dict_title['random'] = 'Random-search'
dict_title['bayesian'] = 'Bayesian'
dict_title['grad_search'] = '1st order method'
plt.close('all')
fig, axarr = plt.subplots(1,
len(algorithms),
sharex=True,
sharey=True,
figsize=[10.67, 3])
objs_full = np.load("results/objs_grid_search100.npy", allow_pickle=True)
log_alphas_full = np.load("results/log_alphas_grid_search100.npy",
allow_pickle=True)
cmap = discrete_cmap(10, 'Reds')
c = np.linspace(1, 10, 10)
for i, algorithm in enumerate(algorithms):
objs = np.load("results/objs_%s.npy" % algorithm, allow_pickle=True)
log_alphas = np.load("results/log_alphas_%s.npy" % algorithm,
allow_pickle=True)
axarr[i].plot(log_alphas_full,
objs_full / objs_full[0],
color=current_palette[0],
zorder=1)
pcm = axarr[i].scatter(log_alphas,
objs / objs_full[0],
c=c,
cmap=cmap,
'adam': 'Reds'
}
fig, ax = plt.subplots(figsize=(8, 3))
ax.plot(alphas / alphas[0], objs, color=current_palette[0])
ax.plot(alphas / alphas[0],
objs,
'bo',
label='0-order method (grid-search)',
color=current_palette[1])
for optimizer_name in optimizer_names:
monitor = monitors[optimizer_name]
p_alphas_grad = np.array(monitor.alphas) / alpha_max
objs_grad = np.array(monitor.objs)
cmap = discrete_cmap(len(p_alphas_grad), dict_colors[optimizer_name])
ax.scatter(p_alphas_grad,
objs_grad,
label=optimizer_name,
marker='X',
color=cmap(np.linspace(0, 1, 10)),
zorder=10)
ax.set_xlabel(r"$\lambda / \lambda_{\max}$")
ax.set_ylabel(r"$ \sum_i^n \log \left ( 1 + e^{-y_i^{\rm{val}} X_i^{\rm{val}} "
r"\hat \beta^{(\lambda)} } \right ) $")
ax.set_xscale("log")
plt.tick_params(width=5)
plt.legend()
plt.tight_layout()
##############################################################################
# Plot results
# ------------
objs = reg.mse_path_.mean(axis=1)
p_alphas_grad = np.array(monitor_grad.alphas) / alpha_max
objs_grad = np.array(monitor_grad.objs)
print(f"Time for grid search: {t_sk:.2f} s")
print(f"Time for grad search (sparse-ho): {t_grad_search:.2f} s")
print(f'Minimum outer criterion value with grid search: {objs.min():.5f}')
print(f'Minimum outer criterion value with grad search: {objs_grad.min():.5f}')
current_palette = sns.color_palette("colorblind")
cmap = discrete_cmap(len(objs_grad), 'Greens')
fig, ax = plt.subplots(figsize=(5, 3))
ax.plot(alphas / alphas[0], objs, color=current_palette[0])
ax.plot(alphas / alphas[0],
objs,
'bo',
label='0-th order method (grid search)',
color=current_palette[1])
ax.scatter(p_alphas_grad,
objs_grad,
label='1-st order method',
marker='X',
color=cmap(np.linspace(0, 1, len(objs_grad))),
s=40,
zorder=40)
y,
alpha0=alpha0,
monitor=monitor)
t_grad_search += time.time()
monitor.alphas = np.array(monitor.alphas)
print("Time grid search %f" % t_grid_search)
print("Time grad-search %f" % t_grad_search)
print("Minimum grid search %0.3e" % results.min())
print("Minimum grad search %0.3e" % np.array(monitor.objs).min())
##############################################################################
# Plot results
# ------------
cmap = discrete_cmap(n_outer, 'Reds')
X, Y = np.meshgrid(alphas_l1 / alpha_max, alphas_l2 / alpha_max)
fig, ax = plt.subplots(1, 1)
