715 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			715 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
| import sys
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| 
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| try:
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|     from StringIO import StringIO
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| except ImportError:
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|     from io import StringIO
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| 
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| import numpy as np
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| from numpy.testing import (assert_, assert_array_equal, assert_allclose,
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|                            assert_equal)
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| from pytest import raises as assert_raises
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| 
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| from scipy.sparse import coo_matrix
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| from scipy.special import erf
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| from scipy.integrate._bvp import (modify_mesh, estimate_fun_jac,
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|                                   estimate_bc_jac, compute_jac_indices,
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|                                   construct_global_jac, solve_bvp)
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| 
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| import pytest
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| 
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| 
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| def exp_fun(x, y):
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|     return np.vstack((y[1], y[0]))
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| 
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| 
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| def exp_fun_jac(x, y):
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|     df_dy = np.empty((2, 2, x.shape[0]))
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|     df_dy[0, 0] = 0
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|     df_dy[0, 1] = 1
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|     df_dy[1, 0] = 1
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|     df_dy[1, 1] = 0
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|     return df_dy
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| 
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| 
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| def exp_bc(ya, yb):
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|     return np.hstack((ya[0] - 1, yb[0]))
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| 
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| 
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| def exp_bc_complex(ya, yb):
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|     return np.hstack((ya[0] - 1 - 1j, yb[0]))
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| 
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| 
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| def exp_bc_jac(ya, yb):
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|     dbc_dya = np.array([
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|         [1, 0],
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|         [0, 0]
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|     ])
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|     dbc_dyb = np.array([
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|         [0, 0],
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|         [1, 0]
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|     ])
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|     return dbc_dya, dbc_dyb
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| 
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| 
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| def exp_sol(x):
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|     return (np.exp(-x) - np.exp(x - 2)) / (1 - np.exp(-2))
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| 
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| 
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| def sl_fun(x, y, p):
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|     return np.vstack((y[1], -p[0]**2 * y[0]))
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| 
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| 
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| def sl_fun_jac(x, y, p):
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|     n, m = y.shape
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|     df_dy = np.empty((n, 2, m))
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|     df_dy[0, 0] = 0
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|     df_dy[0, 1] = 1
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|     df_dy[1, 0] = -p[0]**2
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|     df_dy[1, 1] = 0
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| 
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|     df_dp = np.empty((n, 1, m))
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|     df_dp[0, 0] = 0
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|     df_dp[1, 0] = -2 * p[0] * y[0]
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| 
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|     return df_dy, df_dp
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| 
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| 
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| def sl_bc(ya, yb, p):
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|     return np.hstack((ya[0], yb[0], ya[1] - p[0]))
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| 
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| 
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| def sl_bc_jac(ya, yb, p):
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|     dbc_dya = np.zeros((3, 2))
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|     dbc_dya[0, 0] = 1
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|     dbc_dya[2, 1] = 1
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| 
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|     dbc_dyb = np.zeros((3, 2))
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|     dbc_dyb[1, 0] = 1
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| 
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|     dbc_dp = np.zeros((3, 1))
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|     dbc_dp[2, 0] = -1
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| 
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|     return dbc_dya, dbc_dyb, dbc_dp
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| 
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| 
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| def sl_sol(x, p):
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|     return np.sin(p[0] * x)
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| 
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| 
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| def emden_fun(x, y):
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|     return np.vstack((y[1], -y[0]**5))
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| 
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| 
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| def emden_fun_jac(x, y):
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|     df_dy = np.empty((2, 2, x.shape[0]))
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|     df_dy[0, 0] = 0
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|     df_dy[0, 1] = 1
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|     df_dy[1, 0] = -5 * y[0]**4
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|     df_dy[1, 1] = 0
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|     return df_dy
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| 
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| 
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| def emden_bc(ya, yb):
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|     return np.array([ya[1], yb[0] - (3/4)**0.5])
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| 
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| 
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| def emden_bc_jac(ya, yb):
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|     dbc_dya = np.array([
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|         [0, 1],
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|         [0, 0]
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|     ])
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|     dbc_dyb = np.array([
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|         [0, 0],
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|         [1, 0]
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|     ])
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|     return dbc_dya, dbc_dyb
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| 
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| 
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| def emden_sol(x):
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|     return (1 + x**2/3)**-0.5
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| 
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| 
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| def undefined_fun(x, y):
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|     return np.zeros_like(y)
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| 
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| 
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| def undefined_bc(ya, yb):
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|     return np.array([ya[0], yb[0] - 1])
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| 
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| 
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| def big_fun(x, y):
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|     f = np.zeros_like(y)
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|     f[::2] = y[1::2]
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|     return f
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| 
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| 
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| def big_bc(ya, yb):
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|     return np.hstack((ya[::2], yb[::2] - 1))
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| 
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| 
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| def big_sol(x, n):
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|     y = np.ones((2 * n, x.size))
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|     y[::2] = x
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|     return x
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| 
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| 
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| def big_fun_with_parameters(x, y, p):
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|     """ Big version of sl_fun, with two parameters.
