def __init__(self, settings, args, times_to_use):
par = Params()
self.times_to_use = times_to_use
self.starting_parameters = [2.26E-04, 0.0699, 3.45E-05, 0.05462, 0.0873, 8.92E-03, 5.150E-3, 0.03158, 0.1524]
# Create symbols for symbolic functions
p, y, v = CreateSymbols(settings)
# Choose starting parameters (from J Physiol paper)
para = [2.26E-04, 0.0699, 3.45E-05, 0.05462, 0.0873, 8.92E-03, 5.150E-3, 0.03158, 0.1524]
# Create symbols for symbolic functions
p, y, v = CreateSymbols(par)
# Define system equations and initial conditions
k1 = p[0] * se.exp(p[1] * v)
k2 = p[2] * se.exp(-p[3] * v)
k3 = p[4] * se.exp(p[5] * v)
k4 = p[6] * se.exp(-p[7] * v)
# Write in matrix form taking y = ([C], [O], [I])^T
A = se.Matrix([[-k1 - k3 - k4, k2 - k4, -k4], [k1, -k2 - k3, k4], [-k1, k3 - k1, -k2 - k4 - k1]])
B = se.Matrix([k4, 0, k1])
rhs = np.array(A * y + B)
self.funcs = GetSensitivityEquations(par, p, y, v, A, B, para, times_to_use, sine_wave=args.sine_wave)
def exp(expr):
"""Exponential"""
if type(expr) == GC:
return GC(
se.exp(expr.expr),
{s: d * se.exp(expr.expr)
for s, d in expr.gradients.items()})
return se.exp(expr)
def hermite(self, x=Symbol('x'), n=1):
expr1_hermite = Symbol('x')
expr2_hermite = (-1)**n
expr3_hermite = exp(0.5 * expr1_hermite**2)
expr4_hermite = diff(exp(-0.5 * expr1_hermite**2), expr1_hermite, n)
expr5_hermite = self.simplify(expr2_hermite * expr3_hermite *
expr4_hermite)
return expr5_hermite.subs([(expr1_hermite, x)])
def test_substitute_helpers(self):
backend = NumbaBackend()
a = se.Symbol("a")
b = se.Symbol("b")
y = se.Symbol("y")
HELPERS = [(a, se.exp(-12 * y))]
DERIVATIVES = [-b * a + y, y**2]
result = backend._substitute_helpers(DERIVATIVES, HELPERS)
self.assertListEqual(result, [-b * se.exp(-12 * y) + y, y**2])
def _radial(self, x, y, z, alphas, cs, rs=None, pre=None):
"""Generates the symbolic radial portion of a basis function.
Substitutes symbolic (_i) -> (_i - iA) for i in [x, y, z]."""
if pre is not None:
return sum((pre * self._expnt ** r * c * exp(-a * self._expnt)
for c, a, r in zip(cs, alphas, rs))
).subs({_x: _x - x, _y: _y - y, _z: _z - z})
return sum((c * exp(-a * self._expnt)
for c, a in zip(cs, alphas))
).subs({_x: _x - x, _y: _y - y, _z: _z - z})
def test_sens_limits():
par = Params()
p, y, v = CreateSymbols(par)
reversal_potential = par.Erev
para = np.array([
2.07, 7.17E1, 3.44E-2, 6.18E1, 4.18E2, 2.58E1, 4.75E1, 2.51E1, 3.33E1
])
para = para * 1E-3
# Define system equations and initial conditions
k1 = p[0] * se.exp(p[1] * v)
k2 = p[2] * se.exp(-p[3] * v)
k3 = p[4] * se.exp(p[5] * v)
k4 = p[6] * se.exp(-p[7] * v)
current_limit = (p[-1] * (par.holding_potential - reversal_potential) *
k1 / (k1 + k2) * k4 / (k3 + k4)).subs(
v, par.holding_potential)
print("{} Current limit computed as {}".format(
__file__,
current_limit.subs(p, para).evalf()))
sens_inf = [
float(se.diff(current_limit, p[j]).subs(p, para).evalf())
for j in range(0, par.n_params)
]
print("{} sens_inf calculated as {}".format(__file__, sens_inf))
k = se.symbols('k1, k2, k3, k4')
# Notation is consistent between the two papers
A = se.Matrix([[-k1 - k3 - k4, k2 - k4, -k4], [k1, -k2 - k3, k4],
[-k1, k3 - k1, -k2 - k4 - k1]])
