\mu$M".format(conc))
for i in xrange(num_samples):
ax5.plot(concs,dr.dose_response_model(concs,samples[i,0],dr.pic50_to_ic50(samples[i,1])),color='black',alpha=0.01)
ax5.legend(loc=2,fontsize=10)
num_hist_samples = 50000
sample_indices = npr.randint(burn,end,num_hist_samples)
samples = chain[sample_indices,:]
ax6 = fig.add_subplot(236,sharey=ax2)
ax6.set_xlim(0,100)
ax6.set_xlabel(r'% {} block'.format(channel))
plt.setp(ax6.get_yticklabels(), visible=False)
ax6.grid()
for i, conc in enumerate(args.concs):
ax6.hist(dr.dose_response_model(conc,samples[:,0],dr.pic50_to_ic50(samples[:,1])),bins=50,normed=True,alpha=0.8,color=colors[3+i],edgecolor='none',label=r"{} $\mu$M {}".format(conc,drug))
ax6.set_title('F. Single-level inferred\neffects')
ax2.legend(loc=2,fontsize=10)
plot_dir = dr.all_predictions_dir(drug,channel)
fig.tight_layout()
fig.savefig(plot_dir+'{}_{}_all_predictions.png'.format(drug,channel))
fig.savefig(plot_dir+'{}_{}_all_predictions.pdf'.format(drug,channel)) # uncomment to save as pdf, or change extension to whatever you want
plt.close()
print "Figures saved in", plot_dir
def plot_mcmc_samples(drug_channel):
drug, channel = drug_channel
fig = plt.figure(figsize=(5, 8))
axes = {}
axes[1] = fig.add_subplot(211)
axes[2] = fig.add_subplot(212)
#drug = "Amiodarone"
#channel = "hERG"
# drug = "Lopinavir"
# channel = "Kir2.1"
num_models = 2
for model in xrange(1, num_models+1):
dr.define_model(model)
chain_file = dr.define_chain_file(model, drug, channel, temperature)
num_expts, experiment_numbers, experiments = dr.load_crumb_data(drug, channel)
figs_dir = dr.drug_channel_figs_dir(drug, channel)
concs = np.array([])
responses = np.array([])
for i in xrange(num_expts):
concs = np.concatenate((concs, experiments[i][:, 0]))
responses = np.concatenate((responses, experiments[i][:, 1]))
how_many_samples_to_plot = 1200
mcmc_samples = np.loadtxt(chain_file, usecols=range(dr.num_params))
saved_its = mcmc_samples.shape[0]
sample_indices = npr.randint(0, saved_its, how_many_samples_to_plot)
mcmc_samples = mcmc_samples[sample_indices]
conc_min = np.min(concs)
conc_max = np.max(concs)
fsize = 14
num_pts = 101
x_range = np.logspace(int(np.log10(conc_min))-1, int(np.log10(conc_max))+2, num_pts)
axes[model].set_xscale('log')
axes[model].grid()
axes[model].set_ylabel(r"% {} block".format(channel), fontsize=fsize)
axes[model].set_xlabel(r"{} concentration ($\mu$M)".format(drug), fontsize=fsize)
axes[model].set_ylim(0,100)
for i in xrange(how_many_samples_to_plot):
if model == 1:
pic50 = mcmc_samples[i,0]
hill = 1
title = "$M_1$, fixed $Hill=1$, varying $pIC50$"
elif model == 2:
pic50, hill = mcmc_samples[i,:2]
title = "$M_2$, varying $pIC50$ and $Hill$"