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| 
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|     The two differential equations represented by sl_fun are broadcast to the
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|     number of rows of y, rotating between the parameters p[0] and p[1].
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|     Here are the differential equations:
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| 
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|         dy[0]/dt = y[1]
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|         dy[1]/dt = -p[0]**2 * y[0]
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|         dy[2]/dt = y[3]
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|         dy[3]/dt = -p[1]**2 * y[2]
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|         dy[4]/dt = y[5]
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|         dy[5]/dt = -p[0]**2 * y[4]
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|         dy[6]/dt = y[7]
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|         dy[7]/dt = -p[1]**2 * y[6]
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|         .
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|         .
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|         .
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| 
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|     """
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|     f = np.zeros_like(y)
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|     f[::2] = y[1::2]
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|     f[1::4] = -p[0]**2 * y[::4]
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|     f[3::4] = -p[1]**2 * y[2::4]
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|     return f
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| 
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| 
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| def big_fun_with_parameters_jac(x, y, p):
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|     # big version of sl_fun_jac, with two parameters
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|     n, m = y.shape
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|     df_dy = np.zeros((n, n, m))
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|     df_dy[range(0, n, 2), range(1, n, 2)] = 1
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|     df_dy[range(1, n, 4), range(0, n, 4)] = -p[0]**2
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|     df_dy[range(3, n, 4), range(2, n, 4)] = -p[1]**2
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| 
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|     df_dp = np.zeros((n, 2, m))
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|     df_dp[range(1, n, 4), 0] = -2 * p[0] * y[range(0, n, 4)]
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|     df_dp[range(3, n, 4), 1] = -2 * p[1] * y[range(2, n, 4)]
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| 
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|     return df_dy, df_dp
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| 
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| 
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| def big_bc_with_parameters(ya, yb, p):
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|     # big version of sl_bc, with two parameters
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|     return np.hstack((ya[::2], yb[::2], ya[1] - p[0], ya[3] - p[1]))
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| 
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| 
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| def big_bc_with_parameters_jac(ya, yb, p):
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|     # big version of sl_bc_jac, with two parameters
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|     n = ya.shape[0]
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|     dbc_dya = np.zeros((n + 2, n))
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|     dbc_dyb = np.zeros((n + 2, n))
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| 
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|     dbc_dya[range(n // 2), range(0, n, 2)] = 1
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|     dbc_dyb[range(n // 2, n), range(0, n, 2)] = 1
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| 
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|     dbc_dp = np.zeros((n + 2, 2))
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|     dbc_dp[n, 0] = -1
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|     dbc_dya[n, 1] = 1
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|     dbc_dp[n + 1, 1] = -1
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|     dbc_dya[n + 1, 3] = 1
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| 
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|     return dbc_dya, dbc_dyb, dbc_dp
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| 
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| 
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| def big_sol_with_parameters(x, p):
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|     # big version of sl_sol, with two parameters
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|     return np.vstack((np.sin(p[0] * x), np.sin(p[1] * x)))
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| 
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| 
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| def shock_fun(x, y):
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|     eps = 1e-3
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|     return np.vstack((
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|         y[1],
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|         -(x * y[1] + eps * np.pi**2 * np.cos(np.pi * x) +
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|           np.pi * x * np.sin(np.pi * x)) / eps
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|     ))
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| 
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| 
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| def shock_bc(ya, yb):
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|     return np.array([ya[0] + 2, yb[0]])
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| 
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| 
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| def shock_sol(x):
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|     eps = 1e-3
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|     k = np.sqrt(2 * eps)
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|     return np.cos(np.pi * x) + erf(x / k) / erf(1 / k)
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| 
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| 
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| def nonlin_bc_fun(x, y):
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|     # laplace eq.