B = se.Matrix([k4, 0, k1])
# Use results from HH equations
current_limit = (p[-1] * (par.holding_potential - reversal_potential) *
k1 / (k1 + k2) * k4 / (k3 + k4)).subs(
v, par.holding_potential)
funcs = GetSensitivityEquations(par, p, y, v, A, B, para, [0])
sens_inf = [
float(se.diff(current_limit, p[j]).subs(p, para).evalf())
for j in range(0, par.n_params)
]
sens = funcs.SimulateForwardModelSensitivities(para)[1]
# Check sens = sens_inf
error = np.abs(sens_inf - sens)
equal = np.all(error < 1e-10)
assert (equal)
return
def test_exp():
x = Symbol("x")
e1 = sympy.exp(sympy.Symbol("x"))
e2 = exp(x)
assert sympify(e1) == e2
assert e1 == e2._sympy_()
e1 = sympy.exp(sympy.Symbol("x")).diff(sympy.Symbol("x"))
e2 = exp(x).diff(x)
assert sympify(e1) == e2
assert e1 == e2._sympy_()
def test_exp():
x = Symbol("x")
e1 = sympy.exp(sympy.Symbol("x"))
e2 = exp(x)
assert sympify(e1) == e2
assert e1 == e2._sympy_()
e1 = sympy.exp(sympy.Symbol("x")).diff(sympy.Symbol("x"))
e2 = exp(x).diff(x)
assert sympify(e1) == e2
assert e1 == e2._sympy_()
def __init__(self, settings, args, times_to_use):
par = Params()
self.times_to_use = times_to_use
self.starting_parameters = [
2.26E-04, 0.0699, 3.45E-05, 0.05462, 0.0873, 8.92E-03, 5.150E-3,
0.03158, 0.1524
]
# Create symbols for symbolic functions
p, y, v = CreateSymbols(settings)
# Choose starting parameters (from J Physiol paper)
para = [
2.26E-04, 0.0699, 3.45E-05, 0.05462, 0.0873, 8.92E-03, 5.150E-3,
0.03158, 0.1524
]
# Define system equations and initial conditions
k1 = p[0] * se.exp(p[1] * v)
k2 = p[2] * se.exp(-p[3] * v)
k3 = p[4] * se.exp(p[5] * v)
k4 = p[6] * se.exp(-p[7] * v)
# Write in matrix form taking y = ([C], [O], [I])^T
A = se.Matrix([[-k1 - k3 - k4, k2 - k4, -k4], [k1, -k2 - k3, k4],
[-k1, k3 - k1, -k2 - k4 - k1]])
B = se.Matrix([k4, 0, k1])
rhs = np.array(A * y + B)
protocol = pd.read_csv(
os.path.join(
os.path.dirname(os.path.dirname(os.path.realpath(__file__))),
"protocols", "protocol-staircaseramp.csv"))
times = 10000 * protocol["time"].values
voltages = protocol["voltage"].values
staircase_protocol = scipy.interpolate.interp1d(times,
voltages,
kind="linear")
staircase_protocol_safe = lambda t: staircase_protocol(t) if t < times[
-1] else par.holding_potential
self.funcs = GetSensitivityEquations(par,
p,
y,
v,
A,
B,
para,
times_to_use,
voltage=staircase_protocol_safe)
def test_exp(self): f_1 = lambda time: [np.exp(time),0.5*np.exp(2*time)] f_2 = [symengine.exp(t),symengine.exp(2*t)/2] results = [] for function in (f_1,f_2): self.DDE.purge_past() self.DDE.past_from_function(function) self.DDE.step_on_discontinuities() times = np.arange( self.DDE.t, self.DDE.t+1000, 10 ) result = np.vstack( self.DDE.integrate(time) for time in times ) results.append(result) assert_allclose(results[0],results[1],atol=0.01,rtol=1e-5)
def test_scipy():
from scipy import integrate
import numpy as np
args = t, x = se.symbols('t, x')
lmb = se.Lambdify(args, [se.exp(-x * t) / t**5], as_scipy=True)
res = integrate.nquad(lmb, [[1, np.inf], [0, np.inf]])
assert abs(res[0] - 0.2) < 1e-7
def evaluate_expr(expr, xs, ys, zs, arr=None, alpha=None):
"""Evaluate symbolic expression on a numerical grid.