axes[model].plot(x_range, dr.dose_response_model(x_range, hill, dr.pic50_to_ic50(pic50)),color='black',alpha=0.01)
axes[model].plot(concs, responses, 'o', color='orange', ms=10, label="Expt data")
axes[model].set_title(title, fontsize = fsize)
axes[model].legend(loc=2)
#axes[2].set_yticklabels([])
fig.tight_layout()
fig.savefig(all_figs_dir+'{}_{}_mcmc_samples.png'.format(drug, channel))
fig.savefig(figs_dir+'{}_{}_mcmc_samples.pdf'.format(drug,channel,model))
plt.close()
return None
def do_plot(drug_channel):
global concs, responses
fig = plt.figure(figsize=(5, 8))
axes = {}
axes[1] = fig.add_subplot(211)
axes[2] = fig.add_subplot(212)#, sharey=axes[1])
fsize = 14
for model in xrange(1, num_models+1):
dr.define_model(model)
drug, channel = drug_channel
num_expts, experiment_numbers, experiments = dr.load_crumb_data(drug, channel)
figs_dir = dr.drug_channel_figs_dir(drug, channel)
concs = np.array([])
responses = np.array([])
for i in xrange(num_expts):
concs = np.concatenate((concs, experiments[i][:, 0]))
responses = np.concatenate((responses, experiments[i][:, 1]))
if model == 1:
x0 = np.ones(2)
sigma0 = 0.1
elif model == 2:
x0 = np.copy([pic50, hill])
sigma0 = 0.01
#x0[0] = 6.9
opts = cma.CMAOptions()
es = cma.CMAEvolutionStrategy(x0, sigma0, opts)
while not es.stop():
X = es.ask()
f_vals = [sum_of_square_diffs(x, model) for x in X]
es.tell(X, f_vals)
es.disp()
res = es.result()
ss = res[1]
pic50, hill = res[0]
if model == 1:
hill = 1
conc_min = np.min(concs)
conc_max = np.max(concs)
num_pts = 501
x_range = np.logspace(int(np.log10(conc_min))-1, int(np.log10(conc_max))+2, num_pts)
predicted = dr.dose_response_model(x_range, hill, dr.pic50_to_ic50(pic50))
#fig = plt.figure(figsize=(5,4))
#ax = fig.add_subplot(111)
axes[model].grid()
axes[model].set_xscale('log')
axes[model].set_ylim(0,100)
axes[model].set_ylabel(r"% {} block".format(channel),fontsize=fsize)
axes[model].set_xlabel(r"{} concentration ($\mu$M)".format(drug),fontsize=fsize)
axes[model].plot(x_range, predicted, color='blue', lw=2, label="Best fit")
axes[model].plot(concs, responses, 'o', color='orange', ms=10, label="Expt data")
axes[model].legend(loc=2)
axes[model].set_title("$M_{}, pIC50 = {}, Hill = {}, SS = {}$".format(model, round(pic50,2), round(hill,2), round(ss,2)),fontsize=fsize)
#axes[2].set_yticklabels([])
fig.tight_layout()
#fig.savefig(figs_dir+"{}_{}_model_{}_best_fit.png".format(drug,channel,model))
fig.savefig(all_figs_dir+"{}_{}_best_fits.png".format(drug, channel))
fig.savefig(figs_dir+"{}_{}_best_fit.pdf".format(drug,channel))
plt.close()
def sum_of_square_diffs(_params, doses, responses):
pIC50, hill = _params
IC50 = dr.pic50_to_ic50(pIC50)
test_responses = dr.dose_response_model(doses, hill, IC50)
return np.sum((test_responses - responses)**2)
