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Can Magma compute secondary inviariants for a specified set of primary invariants?

The computer algebra system Magma has the functionality to compute a Hironaka decomposition for the invariant ring $R^G$ of a finite group $G$ acting linearly on a polynomial ring $R$, using the ...
2
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2answers
161 views

Symbolic computation vs. numerical computation

I am curious as to what the current status is for symbolic computation, and future outlooks as well. Here are some questions I would like to pose : What is the current outlook for symbolic ...
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0answers
42 views

Solving Equations By Reducing To One Variable

To solve an equation while creating a computer algebra system, is it reasonable to take all the variables in a given system and (using equations already given) replace them with one arbitrary ...
4
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3answers
98 views

Benchmarks for Gröbner bases and polynomial system solution

In the recent question Solving system of 7 nonlinear algebraic equations symbolically, Brian Borchers experimentally confirmed that Maple can solve a polynomial system that Matlab/Mupad cannot handle. ...
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0answers
71 views

How to construct a subring of a polynomial ring in Magma

This is a question about the computer algebra system Magma. I have been looking for a place to ask this type of question on the SE network and scicomp.SE was suggested to me; hopefully it finds a home ...
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0answers
119 views

General algorithm to solve systems of symbolic equations

I want to simplify (solve) a system of linear + nonlinear symbolic equations as much as possible. the equations are of random orders, without differentiation. is there a general & well-known ...
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1answer
135 views

MATLAB: Backslash operator using symbolic variables with an overdetermined system

I have an overdetermined system (too many equations), expressed as Ax=b, in MATLAB. When I try to solve it using A\b, I receive the error: ...
2
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1answer
268 views

Saving symbolic function to increase efficiency in Matlab

I have a lengthy expression which is calculated using symbolic differentiation of a rather complicated function. I now intend to call this resulting (symbolic function) in a for loop many times, and ...
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4answers
554 views

Seeking a free symbolic regression software

Now that Formulize / Eureqa started charging $2500 a year for using it and having crippled the trial version, does anyone know of any replacements that can do similar things like find an equation ...
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1answer
302 views

Symbolic Computations with Block Matrices in Maple

Due to the derivation of an algorithm I tried to use Maple (9.5) to calculate some block matrix expression. Unfortunately Maple seems to ignore the assumption I set on the variable. Lets consider the ...
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3answers
338 views

Looking for ways to speed up the numeric evaluation of a symbolic expression in Matlab

{Summary: I have a symbolic expression DCritnF expressed in terms of two variables x1 and x2. I need to find it's numeric value and I used combination of double and subs as given below. ...
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2answers
224 views

Systems of nonlinear equations

Consider the nonlinear system of equations $$ (1) \quad qk^2a_1^2E^2+wna_0a_1AE+pnka_0^2a_1E+rn^2a_0^2A^2-rn^2a_0^3A^2+qk^2a_0a_1ABE-qk^2na_0^2E^2=0, $$ $$ (2) \quad ...
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0answers
74 views

CAS to perform “simple” tensor operations in index notation

Heres a couple of questions, 1) Does a CAS exist that can manipulate Cartesian based tensors and produce a simplified output that is hopefully in index notation? 2) If not, is there some indirect ...
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2answers
201 views

How can I teach Maxima to use units?

I want to do engineering and scientific calculations im Maxima/wxmaxima. I do not want to manually check every time if my units make sense, how can I achieve this? I'm looking at Maxima because it's ...
3
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1answer
65 views

Minimizing expression DAGs

Say I have an expression involving adds, subtractions, and multiplications. I know that it is safe to assume commutativity, associativity, distributivity, etc., and would like to automatically ...
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0answers
113 views

What libraries are available for solving problems at the college physics level?

Are there any libraries available for solving problems at the level of college physics? In particular, I'm interested in libraries for general purpose programming languages that can calculate results ...
1
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1answer
388 views

How easy is it to combine symbolic and numeric computation in Matlab?

CS Beta people: I have been doing some multiple integrals with a combination of symbolic and numerical integration (because symbolic answers have not always been possible). I have been using ...
3
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1answer
88 views

Simple substitutions using symbolic computing in MATLAB

Suppose I have the following MATLAB code. syms a b c1 c2 c1 = a + b + pi*b c2 = a + b + 0.5*b Then c1 gets evaluated to ...
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5answers
1k views

Symbolic solution of a system of 7 nonlinear equations

I've got a system of ordinary differential equations - 7 equations, and ~30 parameters governing their behavior as part of a mathematical model of disease transmission. I'd like to find the steady ...
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8answers
787 views

Is there any open-source or easy-to-access software that can simplify algebraic expressions like $x^{2}+2x+3, x=\sqrt{2}t-1$?

I always calculate things by hand, but now my comrades are getting nasty and making a lot of repetitive exercises involving just plugging things in like the expression above. I am particularly ...
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2answers
678 views

Automatic generation of integration points and weights for triangles and tetrahedra

Usually one would consult a paper or book to find integration points and weights for unit triangle and tetrahedra. I am looking for a method to automatically compute such points and weights. The ...
32
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6answers
1k views

Symbolic software packages for Matrix expressions?

We know that $\mathbf A$ is symmetric and positive-definite. We know that $\mathbf B$ is orthogonal: Question: is $\mathbf B \cdot\mathbf A \cdot\mathbf B^\top$ symmetric and positive-definite? ...