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anutosh491 on GSoC_Pr4.2_Implementing_leading_term_and_series_methods_for_the_frac_function
anutosh491 on GSoC_Pr4.2_Implementing_leading_term_and_series_methods_for_the_frac_function
Implemented leading term and ns… (compare)
anutosh491 on GSoC_Pr4.2_Implementing_leading_term_and_series_methods_for_the_frac_function
made changes (compare)
anutosh491 on GSoC_Pr4.2_Implementing_leading_term_and_series_methods_for_the_frac_function
added tests for leading terms f… (compare)
anutosh491 on GSoC_Pr4.2_Implementing_leading_term_and_series_methods_for_the_frac_function
Changed the outputs being retur… (compare)
anutosh491 on GSoC_Pr4.2_Implementing_leading_term_and_series_methods_for_the_frac_function
Changed leading term being ret… (compare)
anutosh491 on GSoC_Pr4.2_Implementing_leading_term_and_series_methods_for_the_frac_function
Removed Redundant block from le… (compare)
anutosh491 on GSoC_Pr4.3_Implementing_some_series_method_for_uppergamma_lowergamma_expint_and_other_errors_functions
Implemented some series methods… (compare)
anutosh491 on GSoC_Pr4.2_Implementing_leading_term_and_series_methods_for_the_frac_function
Removed Order term (compare)
anutosh491 on GSoC_Pr4.2_Implementing_leading_term_and_series_methods_for_the_frac_function
added test cases for limits and… (compare)
anutosh491 on GSoC_Pr4.2_Implementing_leading_term_and_series_methods_for_the_frac_function
Implemented leading term and ns… (compare)
anutosh491 on GSoC_Pr4.1_Implementing_few_series_methods_for_bessel_functions
anutosh491 on GSoC_Pr4.1_Implementing_few_series_methods_for_bessel_functions
This commit does the following … Refactored mrv_leadterm in grun… Fixed errors arising for limits… and 3 more (compare)
anutosh491 on GSoC_Pr4.1_Implementing_few_series_methods_for_bessel_functions
fix(integrals): handle degenera… functions: Generalised Dirichle… author: update Megan Ly in .mai… and 23 more (compare)
anutosh491 on GSoC_Pr4.1_Implementing_few_series_methods_for_bessel_functions
Changed if condition for bessel… (compare)
anutosh491 on GSoC_Pr4.1_Implementing_few_series_methods_for_bessel_functions
Improved code quality (compare)
anutosh491 on GSoC_Pr4.1_Implementing_few_series_methods_for_bessel_functions
changed is function to equality… (compare)
anutosh491 on GSoC_Pr4.1_Implementing_few_series_methods_for_bessel_functions
fixed failing tests (compare)
anutosh491 on GSoC_Pr4.1_Implementing_few_series_methods_for_bessel_functions
Fixed code quality (compare)
anutosh491 on GSoC_Pr4.1_Implementing_few_series_methods_for_bessel_functions
Added case where number of term… (compare)
np.set_printoptions(precision=3)
PI = np.array([
[-11/12, 1/24, 0, 0, -1],
[ 17/24, -9/8, 1/24, 0 ,5],
[3/8, 9/8, -9/8, 1/24, -10],
[-5/24, -1/24, 9/8, -9/8, 10],
[1/24, 0, -1/24, 9/8, -5],
[0, 0, 0, -1/24, 1]
])
It seems that your system is over-determined. It has 6 equations in 5 variables. It can have solutions only if the determinant of the extended system is 0.
>>> P = Matrix([[ -0.917, 0.042, 0. , 0. , -1. ],
... [ 0.708, -1.125, 0.042, 0. , 5. ],
... [ 0.375, 1.125, -1.125, 0.042, -10. ],
... [ -0.208, -0.042, 1.125, -1.125, 10. ],
... [ 0.042, 0. , -0.042, 1.125, -5. ],
... [ 0. , 0. , 0. , -0.042, 1. ]])
>>> c = Matrix([-1. , 0. , 0. , -0.042, 1.083, -0.042])
>>> Pc = P.row_join(c)
>>> Pc.det()
0.000998125750125132
In this example, the determinant not 0 because of the inaccuracy of floating point numbers. Hence there is no solution.
A potential solution could be to define
rationalize = lambda x: [nsimplify(e) for e in x]
(this will turn numbers from a list into rationals). And then do
PI = Matrix(map(rationalize, [
[-11/12, 1/24, 0, 0, -1],
[ 17/24, -9/8, 1/24, 0 ,5],
[3/8, 9/8, -9/8, 1/24, -10],
[-5/24, -1/24, 9/8, -9/8, 10],
[1/24, 0, -1/24, 9/8, -5],
[0, 0, 0, -1/24, 1]
]))
and similarly for c
. I've just checked and this returns the right solutions
mrationalize = lambda x: [nsimplify(e) for e in [r for r in x]]
that I do not like much the fell.
I have a problem with calculating eigenvectors for a simple 3x3 matrix in sympy. Trying to execute
q = symbols("q", positive=True)
m = Matrix([[-2, exp(-q), 1], [exp(q), -2, 1], [1, 1, -2]])
#m.eigenvects(simplify=True)
m.eigenvals()
results in very complicated expressions for the eigenvalues, trying to get the eigenvectors fails with a NotImplementedError. I expect the latter to be due to the former. However, when trying to do the same thing in Mathematica, I get much simpler expressions for everything. Is there some option / flag that I can set to have sympy compute these eigenvalues and eigenvectors? Is there currently some form of limitation within sympy that prevents me from doing this?
simplify
simplify
flag, but it doesn't work
Add
does the smart substitution but Symbol
does not
x.subs(x - 1, y)
vs. (x + 1).subs(x - 1, y)