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|     return np.stack([y[1], np.zeros_like(x)])
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| 
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| 
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| def nonlin_bc_bc(ya, yb):
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|     phiA, phipA = ya
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|     phiC, phipC = yb
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| 
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|     kappa, ioA, ioC, V, f = 1.64, 0.01, 1.0e-4, 0.5, 38.9
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| 
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|     # Butler-Volmer Kinetics at Anode
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|     hA = 0.0-phiA-0.0
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|     iA = ioA * (np.exp(f*hA) - np.exp(-f*hA))
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|     res0 = iA + kappa * phipA
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| 
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|     # Butler-Volmer Kinetics at Cathode
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|     hC = V - phiC - 1.0
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|     iC = ioC * (np.exp(f*hC) - np.exp(-f*hC))
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|     res1 = iC - kappa*phipC
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| 
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|     return np.array([res0, res1])
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| 
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| 
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| def nonlin_bc_sol(x):
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|     return -0.13426436116763119 - 1.1308709 * x
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| 
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| 
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| def test_modify_mesh():
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|     x = np.array([0, 1, 3, 9], dtype=float)
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|     x_new = modify_mesh(x, np.array([0]), np.array([2]))
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|     assert_array_equal(x_new, np.array([0, 0.5, 1, 3, 5, 7, 9]))
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| 
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|     x = np.array([-6, -3, 0, 3, 6], dtype=float)
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|     x_new = modify_mesh(x, np.array([1], dtype=int), np.array([0, 2, 3]))
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|     assert_array_equal(x_new, [-6, -5, -4, -3, -1.5, 0, 1, 2, 3, 4, 5, 6])
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| 
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| 
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| def test_compute_fun_jac():
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|     x = np.linspace(0, 1, 5)
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|     y = np.empty((2, x.shape[0]))
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|     y[0] = 0.01
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|     y[1] = 0.02
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|     p = np.array([])
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|     df_dy, df_dp = estimate_fun_jac(lambda x, y, p: exp_fun(x, y), x, y, p)
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|     df_dy_an = exp_fun_jac(x, y)
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|     assert_allclose(df_dy, df_dy_an)
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|     assert_(df_dp is None)
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| 
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|     x = np.linspace(0, np.pi, 5)
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|     y = np.empty((2, x.shape[0]))
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|     y[0] = np.sin(x)
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|     y[1] = np.cos(x)
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|     p = np.array([1.0])
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|     df_dy, df_dp = estimate_fun_jac(sl_fun, x, y, p)
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|     df_dy_an, df_dp_an = sl_fun_jac(x, y, p)
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|     assert_allclose(df_dy, df_dy_an)
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|     assert_allclose(df_dp, df_dp_an)
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| 
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|     x = np.linspace(0, 1, 10)
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|     y = np.empty((2, x.shape[0]))
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|     y[0] = (3/4)**0.5
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|     y[1] = 1e-4
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|     p = np.array([])
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|     df_dy, df_dp = estimate_fun_jac(lambda x, y, p: emden_fun(x, y), x, y, p)
