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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)
gammasimp()
there, so have to get that case correctly too ! Never thought a gammasimp()
would alter limits from oo
to 0
but it does .Maybe if I find it too buggy and some more places where it the (n+1)**k - n**k
combo goes wrong , i'll raise this !
(n+1)**k -(n)**k
gives the correct answer . I am not sure why this may be happening but obviously it feels a bit strange if different arrangements of the same expression can lead to different answers! The gammasimp of that expression which returns 0 is (-n*n**k + n*(n + 1)**k + (n + 1)**k)
x = sin(x)
or x = log(x)
,x = e**x
. First one should return 0 in the Real domain and the other 2 should return an empty set . solveset()
method returns something like ConditionSet(x, Eq(x - sin(x), 0), Complexes)
, ConditionSet(x, Eq(x - exp(x), 0), Complexes)
which is not wrong but not what I would like and solvify
returns Not implemented for these !
I need to create a vector function in sympy with actual vectors, that can be transformed between coordinate systems.
I saw this https://stackoverflow.com/questions/46993819/how-to-create-a-vector-function-in-sympy which uses Matrix() as a workaround.
I need to transform my input and output vector from one coordinate system to another (and back). How are vector functions done in that case?
def B_el(r_vec):
r1 = r_vec.i
r2 = r_vec.j
u = sin(r1)+cos(r2)
v = -cos(r1)+sin(r2)
return Matrix([u, v, 0])
What would i need to change in order to return a vector, which can be transformed into a different (also resting) coordinate system, differing in axis rotations and a location shift?def B_el(r_vec): r1 = r_vec.i r2 = r_vec.j u = sin(r1)+cos(r2) v = -cos(r1)+sin(r2) return Matrix([u, v, 0])
Traceback (most recent call last):
File "C:/Users/Andreas Schuldei/PycharmProjects/lissajous-achse/hgü-kabel-detektion-symbolic.py", line 109, in <module>
result = solve(equations, (CM0, theta_i, theta_j, theta_k, i, a, B_earth))
File "C:\Users\Andreas Schuldei\PycharmProjects\lissajous-achse\venv\lib\site-packages\sympy\solvers\solvers.py", line 1096, in solve
solution = _solve_system(f, symbols, **flags)
File "C:\Users\Andreas Schuldei\PycharmProjects\lissajous-achse\venv\lib\site-packages\sympy\solvers\solvers.py", line 1730, in _solve_system
i, d = _invert(g, *symbols)
File "C:\Users\Andreas Schuldei\PycharmProjects\lissajous-achse\venv\lib\site-packages\sympy\solvers\solvers.py", line 3118, in _invert
rhs -= indep
File "C:\Users\Andreas Schuldei\PycharmProjects\lissajous-achse\venv\lib\site-packages\sympy\core\numbers.py", line 2194, in __sub__
return Rational.__sub__(self, other)
File "C:\Users\Andreas Schuldei\PycharmProjects\lissajous-achse\venv\lib\site-packages\sympy\core\decorators.py", line 89, in __sympifyit_wrapper
return func(a, b)
File "C:\Users\Andreas Schuldei\PycharmProjects\lissajous-achse\venv\lib\site-packages\sympy\core\numbers.py", line 1725, in __sub__
return Number.__sub__(self, other)
File "C:\Users\Andreas Schuldei\PycharmProjects\lissajous-achse\venv\lib\site-packages\sympy\core\decorators.py", line 89, in __sympifyit_wrapper
return func(a, b)
File "C:\Users\Andreas Schuldei\PycharmProjects\lissajous-achse\venv\lib\site-packages\sympy\core\numbers.py", line 733, in __sub__
return AtomicExpr.__sub__(self, other)
File "C:\Users\Andreas Schuldei\PycharmProjects\lissajous-achse\venv\lib\site-packages\sympy\core\decorators.py", line 251, in _func
return func(self, other)
File "C:\Users\Andreas Schuldei\PycharmProjects\lissajous-achse\venv\lib\site-packages\sympy\core\decorators.py", line 126, in binary_op_wrapper
return f(self)
File "C:\Users\Andreas Schuldei\PycharmProjects\lissajous-achse\venv\lib\site-packages\sympy\core\decorators.py", line 127, in binary_op_wrapper
return func(self, other)
File "C:\Users\Andreas Schuldei\PycharmProjects\lissajous-achse\venv\lib\site-packages\sympy\vector\basisdependent.py", line 352, in __rsub__
raise TypeError("Invalid argument types for subtraction")
TypeError: Invalid argument types for subtraction
How can I inspect the individual equations in the list equations to narrow this down? The equations are relatively long, and I have no clue how to find this.
Product(1, (n, 1, oo)).doit()
returns 1
and 1**oo
returns NaN
. Other integers work as expected . These expressions are equivalent right ??? or am I missing something !
as_leading_term()
method of core/expr.py (specifically on multivariable cases) . I would be glad if someone could clarify whether (1/x + y).as_leading_term(x)
and (1/x + y).as_leading_term(y)
, both should give back 1/x
as the ouput !!
:point_up: November 9, 2021 2:19 AM
yes, i believe that 1/x would be the lowest order term of both series expansions (when expanding around x it is the x^-1 term, when expanding around y it is the y^0 term): https://github.com/sympy/sympy/blob/00d6469eafdd4aac346a0b598184c15f2560dbe5/sympy/core/expr.py#L3411-L3445
it's a poorly named function. leading term to me means the part of the polynomial with the highest order, not the lowest order part of a series expansion.
Hello!
Is there any solution not to evaluate double equals ('==')?
Here is my simplified example:
from sympy.parsing.sympy_parser import parse_expr
expr = parse_expr('a == 1 + a', evaluate=False)
That returns False
. It seems to be flag evaluate=False
is ignored.
But, operation for ex. '<=' works 'properly' (for me) and returns:
>>> expr
a <= a + 1
>>> expr.func, expr.args
(<class 'sympy.core.relational.LessThan'>, (a, a + 1))
I need operation '==' has '<=' behavior during parsing with flag evaluate=False
and return:
>>> expr.func, expr.args
(<class 'sympy.core.relational.Equality'>, (a, a + 1))
Please, help solving my problem.
Dear all at Sympy, congrats on your work!
I am trying to use sympy Min/Max to evaluate a set of variables.
I have looked at: https://docs.sympy.org/latest/modules/functions/elementary.html#min
and
https://docs.sympy.org/latest/guides/assumptions.html
e.g.
a, b, c, d (we have no knowledge for them)
sympy.Max(a,b,c,d) = Max(a,b,c,d)
In case I have the hypothesis that a>c
can I somehow get
sympy.Min(a,b,c,d) = Min(a,b,d) ?
Any help appreciated,
best,
George
I seem to have found a wrong result when evaluating $\int dx/|x|$.
>>> x = symbols('x', real=True)
>>> integrate(1/abs(x), x)
Piecewise((-log(x), x <= 0), (nan, True))
The expected answer is $sgn(x) \log(|x|)$ except at x=0, where it is undefined (nan
). Sympy gives nan
for all x>0. Is this a known issue? I couldn't find one on Github. Just checking so I do not open a duplicate bug report.
integrate
giving wrong output for functions closely related to 1/x
. Closely related in the sense that they can be obtained after some modification or transformations on 1/x
but even I haven't been able to spot the above issue . Maybe you should report ?? @nchisholm