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Questions tagged [magma-cas]

Magma is a computer algebra system distributed by the University of Sydney, and designed for solving problems in algebra, number theory, geometry and combinatorics.

Magma is a computer algebra system distributed by the Computational Algebra Group at the University of Sydney. It is designed for solving problems in algebra, number theory, geometry and combinatorics. It is named after the algebraic structure magma.

187 questions
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Limit of time to get an output on MAGMA

I would to ask you if there is a way to put a MAGMA command that stop a function in a script if the occurring time is greater than a certain prefixed time $T\geq 0$ (for example $T=15 $ minutes ). After this stop, I would that the script goes on to…
Federico Fallucca
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Magma : Load file using variable file name

I want to load an external Magma file within another Magma file. (Both files are saved in the same directory.) I want to be able to quickly change which external file is being loaded, ideally at the beginning of the file making the load call, so…
ev.gal
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MAGMA: coercing matrix group to permutation group

I'm just starting out with using the MAGMA computer algebra system, and can't figure out how to tell MAGMA to consider $GL(3,2)$ as a permutation group, using the natural action on $(\mathbb F_2)^3$. Some background: I would like to compute double…
Josh Hunt
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MAGMA miscalculation of NilpotencyClass

I'm copying this question from over at SO, since there is no tag about the MAGMA cas over there, as I only just figured out. Hope someone can answer over here. Not asking for migration because I've been waiting for an answer for a month and over…
MickG
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Magma error: User error: Imported environment value 'z' cannot be used as a local

Can anyone figure out how to fix this error? I want to define z beginning as 1 and update z to 2z everytime. Basically I was z = 1, 2, 4, 8, 16, .... z := 1; Successive := procedure(x1,y1,d); procedure> F :=…
Adam Staples
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"No permutation group context" when using printf in MAGMA

I tried to write a very simple code in Magma to print a matrix in a way that can be copypasted directly in Latex. PrintLatex:= function(M) for i in [1..NumberOfRows(M)] do for j in [1..NumberOfColumns(M)-1] do printf("%o &", M[i,j]); end…
AnalysisStudent0414
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An error occurs when computing a decomposition matrix of a factor group with MAGMA

I'd like to ask, if anybody can help me with the following: I entered this in MAGMA, but an error message (see below) appeared. G:=Alt(5); H:=sub; N:=Normaliser(G,H); H_in_N:=sub; FAC,f:=quo;…
Bernhard Boehmler
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Define a vector space for a given set on Magma.

This is probably an easy question, but I have been looking for hours before posting it. I want for a given finite set say $S$ (in particular a set of homogeneous polynomials), to define the vector space over a finite field $\mathbb{F}$ spanned from…
user430191
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Printing p-adic matrices in Magma CAS

I would like to print some p-adic matrices into a file that can then be read by magma. In theory this should be possible by using PrintFileMagma(..) but the problem I'm having is that the matrices are being produced by the pMatrixRing function which…
Chris Birkbeck
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Prime subfield enveloping algebra in Magma

Given a matrix group G $\leq$ GL(d, K), I can create the subalgebra of Mat$_{d}$(K) consisting of all K-linear combinations of the elements of G using the MatrixAlgebra constructor. I can't, however, create the subalgebra of Mat$_{d}$(K)…
user6834
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Computing $-\frac{655}{8}$ modulo 35 efficiently in Magma (CAS)

Modexp$(-81.875,1,35);$ will not work. So what I have to do is the following: Modexp$(-81,1,35); = 24$ $875/1000; = 7/8$ Modexp$(24*7,1,35); = 28$ Modexp$(8,-1,35); = 22$ Modexp$(22*28,1,35); = 21 \equiv −81.875 \mod 35$ But there has to be a…
Adam Staples
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Constructing a graph in Magma

I am trying to construct a simple graph in MAGMA and can't figure out how to get the syntax right. My code is below: triples := { : a, b, c in GF(7) | a^2 + b^2 - c^2 eq 0 }; G := Graph< triples | {<3, 3, 2>, <1, 6, 3>} >; The error I get…
stillconfused
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Substituting variables in MAGMA

If I have a polynomial $x_1+x_2+x_2x_3+x_2x_4$ and I want to rewrite it as $x_1+x_2+z_{2,3}+z_{2,4}$. Is there a function in MAGMA to substitute $x_2x_3$ as $z_{2,3}$? I know Maple has a subs function to do this but can't find the equivalent in…
tkw4063
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Permutation modules in MAGMA

I had a question about MAGMA: Let's say we have a permutation group $G$ acting on $\{1,2,\dots ,n\}$, and we construct the permutation module over a field $F$, by using $V:=PermutationModule(G,F);$. Then, when we pick a specific vector $v$ from $V$,…
vgmath
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Hadamard (entrywise) product in the Magma computer algebra system

Is it possible to efficiently compute the Hadamard product (= entrywise product) of 2 matrices in MAGMA? I can't find anything in the documentation. The best thing I can come up with is computing it directly with 2 nested for loops, but this is…
Ward Beullens
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