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Hello,

I have a big problem and I don't know how to resolve it.

I have two matrices: A and B. I want to use B[1] as an index of A ,i.e., 

B[1] := [1, 1]; Ok

A[B[1]]; But this does'nt work. 

Thanks for your help...

I need this quite often, but never found a nice way of getting the index of minimal or maximal value of a Vector (or a list or whatever). Is there an easier way than the following?

N := 15:
L := LinearAlgebra[RandomVector](N):
m := min(L):
for i to N do if L[i] = m then print(i); break end if end do;

Hi. I have a question that concerns indices of vector of functions within for-loop.

I have a following piece of code:

I wrote a procedure that solves a volterra integral equation numerically. This procedure  takes N , number of radial basis functions, as parameter  .the problem is:Error,  bad index into Matrix

How can I fix this problem?

here is my procedure:

I would like to index Variable names like how it is common in physics (just as an addition to the variable name to distinct between say t_a and t_b just as two different times). However i am not sure how to do this and make maple treat for example t_a EXACTLY like if it would be called ta.

int(1/2*m*(-x[b]+x[a])^2/(-tb+ta)^2,t = ta .. tb)

is evaluated but

int(1/2*m*(-x[b]+x[a])^2/(-t[b]+t[a])^2,t = t[a] .. t[b])

restart;
lucoef:=Array(0..4, (i->i^2+3));
j:=1;
lucoefnew:=sum (lucoef[r]*lucoef[j-r],r=0..j);

Error, bad index into Array

===========
What it wants from me?!

Hiim using maple 14 and tried to apply the sum of vector's elements, y appears a error (Error, unsupported type of index, n)

a := Vector(5, {(1) = 1, (2) = 2, (3) = 3, (4) = 4, (5) = 5});
> sum(a(n), n = 1 .. 5);

Error, unsupported type of index, n

please need some help

Thanks

Hi,

I need to do this:

A:=[1,3,5,2,7];
B:=[2,5];

f(B,A)=[3,7]

Notice that the elements in A can be lists themselves. How can I define such kind of function?

TIA for the help

If I have the following expression 

K:=(j)->j  is an expression where j an index run from 1 to 10

Now, I want to fill a row matrix with this expression as follows

A := Matrix(1, 10, K)

I think this is true where the result is [ 1  2  3  4  ..... 10]

but this is not  true in maple

the result is     [1  1  1  1 ..... 1] 

can any one tell what is the truth.

Is there a direct command to give the (first) index in a list,
for which the entry coincides with some given value (without
coding a loop, to run through the list)?

---

PS: when I enter that question I automatically get an info,
that similar questions exists. But clicking on those links do
not give usefull infos, they just lead to a page of old threads
(Page 529 of 569 for the first link ...)