# Inverse of a cell array

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MarshallSc on 6 Jul 2021
Answered: the cyclist on 6 Jul 2021
Hello, I'm trying to get the inverse values of a 10*10 cell array, each containing a 4*4 matrix. The code is (credit to Stephen Cobeldick for the code):
x1 = rand(10,10);
y1 = rand(10,10);
z1 = rand(10,10);
r1 = rand(10,10);
a1 = cat(3,x1,y1,z1,r1);
x2 = rand(10,10);
y2 = rand(10,10);
z2 = rand(10,10);
r2 = rand(10,10);
a2 = cat(4,x2,y2,z2,r2);
tmp = num2cell(sqrt(a1./a2),3:4);
fun = @(a)reshape(a,4,4);
out = cellfun(fun,tmp,'uni',0);
Now I want the inverse of the results (1/values). I used some commands but the results are not accurate. For example using:
out2=cellfun(@inv, out, 'uniform', 0);
But the results are not correct. Is there any method that can calculate the inverse of the cell array? Thank you.

the cyclist on 6 Jul 2021
Do you mean you want the reciprocal of each element of each matrix? (That is not what the inverse of a matrix means.)
If so, then you want
x1 = rand(10,10);
y1 = rand(10,10);
z1 = rand(10,10);
r1 = rand(10,10);
a1 = cat(3,x1,y1,z1,r1);
x2 = rand(10,10);
y2 = rand(10,10);
z2 = rand(10,10);
r2 = rand(10,10);
a2 = cat(4,x2,y2,z2,r2);
tmp = num2cell(sqrt(a1./a2),3:4);
fun = @(a)reshape(a,4,4);
out = cellfun(fun,tmp,'uni',0);
out2=cellfun(@(x) 1./x, out, 'uniform', 0);
% example of one reciprocal:
out{1}
ans = 4×4
0.5451 0.3943 0.6951 0.5691 1.1282 0.8162 1.4386 1.1779 0.1688 0.1221 0.2152 0.1762 0.7559 0.5469 0.9639 0.7893
out2{1}
ans = 4×4
1.8345 2.5359 1.4387 1.7571 0.8864 1.2252 0.6951 0.8490 5.9252 8.1905 4.6467 5.6751 1.3228 1.8286 1.0374 1.2670