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|     df_dy_an = emden_fun_jac(x, y)
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|     assert_allclose(df_dy, df_dy_an)
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|     assert_(df_dp is None)
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| 
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| 
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| def test_compute_bc_jac():
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|     ya = np.array([-1.0, 2])
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|     yb = np.array([0.5, 3])
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|     p = np.array([])
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|     dbc_dya, dbc_dyb, dbc_dp = estimate_bc_jac(
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|         lambda ya, yb, p: exp_bc(ya, yb), ya, yb, p)
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|     dbc_dya_an, dbc_dyb_an = exp_bc_jac(ya, yb)
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|     assert_allclose(dbc_dya, dbc_dya_an)
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|     assert_allclose(dbc_dyb, dbc_dyb_an)
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|     assert_(dbc_dp is None)
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| 
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|     ya = np.array([0.0, 1])
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|     yb = np.array([0.0, -1])
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|     p = np.array([0.5])
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|     dbc_dya, dbc_dyb, dbc_dp = estimate_bc_jac(sl_bc, ya, yb, p)
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|     dbc_dya_an, dbc_dyb_an, dbc_dp_an = sl_bc_jac(ya, yb, p)
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|     assert_allclose(dbc_dya, dbc_dya_an)
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|     assert_allclose(dbc_dyb, dbc_dyb_an)
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|     assert_allclose(dbc_dp, dbc_dp_an)
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| 
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|     ya = np.array([0.5, 100])
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|     yb = np.array([-1000, 10.5])
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|     p = np.array([])
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|     dbc_dya, dbc_dyb, dbc_dp = estimate_bc_jac(
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|         lambda ya, yb, p: emden_bc(ya, yb), ya, yb, p)
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|     dbc_dya_an, dbc_dyb_an = emden_bc_jac(ya, yb)
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|     assert_allclose(dbc_dya, dbc_dya_an)
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|     assert_allclose(dbc_dyb, dbc_dyb_an)
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|     assert_(dbc_dp is None)
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| 
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| 
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| def test_compute_jac_indices():
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|     n = 2
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|     m = 4
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|     k = 2
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|     i, j = compute_jac_indices(n, m, k)
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|     s = coo_matrix((np.ones_like(i), (i, j))).toarray()
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|     s_true = np.array([
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|         [1, 1, 1, 1, 0, 0, 0, 0, 1, 1],
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|         [1, 1, 1, 1, 0, 0, 0, 0, 1, 1],
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|         [0, 0, 1, 1, 1, 1, 0, 0, 1, 1],
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|         [0, 0, 1, 1, 1, 1, 0, 0, 1, 1],
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|         [0, 0, 0, 0, 1, 1, 1, 1, 1, 1],
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|         [0, 0, 0, 0, 1, 1, 1, 1, 1, 1],
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|         [1, 1, 0, 0, 0, 0, 1, 1, 1, 1],
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|         [1, 1, 0, 0, 0, 0, 1, 1, 1, 1],
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|         [1, 1, 0, 0, 0, 0, 1, 1, 1, 1],
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|         [1, 1, 0, 0, 0, 0, 1, 1, 1, 1],
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|     ])
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|     assert_array_equal(s, s_true)
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| 
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| 
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| def test_compute_global_jac():
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|     n = 2
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|     m = 5
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|     k = 1