cp = ax.contour(X, Y, results.T, levels=40)
ax.scatter(X,
Y,
s=10,
c="orange",
marker="o",
label="$0$th order (grid search)",
clip_on=False)
ax.scatter(monitor.alphas[:, 0] / alpha_max,
monitor.alphas[:, 1] / alpha_max,
s=40,
color=cmap(np.linspace(0, 1, n_outer)),
zorder=10,
objs_grad = np.array(monitor_grad.objs)
t_grad_search = time.time() - t0
print('sparse-ho finished')
print(f"Time to compute grad search: {t_grad_search:.2f} s")
p_alphas_grad = np.array(monitor_grad.alphas) / alpha_max
objs_grad = np.array(monitor_grad.objs)
current_palette = sns.color_palette("colorblind")
fig = plt.figure(figsize=(5, 3))
cmap = discrete_cmap(len(p_alphas_grad), "Greens")
plt.plot(alphas / alphas[0], objs, color=current_palette[0])
plt.plot(
alphas / alphas[0], objs, 'bo',
label='0-order method (grid-search)', color=current_palette[1])
plt.scatter(
p_alphas_grad, objs_grad, label='1-st order method',
marker='X', color=cmap(np.linspace(0, 1, len(objs_grad))), zorder=10)
plt.xlabel(r"$\lambda / \lambda_{\max}$")
plt.ylabel(
r"$ \sum_i^n \log \left ( 1 + e^{-y_i^{\rm{val}} X_i^{\rm{val}} "
r"\hat \beta^{(\lambda)} } \right ) $")
plt.xscale("log")
plt.tick_params(width=5)
levels = np.geomspace(min_grid, objs_full.max(), num=40)
levels = round_down(levels, 2)
plt.figure()
plt.contourf(X, Y, Z)
plt.plot()
for i, algorithm in enumerate(algorithms):
objs = np.load("results/%s_objs_%s_enet.npy" % (dataset, algorithm),
allow_pickle=True)
log_alphas = np.load("results/%s_log_alphas_%s_enet.npy" %
(dataset, algorithm),
allow_pickle=True)
assert objs.min() >= min_grid
cmap = discrete_cmap(len(objs), 'Reds')
c = np.linspace(1, len(objs), len(objs))
cs = axarr[i].contourf(X, Y, Z.T, levels=levels, cmap='viridis')
pcm = axarr[i].scatter(log_alphas[:, 0],
log_alphas[:, 1],
c=c,
marker='x',
cmap=cmap,
clip_on=False)
axarr[i].set_title(dict_title[algorithm])
axarr[i].set_xlabel("$\lambda_1 - \lambda_{\max}$")
print(objs.min())
cba = fig.colorbar(pcm, ax=axarr[3], ticks=[1, 5, 10, 15, 20, 25])
cba.set_label('Iterations')
grad_search(
algo, criterion, model, optimizer, X, y, alpha0=alpha0,
monitor=monitor)
t_grad_search += time.time()
monitor.alphas = np.array(monitor.alphas)
print("Time grid search %f" % t_grid_search)
print("Time grad-search %f" % t_grad_search)
print("Minimum grid search %0.3e" % results.min())
print("Minimum grad search %0.3e" % np.array(monitor.objs).min())
##############################################################################
# Plot results
# ------------
cmap = discrete_cmap(n_outer, 'Greens')
X, Y = np.meshgrid(alphas_l1 / alpha_max, alphas_l2 / alpha_max)
fig, ax = plt.subplots(1, 1)
cp = ax.contourf(X, Y, results.T)
ax.scatter(
X, Y, s=10, c="orange", marker="o", label="$0$th order (grid search)",
clip_on=False)
ax.scatter(
monitor.alphas[:, 0] / alpha_max, monitor.alphas[:, 1] / alpha_max,
s=40, color=cmap(np.linspace(0, 1, n_outer)), zorder=10,
marker="X", label="$1$st order")
ax.set_xlim(X.min(), X.max())
ax.set_xlabel("L1 regularization")
ax.set_ylabel("L2 regularization")
ax.set_ylim(Y.min(), Y.max())
ax.set_title("Elastic net held out prediction loss on test set")