# could technically save 50% of the space for Model 1 by not bothering to save Hill=1 in every sample...
with open(txt_file, "w") as outfile:
outfile.write(
"# {} (pIC50,Hill) samples from single-level MCMC (model {}) for {} + {}\n"
.format(args.num_samples, args.model, drug, channel))
np.savetxt(outfile, chain)
fig, ax = plt.subplots(1, 1, figsize=(5, 4))
ax.grid()
ax.set_xlabel("{} concentration ($\mu$M)".format(drug))
ax.set_ylabel("% {} block".format(channel))
ax.set_xscale("log")
x = np.logspace(min_x, max_x, num_x_pts)
for t in xrange(args.num_samples):
pic50, hill = chain[t, :]
predicted_response_curve = dr.dose_response_model(
x, hill, dr.pic50_to_ic50(pic50))
ax.plot(x, predicted_response_curve, color='black', alpha=alpha)
if args.plot_data:
ax.plot(concs, responses, 'o', color='orange', ms=8, zorder=10)
fig.tight_layout()
fig.savefig(png_file)
print "\nSaved {}\n".format(samples_png)
if args.save_pdf:
fig.savefig(samples_pdf)
print "\nSaved {}\n".format(samples_pdf)
plt.close()
def run_single_level(drug_channel):
drug, channel = drug_channel
num_expts, experiment_numbers, experiments = dr.load_crumb_data(
drug, channel)
drug, channel, chain_file, images_dir = dr.nonhierarchical_chain_file_and_figs_dir(
drug, channel)
num_params = 3 # hill, pic50, mu
concs = np.array([])
responses = np.array([])
for i in xrange(num_expts):
concs = np.concatenate((concs, experiments[i][:, 0]))
responses = np.concatenate((responses, experiments[i][:, 1]))
print experiments
print concs
print responses
# uniform prior intervals
hill_prior = [0, 10]
pic50_prior = [-1, 20]
sigma_prior = [1e-3, 50]
prior_lowers = np.array([hill_prior[0], pic50_prior[0], sigma_prior[0]])
prior_uppers = np.array([hill_prior[1], pic50_prior[1], sigma_prior[1]])
# for reproducible results, otherwise select a new random seed
seed = 1
npr.seed(seed)
start = time.time()
x0 = np.array(
[1., 2.5]
) # not fitting sigma by CMA-ES, can maximise log-likelihood wrt sigma analytically
sigma0 = 0.1
opts = cma.CMAOptions()
opts['seed'] = seed
es = cma.CMAEvolutionStrategy(x0, sigma0, opts)
while not es.stop():
X = es.ask()
es.tell(X, [sum_of_square_diffs(x, concs, responses) for x in X])
es.disp()
res = es.result()
hill_cur = res[0][0]**2
pic50_cur = res[0][1]**2 - 1
sigma_cur = initial_sigma(len(responses), res[1])
proposal_scale = 0.01
theta_cur = np.array([hill_cur, pic50_cur, sigma_cur])
mean_estimate = np.copy(theta_cur)
cov_estimate = proposal_scale * np.diag(np.copy(np.abs(theta_cur)))
cmaes_ll = log_likelihood_single(responses, concs, theta_cur)
best_fit_fig = plt.figure(figsize=(5, 4))
best_fit_ax = best_fit_fig.add_subplot(111)
best_fit_ax.set_xscale('log')
best_fit_ax.grid()
plot_lower_lim = int(np.log10(np.min(concs))) - 1
plot_upper_lim = int(np.log10(np.max(concs))) + 2
best_fit_ax.set_xlim(10**plot_lower_lim, 10**plot_upper_lim)
best_fit_ax.set_ylim(0, 100)
num_pts = 1001
x_range = np.logspace(plot_lower_lim, plot_upper_lim, num_pts)
best_fit_curve = dr.dose_response_model(x_range, hill_cur,
dr.pic50_to_ic50(pic50_cur))
best_fit_ax.plot(x_range, best_fit_curve, label='Best fit', lw=2)
best_fit_ax.set_ylabel('% {} block'.format(channel))
best_fit_ax.set_xlabel(r'{} concentration ($\mu$M)'.format(drug))
best_fit_ax.set_title('Hill = {}, pIC50 = {}'.format(
np.round(hill_cur, 2), np.round(pic50_cur, 2)))
best_fit_ax.scatter(concs,
responses,
marker="o",
color='orange',
s=100,
label='Data',
zorder=10)
best_fit_ax.legend(loc=2)
best_fit_fig.tight_layout()
best_fit_fig.savefig(images_dir +
'{}_{}_CMA-ES_best_fit.png'.format(drug, channel))
best_fit_fig.savefig(images_dir +
'{}_{}_CMA-ES_best_fit.png'.format(drug, channel))
plt.close()
#sys.exit() # uncomment if you only want to plot the best fit
# let MCMC look around for a bit before adaptive covariance matrix
# same rule (100*dimension) as in hierarchical case
when_to_adapt = 100 * num_params
log_target_cur = log_likelihood_single(responses, concs, theta_cur)
print "initial log_target_cur =", log_target_cur
# effectively step size, scales covariance matrix
loga = 0.