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|     i_jac, j_jac = compute_jac_indices(2, 5, 1)
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|     x = np.linspace(0, 1, 5)
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|     h = np.diff(x)
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|     y = np.vstack((np.sin(np.pi * x), np.pi * np.cos(np.pi * x)))
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|     p = np.array([3.0])
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| 
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|     f = sl_fun(x, y, p)
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| 
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|     x_middle = x[:-1] + 0.5 * h
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|     y_middle = 0.5 * (y[:, :-1] + y[:, 1:]) - h/8 * (f[:, 1:] - f[:, :-1])
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| 
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|     df_dy, df_dp = sl_fun_jac(x, y, p)
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|     df_dy_middle, df_dp_middle = sl_fun_jac(x_middle, y_middle, p)
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|     dbc_dya, dbc_dyb, dbc_dp = sl_bc_jac(y[:, 0], y[:, -1], p)
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| 
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|     J = construct_global_jac(n, m, k, i_jac, j_jac, h, df_dy, df_dy_middle,
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|                              df_dp, df_dp_middle, dbc_dya, dbc_dyb, dbc_dp)
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|     J = J.toarray()
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| 
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|     def J_block(h, p):
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|         return np.array([
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|             [h**2*p**2/12 - 1, -0.5*h, -h**2*p**2/12 + 1, -0.5*h],
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|             [0.5*h*p**2, h**2*p**2/12 - 1, 0.5*h*p**2, 1 - h**2*p**2/12]
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|         ])
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| 
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|     J_true = np.zeros((m * n + k, m * n + k))
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|     for i in range(m - 1):
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|         J_true[i * n: (i + 1) * n, i * n: (i + 2) * n] = J_block(h[i], p[0])
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| 
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|     J_true[:(m - 1) * n:2, -1] = p * h**2/6 * (y[0, :-1] - y[0, 1:])
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|     J_true[1:(m - 1) * n:2, -1] = p * (h * (y[0, :-1] + y[0, 1:]) +
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|                                        h**2/6 * (y[1, :-1] - y[1, 1:]))
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| 
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|     J_true[8, 0] = 1
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|     J_true[9, 8] = 1
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|     J_true[10, 1] = 1
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|     J_true[10, 10] = -1
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| 
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|     assert_allclose(J, J_true, rtol=1e-10)
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| 
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|     df_dy, df_dp = estimate_fun_jac(sl_fun, x, y, p)
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|     df_dy_middle, df_dp_middle = estimate_fun_jac(sl_fun, x_middle, y_middle, p)
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|     dbc_dya, dbc_dyb, dbc_dp = estimate_bc_jac(sl_bc, y[:, 0], y[:, -1], p)
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|     J = construct_global_jac(n, m, k, i_jac, j_jac, h, df_dy, df_dy_middle,
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|                              df_dp, df_dp_middle, dbc_dya, dbc_dyb, dbc_dp)
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|     J = J.toarray()
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|     assert_allclose(J, J_true, rtol=2e-8, atol=2e-8)
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| 
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| 
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| def test_parameter_validation():
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|     x = [0, 1, 0.5]
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|     y = np.zeros((2, 3))
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|     assert_raises(ValueError, solve_bvp, exp_fun, exp_bc, x, y)
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| 
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|     x = np.linspace(0, 1, 5)
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|     y = np.zeros((2, 4))
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|     assert_raises(ValueError, solve_bvp, exp_fun, exp_bc, x, y)
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| 
