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2024-04-11 20:16:12 +0200 received badge  Nice Answer (source)
2024-03-27 19:08:37 +0200 answered a question Wrong answer for complex integral with maxima

Yes, the absolute value is omitted, as seen from integrating without limits, then differentiating the result: sage: ass

2024-03-27 18:50:27 +0200 answered a question sum of 2 squares

If we start with an integer $n>0$ with known (or computable) factorization $n=\prod_{p\in P} p^{r(p)}$, for some fini

2024-03-27 17:28:38 +0200 commented question Why does exponentiation result in a memory leak?

What about also indenting input ?!

2024-03-27 17:25:12 +0200 answered a question How to determine there is a k-path between two vertices

For the first question, on can use the $k$'th power of the adjacency matrix of the graph. (With or without the diagonal

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2024-03-23 04:04:39 +0200 answered a question Vertices of hyperbolic triangle with given angles

Here is the same code as posted on MO. However, here i is the place to say some words about the sage part of the impleme

2024-03-05 23:14:20 +0200 edited question Modular Forms

Modular Forms What is the most efficient way to determine the coefficients $$a_{1}, a_{2}, ..., a_{21}$$ such that $$\D

2024-02-26 17:05:55 +0200 answered a question Float-point precision in instantiation of point in Hyperbolic geometry module

Let us see what is exactly CC. For this, we compare: sage: CC(0.13816890584139213) 0.138168905841392 sage: CC Complex F

2024-02-17 22:07:57 +0200 commented answer Special value of Dedekind Zeta Functions

I hoped to get at least $\zeta_L(3)$ as a linear combination with rational coefficients of values of the trilogarithm co

2024-02-17 22:07:01 +0200 commented answer Special value of Dedekind Zeta Functions

I hoped to get at least $\zeta_L(3)$ as a linear combination with rational coefficients of values of the trilogarithm co

2024-02-17 22:05:39 +0200 answered a question Special value of Dedekind Zeta Functions

Let us get an explicit field $L$, i will ignore any restriction on $a,b$. a, b = 7, 3 # chosen so that we have a nic

2024-02-16 02:24:03 +0200 answered a question round function for matrices ?

Here is the same answer, some nuances are shown. The function / method numerical_approx(...) has the short hand n(...)an

2024-02-13 22:37:55 +0200 edited question Auslander-Reiten Quiver - knitting

Ausland-Reiten Quiver - knitting Given a quiver representation A3 = DiGraph({1 : {2 : ['a']}, 2 : {3 :

2024-02-13 14:58:26 +0200 received badge  Nice Answer (source)
2024-02-12 21:21:09 +0200 answered a question Meaning of the names of generators of ring of (quasi)modular forms

Let us take a look at the constructor called in order to build the instance QM2. First of all, it is mathematically a

2024-02-12 19:49:23 +0200 answered a question Converting between sized and unsized Permutations

Let us use names for the objects, i am working with particular examples. P = Permutations(7) Q = Permutations(9) s =

2024-02-05 18:54:00 +0200 commented question Is there a bug in heaviside function?

Make sure that x is a variable when defining f. In my case, the following worked: sage: var('x'); sage: f = heaviside(x

2024-02-05 18:38:05 +0200 commented question How to take inverse of matrix with complex entries

.... continued: But Jordan form will require that the eigenvalues of the matrix can be represented within Sage, r

2024-02-05 18:33:19 +0200 commented question How to take inverse of matrix with complex entries

Which is the field / domain of definition for the entries of the two matrices K_1 and K_2 - that i will denote by A and

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2024-01-26 03:44:06 +0200 answered a question plotting origin location

You may want (next time) to rearrange the code, so that it gets readable. Also, respecting PEP8 and PEP40 may let the re

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2024-01-26 02:59:00 +0200 answered a question Draw a list of continuously colored points

Here is a way, i tried in hurry: N = 1000 R = range(N) def myrgbcolor(k): # you may try also some other functions

2024-01-24 18:17:23 +0200 received badge  Good Answer (source)
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2024-01-23 14:39:21 +0200 commented question How can I construct matrices over the octonions?