Args:
expr (symbolic): sympy or symengine expression
xs (np.ndarray): 1D-array of x values
ys (np.ndarray): 1D-array of y values
zs (np.ndarray): 1D-array of z values
arr (np.ndarray): additional 1D-array to multiply expression by
alpha (float): multiply expression by gaussian with exponent alpha
Note:
See :meth:`exatomic.algorithms.orbital_util.numerical_grid_from_field_params`
for grid construction details.
"""
subs = {_x: 'xs', _y: 'ys', _z: 'zs'}
# Multiply with an additional array (angular term)
if arr is not None:
return evaluate('arr * ({})'.format(str(expr.subs(subs))))
# Multiply by an exponential decay factor
if alpha is not None:
expr = str((expr * exp(-alpha * _r**2)).subs(subs))
return evaluate(expr)
# Just evaluate the expression numerically
return evaluate(str(expr.subs(subs)))
def evaluate_expr(expr, xs, ys, zs, arr=None, alpha=None):
"""Evaluate symbolic expression on a numerical grid.
Args:
expr (symbolic): sympy or symengine expression
xs (np.ndarray): 1D-array of x values
ys (np.ndarray): 1D-array of y values
zs (np.ndarray): 1D-array of z values
arr (np.ndarray): additional 1D-array to multiply expression by
alpha (float): multiply expression by gaussian with exponent alpha
Note:
See :meth:`exatomic.algorithms.orbital_util.numerical_grid_from_field_params`
for grid construction details.
"""
subs = {_x: 'xs', _y: 'ys', _z: 'zs'}
# Multiply with an additional array (angular term)
if arr is not None:
return evaluate('arr * ({})'.format(str(expr.subs(subs))))
# Multiply by an exponential decay factor
if alpha is not None:
expr = str((expr * exp(-alpha * _r ** 2)).subs(subs))
return evaluate(expr)
# Just evaluate the expression numerically
return evaluate(str(expr.subs(subs)))
def _get_array():
X, Y, Z = inp = array.array('d', [1, 2, 3])
args = x, y, z = se.symbols('x y z')
exprs = [x+y+z, se.sin(x)*se.log(y)*se.exp(z)]
ref = [X+Y+Z, math.sin(X)*math.log(Y)*math.exp(Z)]
def check(arr):
assert all([abs(x1-x2) < 1e-13 for x1, x2 in zip(ref, arr)])
return args, exprs, inp, check
def _get_array():
X, Y, Z = inp = array.array('d', [1, 2, 3])
args = x, y, z = se.symbols('x y z')
exprs = [x+y+z, se.sin(x)*se.log(y)*se.exp(z)]
ref = [X+Y+Z, math.sin(X)*math.log(Y)*math.exp(Z)]
def check(arr):
assert all([abs(x1-x2) < 1e-13 for x1, x2 in zip(ref, arr)])
return args, exprs, inp, check
def _lifted_gaussian(
t: sym.Symbol,
center: Union[sym.Symbol, sym.Expr, complex],
t_zero: Union[sym.Symbol, sym.Expr, complex],
sigma: Union[sym.Symbol, sym.Expr, complex],
) -> sym.Expr:
r"""Helper function that returns a lifted Gaussian symbolic equation.
For :math:`\sigma=` ``sigma`` the symbolic equation will be
.. math::
f(x) = \exp\left(-\frac12 \left(\frac{x - \mu}{\sigma}\right)^2 \right),
with the center :math:`\mu=` ``duration/2``.
Then, each output sample :math:`y` is modified according to:
.. math::
y \mapsto \frac{y-y^*}{1.0-y^*},
where :math:`y^*` is the value of the un-normalized Gaussian at the endpoints of the pulse.
This sets the endpoints to :math:`0` while preserving the amplitude at the center,
i.e. :math:`y` is set to :math:`1.0`.
Args:
t: Symbol object representing time.
center: Symbol or expression representing the middle point of the samples.
t_zero: The value of t at which the pulse is lowered to 0.
sigma: Symbol or expression representing Gaussian sigma.
Returns:
Symbolic equation.
"""
# Sympy automatically does expand.
# This causes expression inconsistency after qpy round-trip serializing through sympy.
# See issue for details: https://github.com/symengine/symengine.py/issues/409
t_shifted = (t - center).expand()
t_offset = (t_zero - center).expand()
gauss = sym.exp(-((t_shifted / sigma) ** 2) / 2)
offset = sym.exp(-((t_offset / sigma) ** 2) / 2)
return (gauss - offset) / (1 - offset)
def _radial(self, x, y, z, alphas, cs, rs=None, pre=None):
"""Generates the symbolic radial portion of a basis function.