 | |
|     def fun(x, y, p):
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|         return exp_fun(x, y)
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|     def bc(ya, yb, p):
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|         return exp_bc(ya, yb)
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| 
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|     y = np.zeros((2, x.shape[0]))
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|     assert_raises(ValueError, solve_bvp, fun, bc, x, y, p=[1])
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| 
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|     def wrong_shape_fun(x, y):
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|         return np.zeros(3)
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| 
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|     assert_raises(ValueError, solve_bvp, wrong_shape_fun, bc, x, y)
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| 
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|     S = np.array([[0, 0]])
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|     assert_raises(ValueError, solve_bvp, exp_fun, exp_bc, x, y, S=S)
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| 
 | |
| 
 | |
| def test_no_params():
 | |
|     x = np.linspace(0, 1, 5)
 | |
|     x_test = np.linspace(0, 1, 100)
 | |
|     y = np.zeros((2, x.shape[0]))
 | |
|     for fun_jac in [None, exp_fun_jac]:
 | |
|         for bc_jac in [None, exp_bc_jac]:
 | |
|             sol = solve_bvp(exp_fun, exp_bc, x, y, fun_jac=fun_jac,
 | |
|                             bc_jac=bc_jac)
 | |
| 
 | |
|             assert_equal(sol.status, 0)
 | |
|             assert_(sol.success)
 | |
| 
 | |
|             assert_equal(sol.x.size, 5)
 | |
| 
 | |
|             sol_test = sol.sol(x_test)
 | |
| 
 | |
|             assert_allclose(sol_test[0], exp_sol(x_test), atol=1e-5)
 | |
| 
 | |
|             f_test = exp_fun(x_test, sol_test)
 | |
|             r = sol.sol(x_test, 1) - f_test
 | |
|             rel_res = r / (1 + np.abs(f_test))
 | |
|             norm_res = np.sum(rel_res**2, axis=0)**0.5
 | |
|             assert_(np.all(norm_res < 1e-3))
 | |
| 
 | |
|             assert_(np.all(sol.rms_residuals < 1e-3))
 | |
|             assert_allclose(sol.sol(sol.x), sol.y, rtol=1e-10, atol=1e-10)
 | |
|             assert_allclose(sol.sol(sol.x, 1), sol.yp, rtol=1e-10, atol=1e-10)
 | |
| 
 | |
| 
 | |
| def test_with_params():
 | |
|     x = np.linspace(0, np.pi, 5)
 | |
|     x_test = np.linspace(0, np.pi, 100)
 | |
|     y = np.ones((2, x.shape[0]))
 | |
| 
 | |
|     for fun_jac in [None, sl_fun_jac]:
 | |
|         for bc_jac in [None, sl_bc_jac]:
 | |
|             sol = solve_bvp(sl_fun, sl_bc, x, y, p=[0.5], fun_jac=fun_jac,
 | |
|                             bc_jac=bc_jac)
 | |
| 
 | |
|             assert_equal(sol.status, 0)
 | |
|             assert_(sol.success)
 | |
| 
 | |
|             assert_(sol.x.size < 10)
 | |
| 
 | |
|             assert_allclose(sol.p, [1], rtol=1e-4)
 | |
| 
 | |
|             sol_test = sol.sol(x_test)
 | |
| 
 | |
|             assert_allclose(sol_test[0], sl_sol(x_test, [1]),
 | |
|                             rtol=1e-4, atol=1e-4)
 | |
| 
 | |
|             f_test = sl_fun(x_test, sol_test, [1])
 | |
|             r = sol.sol(x_test, 1) - f_test
 | |
|             rel_res = r / (1 + np.abs(f_test))
 | |
|             norm_res = np.sum(rel_res ** 2, axis=0) ** 0.5
 | |
|             assert_(np.all(norm_res < 1e-3))
 | |
| 
 | |
|             assert_(np.all(sol.rms_residuals < 1e-3))
 | |
|             assert_allclose(sol.sol(sol.x), sol.y, rtol=1e-10, atol=1e-10)
 | |
|             assert_allclose(sol.sol(sol.x, 1), sol.yp, rtol=1e-10, atol=1e-10)
 | |
| 
 | |
| 
 | |
| def test_singular_term():
 | |
|     x = np.linspace(0, 1, 10)
 | |
|     x_test = np.linspace(0.05, 1, 100)
 | |
|     y = np.empty((2, 10))
 | |
|     y[0] = (3/4)**0.5
 | |
|     y[1] = 1e-4
 | |
|     S = np.array([[0, 0], [0, -2]])
 | |
| 
 | |
|     for fun_jac in [None, emden_fun_jac]:
 | |
|         for bc_jac in [None, emden_bc_jac]:
 | |
|             sol = solve_bvp(emden_fun, emden_bc, x, y, S=S, fun_jac=fun_jac,
 | |
|                             bc_jac=bc_jac)
 | |
| 
 | |
|             assert_equal(sol.status, 0)
 | |
|             assert_(sol.success)
 | |
| 
 | |
|             assert_equal(sol.x.size, 10)
 | |
| 
 | |
|             sol_test = sol.sol(x_test)
 | |
|             assert_allclose(sol_test[0], emden_sol(x_test), atol=1e-5)
 | |
| 
 | |
|             f_test = emden_fun(x_test, sol_test) + S.dot(sol_test) / x_test
 | |
|             r = sol.sol(x_test, 1) - f_test
 | |
|             rel_res = r / (1 + np.abs(f_test))
 | |
|             norm_res = np.sum(rel_res ** 2, axis=0) ** 0.5
 | |
| 
 | |
|             assert_(np.all(norm_res < 1e-3))
 | |
|             assert_allclose(sol.sol(sol.x), sol.y, rtol=1e-10, atol=1e-10)
 | |
|             assert_allclose(sol.sol(sol.x, 1), sol.yp, rtol=1e-10, atol=1e-10)
 | |
| 
 | |
| 
 | |
| def test_complex():
 | |
|     # The test is essentially the same as test_no_params, but boundary
 | |
|     # conditions are turned into complex.