Which operations are needed for these matrices over the octonions? Just make an own class if the wanted mathematical app

2024-01-22 20:58:49 +0200 commented question Interacting not only for the value but before for the dimensions

Please give us the reason why this question is relevant to sage. (The code does in sage specifically only the story wit

2024-01-22 20:58:28 +0200 commented question Interacting not only for the value but before for the dimensions

Please give us the reason why this question is relevant to sage. (The code does in sage specifically only the story wit

2024-01-22 20:43:58 +0200 answered a question if we know that the vectors are dependant i need to determine the relation between v9 = vector([0, 0, -2, 0, 4, -2, 12, 8, -18]) and the following vectors

Please always mention the own effort to solve the problem. Well, in this case it is simpler to deliver the solution then

2024-01-22 19:13:57 +0200 answered a question Question in general orthogonal group

As reference i am using https://doc.sagemath.org/html/en/reference/groups/sage/groups/matrix_gps/orthogonal_gap.html. T

2024-01-01 15:32:24 +0200 answered a question Power Series over q

I will use $\tau$ instead of $z$, and assume that we have the nome-convention: $$ q = q(\tau)=e^{2\pi i\; \tau}\ . $$ Th

2024-01-01 06:45:46 +0200 commented question 2x2 Rubik's cube

See also https://doc.sagemath.org/html/en/reference/spkg/rubiks.html

2024-01-01 06:29:03 +0200 answered a question listing desired polynomials of given degree

Here is a first brute force solution. I will use q instead of b. Let $F=\Bbb F_q=$GF(q) be the field with $q$ elements.

2023-12-07 02:57:31 +0200 commented question Multivariate polynomials via FLINT

No trick could force the present code (in my hands) to use FLINT. From https://fredrikj.net/math/lyon2023flint.pdf is se

2023-12-07 02:37:33 +0200 commented question Multivariate polynomials via FLINT

Let us take a look at the doc string... sage: ?PolynomialRing After some lines, we get the block: * "implementati

2023-12-07 02:26:33 +0200 commented question Expression.simplify() takes no "algorithm" keyword

Version 10.1 does the job. To see if a method accepts some arguments, ask for its doc string. For instance, with the ab

2023-12-07 02:19:59 +0200 answered a question Incidence graphs of generalised quadrangle and hexagon

After the comment of FrédéricC i took at the generalized hexagon graphs that sage may construct for some small values of

2023-12-07 01:12:51 +0200 edited question Incidence graphs of generalised quadrangle and hexagon

Incidence graphs of generalised quadrangle and hexagon For an introduction to generalised polygons, see https://cage.uge

2023-12-03 19:08:14 +0200 commented question Incidence graphs of generalised quadrangle and hexagon

Please give some references to the mathematical definition of the involved objects. Or some sample minimal code initiali

2023-12-03 17:44:05 +0200 edited answer Finding projective orders over residual class rings of form Z / (p)^{n} Z

I will use $p$ for $13$ for short. Let $F$ be the field with $p=13$ elements, $F=\Bbb Z/13=\Bbb F_{13}$. Let $R=\Bbb Z/1

2023-12-03 17:02:01 +0200 answered a question Finding projective orders over residual class rings of form Z / (p)^{n} Z

I will use $p$ for $13$ for short. Let $F$ be the field with $p=13$ elements, $F=\Bbb Z/13=\Bbb F_{13}$. Let $R=\Bbb Z/1

2023-11-21 19:34:59 +0200 received badge  Nice Answer (source)
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2023-11-21 05:08:04 +0200 answered a question Is there a bug with the "parts" input in VectorPartitions?

I took a look to the code of the VectorPartitions and there was a line that i could not understand immediately... @stat

2023-11-21 01:21:12 +0200 answered a question "points must be on same curve" ( ate_pairing, BLS12-381)

The following works for me: # parameters for BLS12-381 z = -0xd201000000010000 # this is z = -15132376222941642752

2023-11-21 00:08:11 +0200 commented question "points must be on same curve" ( ate_pairing, BLS12-381)

Posting as anonymous has some drawbacks... it may be a good idea to get please a user name... The question starts by int