Substitutes symbolic (_i) -> (_i - iA) for i in [x, y, z]."""
if pre is not None:
return sum((pre * self._expnt**r * c * exp(-a * self._expnt)
for c, a, r in zip(cs, alphas, rs))).subs({
_x: _x - x,
_y: _y - y,
_z: _z - z
})
return sum(
(c * exp(-a * self._expnt) for c, a in zip(cs, alphas))).subs({
_x:
_x - x,
_y:
_y - y,
_z:
_z - z
})
def test_symengine(arr, sig3):
"""Test symengine."""
try:
import symengine as sge
x, y, z = sge.var("x y z")
fn = sge.acos(x)/y + sge.exp(-z)
func = numbafy(fn, (x, y, z), compiler="vectorize", signatures=sig3)
result = func(arr, arr, arr)
check = np.arccos(arr)/arr + np.exp(-arr)
assert np.allclose(result, check) == True
except ImportError:
pass
def test_symengine(arr, sig3):
"""Test symengine."""
try:
import symengine as sge
x, y, z = sge.var("x y z")
fn = sge.acos(x) / y + sge.exp(-z)
func = numbafy(fn, (x, y, z), compiler="vectorize", signatures=sig3)
result = func(arr, arr, arr)
check = np.arccos(arr) / arr + np.exp(-arr)
assert np.allclose(result, check) == True
except ImportError:
pass
def _hermite_gaussians(lmax):
"""Symbolic hermite gaussians up to order lmax.
Args:
lmax (int): highest order angular momentum quantum number
"""
order = 2 * lmax + 1
hgs = OrderedDict()
der = exp(-_x**2)
for t in range(order):
if t: der = der.diff(_x)
hgs[t] = (-1)**t * der
return hgs
def projector(self):
mat = np.zeros((4, 4), dtype=object)
for n in range(1, self.N + 1):
Koef = self.Rho_Liste[n - 1] * si.exp(
-I * self.w_Liste[n - 1] * t[0])
Term11 = self.TensorProduct(
self.preMatrixPlus(self.K_Liste[n - 1]),
self.integralKernelPlus(n))
Term21 = self.TensorProduct(
self.preMatrixMinus(self.K_Liste[n - 1]),
self.integralKernelMinus(n))
mat += Koef * (Term11 + Term21)
return mat
def _hermite_gaussians(lmax):
"""Symbolic hermite gaussians up to order lmax.
Args:
lmax (int): highest order angular momentum quantum number
"""
order = 2 * lmax + 1
hgs = OrderedDict()
der = exp(-_x ** 2)
for t in range(order):
if t: der = der.diff(_x)
hgs[t] = (-1) ** t * der
return hgs
def LLF_sym(self, hazard, covariate_data):
# x = b, b1, b2, b2 = symengine.symbols('b b1 b2 b3')
x = symengine.symbols(f'x:{self.numSymbols}')
second = []
prodlist = []
for i in range(self.n):
sum1 = 1
sum2 = 1
TempTerm1 = 1
for j in range(self.numParameters, self.numSymbols):
TempTerm1 = TempTerm1 * symengine.exp(
covariate_data[j - self.numParameters][i] * x[j])
sum1 = 1 - ((1 -
(hazard(i + 1, x[:self.numParameters])))**(TempTerm1))
for k in range(i):
TempTerm2 = 1
for j in range(self.numParameters, self.numSymbols):
TempTerm2 = TempTerm2 * symengine.exp(
covariate_data[j - self.numParameters][k] * x[j])
sum2 = sum2 * (
(1 - (hazard(i + 1, x[:self.numParameters])))**(TempTerm2))
second.append(sum2)
prodlist.append(sum1 * sum2)
firstTerm = -sum(self.failures) #Verified
secondTerm = sum(self.failures) * symengine.log(
sum(self.failures) / sum(prodlist))
logTerm = [] #Verified
for i in range(self.n):
logTerm.append(self.failures[i] * symengine.log(prodlist[i]))
thirdTerm = sum(logTerm)
factTerm = [] #Verified
for i in range(self.n):
factTerm.append(symengine.log(math.factorial(self.failures[i])))
fourthTerm = sum(factTerm)
f = firstTerm + secondTerm + thirdTerm - fourthTerm
return f, x
def _HEXP_(node, S1, S2):
f = node.children[0].f_expression
errList1 = [node.f_expression] + \
[seng.expand(Si*node.f_expression) for Si in S1]
errList2 = [seng.expand(Si * node.f_expression) for Si in S2]
ferr = sum([seng.Abs(Si * pow(2, -53))
for Si in S1 + S2]) + node.f_expression
herr = sum([
seng.Abs(Si * Sj * seng.exp(ferr)) for Si in S1 + S2 for Sj in S1 + S2
])
return _solve_(node, errList1, errList2, herr)
def setUp(self):
interval = (-3, 2)
self.times = np.linspace(*interval, 10)
t = symengine.Symbol("t")
self.sin_spline = CubicHermiteSpline(n=1)
self.sin_spline.from_function(
[symengine.sin(t)],
times_of_interest=interval,
max_anchors=100,
)
self.sin_evaluation = self.sin_spline.get_state(self.times)
self.exp_spline = CubicHermiteSpline(n=1)
self.exp_spline.from_function(
[symengine.exp(t)],
times_of_interest=interval,
max_anchors=100,
)
self.exp_evaluation = self.exp_spline.get_state(self.times)
def solve_chi_saddlepoint(mu, Sigma):
"""Compute the saddlepoint approximation for the generalized chi square distribution given a mean and a covariance matrix. Currently has two different ways of solving:
1. If the mean is close to zero, the system can be solved symbolically."""
P = None
eigenvalues, eigenvectors = np.linalg.eig(Sigma)
if (eigenvectors == np.diag(eigenvalues)).all():
P = np.eye(len(mu))
else:
P = eigenvectors.T
Sigma_12 = np.linalg.cholesky(Sigma)
b = P @ Sigma_12 @ mu
x = sym.Symbol("x")
t = sym.Symbol("t")
# Cumulant function
K = 0
for i, l in enumerate(eigenvalues):
K += (t * b[i]**2 * l) / (1 - 2 * t * l) - 1 / 2 * sym.log(1 -
2 * l * t)
Kp = sym.diff(K, t).simplify()
Kpp = sym.diff(K, t, t).simplify()
roots = sym.lib.symengine_wrapper.solve(sym.Eq(Kp, x), t).args
if len(roots) > 1:
for expr in roots:
trial = Kpp.subs(t, expr).subs(x, np.dot(b, b))
if trial >= 0.0:
s_hat = expr
else:
s_hat = roots[0]
f = 1 / sym.sqrt(2 * sym.pi * Kpp.subs(
t, s_hat)) * sym.exp(K.subs(t, s_hat) - s_hat * x)
fp = sym.Lambdify(x, f.simplify())
c = integrate.quad(fp, 0, np.inf)[0]
return lambda x: 1 / c * fp(x)
def E(self, t=Symbol('t', positive=True)):
expr1_E = self.integrate(self.kappa(self.u), (self.u, 0, t))
return exp(expr1_E)
def _tau_m_h(self, voltage):
return 20.0 + 1000.0 / (exp(
(voltage + 71.5) / 14.2) + exp(-(voltage + 89.0) / 11.6))
def _m_inf_T(self, voltage):
return 1.0 / (1.0 + exp(-(voltage + 52.0) / 7.4))
def _h_inf_T(self, voltage):
return 1.0 / (1.0 + exp((voltage + 80.0) / 5.0))
def _tau_h_T(self, voltage):
return (85.0 + 1.0 / (exp(
(voltage + 48.0) / 4.0) + exp(-(voltage + 407.0) / 50.0))
) / 3.7371928
def n(self, x=Symbol('x'), Sigma=1):
return 1 / sqrt(2 * pi * Sigma) * exp(-0.5 * x**2 / Sigma)
def _m_inf_h(self, voltage):
return 1.0 / (1.0 + exp((voltage + 75.0) / 5.5))
def _get_firing_rate(self, voltage):
return self.params["Q_max"] / (
1.0 + exp(-self.params["C1"] *
(voltage - self.params["theta"]) / self.params["sigma"]))
def F(self, t=Symbol('t', positive=True)):
expr1_F = self.integrate(self.r(self.u), (self.u, 0, t))
return self.s0 * exp(expr1_F)
def _tau_h_T(self, voltage):
return (30.8 + (211.4 + exp((voltage + 115.2) / 5.0)) / (1.0 + exp(
(voltage + 86.0) / 3.2))) / 3.7371928
def _m_inf_T(self, voltage):
return 1.0 / (1.0 + exp(-(voltage + 59.0) / 6.2))