 | |
|     x = np.linspace(0, 1, 5)
 | |
|     x_test = np.linspace(0, 1, 100)
 | |
|     y = np.zeros((2, x.shape[0]), dtype=complex)
 | |
|     for fun_jac in [None, exp_fun_jac]:
 | |
|         for bc_jac in [None, exp_bc_jac]:
 | |
|             sol = solve_bvp(exp_fun, exp_bc_complex, x, y, fun_jac=fun_jac,
 | |
|                             bc_jac=bc_jac)
 | |
| 
 | |
|             assert_equal(sol.status, 0)
 | |
|             assert_(sol.success)
 | |
| 
 | |
|             sol_test = sol.sol(x_test)
 | |
| 
 | |
|             assert_allclose(sol_test[0].real, exp_sol(x_test), atol=1e-5)
 | |
|             assert_allclose(sol_test[0].imag, exp_sol(x_test), atol=1e-5)
 | |
| 
 | |
|             f_test = exp_fun(x_test, sol_test)
 | |
|             r = sol.sol(x_test, 1) - f_test
 | |
|             rel_res = r / (1 + np.abs(f_test))
 | |
|             norm_res = np.sum(np.real(rel_res * np.conj(rel_res)),
 | |
|                               axis=0) ** 0.5
 | |
|             assert_(np.all(norm_res < 1e-3))
 | |
| 
 | |
|             assert_(np.all(sol.rms_residuals < 1e-3))
 | |
|             assert_allclose(sol.sol(sol.x), sol.y, rtol=1e-10, atol=1e-10)
 | |
|             assert_allclose(sol.sol(sol.x, 1), sol.yp, rtol=1e-10, atol=1e-10)
 | |
| 
 | |
| 
 | |
| def test_failures():
 | |
|     x = np.linspace(0, 1, 2)
 | |
|     y = np.zeros((2, x.size))
 | |
|     res = solve_bvp(exp_fun, exp_bc, x, y, tol=1e-5, max_nodes=5)
 | |
|     assert_equal(res.status, 1)
 | |
|     assert_(not res.success)
 | |
| 
 | |
|     x = np.linspace(0, 1, 5)
 | |
|     y = np.zeros((2, x.size))
 | |
|     res = solve_bvp(undefined_fun, undefined_bc, x, y)
 | |
|     assert_equal(res.status, 2)
 | |
|     assert_(not res.success)
 | |
| 
 | |
| 
 | |
| def test_big_problem():
 | |
|     n = 30
 | |
|     x = np.linspace(0, 1, 5)
 | |
|     y = np.zeros((2 * n, x.size))
 | |
|     sol = solve_bvp(big_fun, big_bc, x, y)
 | |
| 
 | |
|     assert_equal(sol.status, 0)
 | |
|     assert_(sol.success)
 | |
| 
 | |
|     sol_test = sol.sol(x)
 | |
| 
 | |
|     assert_allclose(sol_test[0], big_sol(x, n))
 | |
| 
 | |
|     f_test = big_fun(x, sol_test)
 | |
|     r = sol.sol(x, 1) - f_test
 | |
|     rel_res = r / (1 + np.abs(f_test))
 | |
|     norm_res = np.sum(np.real(rel_res * np.conj(rel_res)), axis=0) ** 0.5
 | |
|     assert_(np.all(norm_res < 1e-3))
 | |
| 
 | |
|     assert_(np.all(sol.rms_residuals < 1e-3))
 | |
|     assert_allclose(sol.sol(sol.x), sol.y, rtol=1e-10, atol=1e-10)
 | |
|     assert_allclose(sol.sol(sol.x, 1), sol.yp, rtol=1e-10, atol=1e-10)
 | |
| 
 | |
| 
 | |
| def test_big_problem_with_parameters():
 | |
|     n = 30
 | |
|     x = np.linspace(0, np.pi, 5)
 | |
|     x_test = np.linspace(0, np.pi, 100)
 | |
|     y = np.ones((2 * n, x.size))
 | |
| 
 | |
|     for fun_jac in [None, big_fun_with_parameters_jac]:
 | |
|         for bc_jac in [None, big_bc_with_parameters_jac]:
 | |
|             sol = solve_bvp(big_fun_with_parameters, big_bc_with_parameters, x,
 | |
|                             y, p=[0.5, 0.5], fun_jac=fun_jac, bc_jac=bc_jac)
 | |
| 
 | |
|             assert_equal(sol.status, 0)
 | |
|             assert_(sol.success)
 | |
| 
 | |
|             assert_allclose(sol.p, [1, 1], rtol=1e-4)
 | |
| 
 | |
|             sol_test = sol.sol(x_test)
 | |
| 
 | |
|             for isol in range(0, n, 4):
 | |
|                 assert_allclose(sol_test[isol],
 | |
