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2
votes
1answer
64 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 ...
1
vote
1answer
29 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 ...
1
vote
1answer
67 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 ...
0
votes
3answers
156 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. ...
0
votes
2answers
138 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 ...
2
votes
0answers
44 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 ...
3
votes
2answers
105 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
votes
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 ...
1
vote
0answers
94 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
vote
1answer
215 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
votes
1answer
85 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 ...
8
votes
5answers
893 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 ...
16
votes
7answers
673 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 ...
11
votes
2answers
458 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 ...
28
votes
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? ...