# what fraction of proposed samples are being accepted into the chain
acceptance = 0.
# what fraction of samples we WANT accepted into the chain
# loga updates itself to try to make this dream come true
target_acceptance = 0.25
total_iterations = args.iterations
thinning = args.thinning
assert (total_iterations % thinning == 0)
# how often to print a little status message
status_when = total_iterations / 20
saved_iterations = total_iterations / thinning + 1
# also want to store log-target value at each iteration
chain = np.zeros((saved_iterations, num_params + 1))
chain[0, :] = np.concatenate((np.copy(theta_cur), [log_target_cur]))
print chain[0]
print "concs:", concs
print "responses:", responses
# MCMC!
t = 1
start = time.time()
while t <= total_iterations:
theta_star = npr.multivariate_normal(theta_cur,
np.exp(loga) * cov_estimate)
accepted = 0
if np.all(prior_lowers < theta_star) and np.all(
theta_star < prior_uppers):
log_target_star = log_likelihood_single(responses, concs,
theta_star)
accept_prob = npr.rand()
if (np.log(accept_prob) < log_target_star - log_target_cur):
theta_cur = theta_star
log_target_cur = log_target_star
accepted = 1
acceptance = ((t - 1.) * acceptance + accepted) / t
if (t > when_to_adapt):
s = t - when_to_adapt
gamma_s = 1 / (s + 1)**0.6
temp_covariance_bit = np.array([theta_cur - mean_estimate])
cov_estimate = (1 - gamma_s) * cov_estimate + gamma_s * np.dot(
np.transpose(temp_covariance_bit), temp_covariance_bit)
mean_estimate = (1 - gamma_s) * mean_estimate + gamma_s * theta_cur
loga += gamma_s * (accepted - target_acceptance)
if (t % thinning == 0):
chain[t / thinning, :] = np.concatenate(
(np.copy(theta_cur), [log_target_cur]))
if (t % status_when == 0):
print "{} / {}".format(t / status_when,
total_iterations / status_when)
time_taken_so_far = time.time() - start
estimated_time_left = time_taken_so_far / t * (total_iterations -
t)
print "Time taken: {} s = {} min".format(
np.round(time_taken_so_far, 1),
np.round(time_taken_so_far / 60, 2))
print "acceptance = {}".format(np.round(acceptance, 5))
print "Estimated time remaining: {} s = {} min".format(
np.round(estimated_time_left, 1),
np.round(estimated_time_left / 60, 2))
t += 1
print "\nTime taken to do {} MCMC iterations: {} s\n".format(
total_iterations,
time.time() - start)
print "Final iteration:", chain[-1, :], "\n"
with open(chain_file, 'w') as outfile:
outfile.write(
'# Nonhierarchical MCMC output for {} + {}: (Hill,pIC50,sigma,log-target)\n'
.format(drug, channel))
np.savetxt(outfile, chain)
try:
assert (len(chain[:, 0]) == saved_iterations)
except AssertionError:
print "len(chain[:,0])!=saved_iterations"
sys.exit()
burn_fraction = args.burn_in_fraction
burn = saved_iterations / burn_fraction
best_ll_index = np.argmax(chain[:, num_params])
best_ll_row = chain[best_ll_index, :]
print "Best log-likelihood:", "\n", best_ll_row
figs = []
axs = []
# plot all marginal posterior distributions
for i in range(num_params):
labels = ['Hill', 'pIC50', r'$\sigma$']
file_labels = ['Hill', 'pIC50', 'sigma']
