# Evaluating a polynomial matrix

**URL:** https://discourse.julialang.org/t/evaluating-a-polynomial-matrix/117472
**Category:** New to Julia
**Created:** [July 25, 2024, 1:26pm UTC](https://discourse.julialang.org/t/evaluating-a-polynomial-matrix/117472 "2024-07-25T13:26:09Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![Banan\_alkafri](https://avatars.discourse-cdn.com/v4/letter/b/85f322/32.png) [@Banan\_alkafri](https://discourse.julialang.org/u/Banan_alkafri)
#### Post date: [July 25, 2024, 1:26pm UTC](https://discourse.julialang.org/t/evaluating-a-polynomial-matrix/117472/1 "2024-07-25T13:26:09Z")

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Hello,  
I’m trying to evaluate a polynomial matrix given by sol[5] in my code at certain values of x and y which I generated using LinRange. I tried to do it, but I’m getting the indices of sol[5] rather that the value of the matrix at any pair (x,y). Here is my code:

x = LinRange(0, 10, 20)  
y = LinRange(0, 10, 20)

polynomial\_matrix = sol[5]  
for i in 1:length(x)  
for j in 1:length(y)  
xi = x[i]  
yj = y[j]  
polynomial=polynomial\_matrix[xi,yj]

end  
end

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<div class="post-metadata">

### Author: ![nsajko](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/nsajko/32/221187_2.png) [@nsajko](https://discourse.julialang.org/u/nsajko)
#### Post date: [July 25, 2024, 2:09pm UTC](https://discourse.julialang.org/t/evaluating-a-polynomial-matrix/117472/2 "2024-07-25T14:09:23Z")

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> [@Banan\_alkafri](#):
>
> `polynomial_matrix[i, j]`

Perhaps you meant `polynomial_matrix[xi, yj]`. BTW, try to use Markdown to properly format the code in your post.