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evalf...

vv 11818
June 08 2022
2 1

If the matrix A has both exact and float entries, then it is obvious that some computations (e.g. the value of a discontinuous function) may return "unexpected" results.
Rank is such a discontinuous function. You have to accept this fact.
E.g. if A has two columns such that the first one is symbolic with at least an irrational entry,
and the second column is nonzero with float entries, the rank(A) is always 2.

> 

restart;
> 

v:=<sqrt(3), 2, 0>:
> 

A:=<v|evalf[25](v)>;

Matrix(3, 2, {(1, 1) = sqrt(3), (1, 2) = 1.732050807568877293527446, (2, 1) = 2, (2, 2) = 2., (3, 1) = 0, (3, 2) = 0.})

 (1)
> 

LinearAlgebra:-Rank(A);        # exact

2

 (2)
> 

LinearAlgebra:-Rank(evalf(A)); # "approx" but probably "expected"

1

 (3)

 

Just replace in param1,...,param4: ...

vv 11818
June 06 2022
1 0

Just replace in param1,...,param4:  alpha*gamma=0.004;   with   gamma=0.004/alpha;
(or use algsubs).

Advices:
- don't load packages which are not needed
- gamma is a Maple constant, don't use it as a variable
- linalg is deprecated; use LinearAlgebra instead.

 

Int...

vv 11818
June 06 2022
4 3 
convert(EllipticK(x), Int): 
eval(%,x=1); value(%);

       

          infinity

size...

vv 11818
June 04 2022
2 2 
with(GroupTheory):
g:=DrawSubgroupLattice(SmallGroup(200, 31), labels = ids, output=graph):
GraphTheory:-DrawGraph(g, size=[1200,800]);