figs.append(plt.figure())
axs.append([])
axs[i].append(figs[i].add_subplot(211))
axs[i][0].hist(chain[burn:, i], bins=40, normed=True)
axs[i][0].legend()
axs[i][0].set_title("MCMC marginal distributions")
axs[i].append(figs[i].add_subplot(212, sharex=axs[i][0]))
axs[i][1].plot(chain[burn:, i], range(burn, saved_iterations))
axs[i][1].invert_yaxis()
axs[i][1].set_xlabel(labels[i])
axs[i][1].set_ylabel('Saved MCMC iteration')
figs[i].tight_layout()
figs[i].savefig(
images_dir +
'{}_{}_{}_marginal.png'.format(drug, channel, file_labels[i]))
plt.close()
# plot log-target path
fig2 = plt.figure()
ax3 = fig2.add_subplot(111)
ax3.plot(range(saved_iterations), chain[:, -1])
ax3.set_xlabel('MCMC iteration')
ax3.set_ylabel('log-target')
fig2.tight_layout()
fig2.savefig(images_dir + 'log_target.png')
plt.close()
# plot scatterplot matrix of posterior(s)
labels = ['Hill', 'pIC50', r'$\sigma$']
colormin, colormax = 1e9, 0
norm = matplotlib.colors.Normalize(vmin=5, vmax=10)
hidden_labels = []
count = 0
# there's probably a better way to do this
# I plot all the histograms to normalize the colours, in an attempt to give a better comparison between the pairwise plots
while count < 2:
axes = {}
matrix_fig = plt.figure(figsize=(3 * num_params, 3 * num_params))
for i in range(num_params):
for j in range(i + 1):
ij = str(i) + str(j)
subplot_position = num_params * i + j + 1
if i == j:
axes[ij] = matrix_fig.add_subplot(num_params, num_params,
subplot_position)
axes[ij].hist(chain[burn:, i],
bins=50,
normed=True,
color='blue')
elif j == 0: # this column shares x-axis with top-left
axes[ij] = matrix_fig.add_subplot(num_params,
num_params,
subplot_position,
sharex=axes["00"])
counts, xedges, yedges, Image = axes[ij].hist2d(
chain[burn:, j],
chain[burn:, i],
cmap='hot_r',
bins=50,
norm=norm)
maxcounts = np.amax(counts)
if maxcounts > colormax:
colormax = maxcounts
mincounts = np.amin(counts)
if mincounts < colormin:
colormin = mincounts
else:
axes[ij] = matrix_fig.add_subplot(
num_params,
num_params,
subplot_position,
sharex=axes[str(j) + str(j)],
sharey=axes[str(i) + "0"])
counts, xedges, yedges, Image = axes[ij].hist2d(
chain[burn:, j],
chain[burn:, i],
cmap='hot_r',
bins=50,
norm=norm)
maxcounts = np.amax(counts)
if maxcounts > colormax:
colormax = maxcounts
mincounts = np.amin(counts)
if mincounts < colormin:
colormin = mincounts
if i != num_params - 1:
hidden_labels.append(axes[ij].get_xticklabels())
if j != 0:
hidden_labels.append(axes[ij].get_yticklabels())
if i == num_params - 1:
axes[str(i) + str(j)].set_xlabel(labels[j])
if j == 0:
axes[str(i) + str(j)].set_ylabel(labels[i])
plt.xticks(rotation=30)
norm = matplotlib.colors.Normalize(vmin=colormin, vmax=colormax)
count += 1
plt.setp(hidden_labels, visible=False)
matrix_fig.tight_layout()
matrix_fig.savefig(images_dir +
"{}_{}_scatterplot_matrix.png".format(drug, channel))
#matrix_fig.savefig(images_dir+"{}_{}_scatterplot_matrix.pdf".format(drug,channel))
plt.close()
print "\n\n{} + {} complete!\n\n".format(drug, channel)