|                                 big_sol_with_parameters(x_test, [1, 1])[0],
 | |
|                                 rtol=1e-4, atol=1e-4)
 | |
|                 assert_allclose(sol_test[isol + 2],
 | |
|                                 big_sol_with_parameters(x_test, [1, 1])[1],
 | |
|                                 rtol=1e-4, atol=1e-4)
 | |
| 
 | |
|             f_test = big_fun_with_parameters(x_test, sol_test, [1, 1])
 | |
|             r = sol.sol(x_test, 1) - f_test
 | |
|             rel_res = r / (1 + np.abs(f_test))
 | |
|             norm_res = np.sum(rel_res ** 2, axis=0) ** 0.5
 | |
|             assert_(np.all(norm_res < 1e-3))
 | |
| 
 | |
|             assert_(np.all(sol.rms_residuals < 1e-3))
 | |
|             assert_allclose(sol.sol(sol.x), sol.y, rtol=1e-10, atol=1e-10)
 | |
|             assert_allclose(sol.sol(sol.x, 1), sol.yp, rtol=1e-10, atol=1e-10)
 | |
| 
 | |
| 
 | |
| def test_shock_layer():
 | |
|     x = np.linspace(-1, 1, 5)
 | |
|     x_test = np.linspace(-1, 1, 100)
 | |
|     y = np.zeros((2, x.size))
 | |
|     sol = solve_bvp(shock_fun, shock_bc, x, y)
 | |
| 
 | |
|     assert_equal(sol.status, 0)
 | |
|     assert_(sol.success)
 | |
| 
 | |
|     assert_(sol.x.size < 110)
 | |
| 
 | |
|     sol_test = sol.sol(x_test)
 | |
|     assert_allclose(sol_test[0], shock_sol(x_test), rtol=1e-5, atol=1e-5)
 | |
| 
 | |
|     f_test = shock_fun(x_test, sol_test)
 | |
|     r = sol.sol(x_test, 1) - f_test
 | |
|     rel_res = r / (1 + np.abs(f_test))
 | |
|     norm_res = np.sum(rel_res ** 2, axis=0) ** 0.5
 | |
| 
 | |
|     assert_(np.all(norm_res < 1e-3))
 | |
|     assert_allclose(sol.sol(sol.x), sol.y, rtol=1e-10, atol=1e-10)
 | |
|     assert_allclose(sol.sol(sol.x, 1), sol.yp, rtol=1e-10, atol=1e-10)
 | |
| 
 | |
| 
 | |
| def test_nonlin_bc():
 | |
|     x = np.linspace(0, 0.1, 5)
 | |
|     x_test = x
 | |
|     y = np.zeros([2, x.size])
 | |
|     sol = solve_bvp(nonlin_bc_fun, nonlin_bc_bc, x, y)
 | |
| 
 | |
|     assert_equal(sol.status, 0)
 | |
|     assert_(sol.success)
 | |
| 
 | |
|     assert_(sol.x.size < 8)
 | |
| 
 | |
|     sol_test = sol.sol(x_test)
 | |
|     assert_allclose(sol_test[0], nonlin_bc_sol(x_test), rtol=1e-5, atol=1e-5)
 | |
| 
 | |
|     f_test = nonlin_bc_fun(x_test, sol_test)
 | |
|     r = sol.sol(x_test, 1) - f_test
 | |
|     rel_res = r / (1 + np.abs(f_test))
 | |
|     norm_res = np.sum(rel_res ** 2, axis=0) ** 0.5
 | |
| 
 | |
|     assert_(np.all(norm_res < 1e-3))
 | |
|     assert_allclose(sol.sol(sol.x), sol.y, rtol=1e-10, atol=1e-10)
 | |
|     assert_allclose(sol.sol(sol.x, 1), sol.yp, rtol=1e-10, atol=1e-10)
 | |
| 
 | |
| 
 | |
| @pytest.mark.thread_unsafe
 | |
| def test_verbose():
 | |
|     # Smoke test that checks the printing does something and does not crash
 | |
|     x = np.linspace(0, 1, 5)
 | |
|     y = np.zeros((2, x.shape[0]))
 | |
|     for verbose in [0, 1, 2]:
 | |
|         old_stdout = sys.stdout
 | |
|         sys.stdout = StringIO()
 | |
|         try:
 | |
|             sol = solve_bvp(exp_fun, exp_bc, x, y, verbose=verbose)
 | |
|             text = sys.stdout.getvalue()
 | |
|         finally:
 | |
|             sys.stdout = old_stdout
 | |
| 
 | |
|         assert_(sol.success)
 | |
|         if verbose == 0:
 | |
|             assert_(not text, text)
 | |
|         if verbose >= 1:
 | |
|             assert_("Solved in" in text, text)
 | |
|         if verbose >= 2:
 | |
|             assert_("Max residual" in text, text)
 |