How to find position a input

Hello!

I have this function

function z = testpapa(x, y,xx,yy)

z = zeros(2,2,2,2);
for m=1:length(x)
    for n=1:length(y)
        for i=1:length(xx)
             for ii=1:length(yy)  
        z(m,n,i,ii) =  (x(m)).^4'* sin(y(n)).^3'*cos(xx(i)).^2'*(yy(ii));
             end
        end
    end
end
end

When implementing a function, I picked one value, but what I want is the input position of each one that brings out this value. how to find position a input (x y xx yy).

x = 5:1:6; y = 7:1:8; xx = 9:1:10; yy = 11:1:12;
fcn = testpapa(x,y,xx,yy);
V =0.1264; % required value
dif = abs(fcn-V);
minMatrix = min(dif(:));
[row;col;roll;coll] = find(dif==minMatrix);

Thanks for everyone's answers.

Answer 1

[Jan]

z(m,n,i,ii) =  (x(m)).^4'* sin(y(n)).^3'*cos(xx(i)).^2'*(yy(ii));
% Voodoo:      ^    ^^  ^           ^  ^           ^  ^ ^      ^

% Cleaner:
z(m,n,i,ii) =  x(m)^4 * sin(y(n))^3 * cos(xx(i))^2 * yy(ii);

You could omit the loops also:

z = x(:).^4 .* sin(y(:).').^3 .* ...
    reshape(cos(xx).^2, 1, 1, []) .* reshape(yy, 1, 1, 1, []);

I'm not sure if this is nicer.

V   = 0.1264; % required value
dif = abs(fcn - V);
[minDif, iLinear] = min(dif(:));
[i1, i2, i3, i4] = ind2sub(size(dif), find(dif == minDif))

[yanisa ketsuwan]

You’re so helpful. Thanks a lot.

Can I ask you something? I want the position xx at V So wrote " xx(i3) ". I'm not sure if I understand it correctly.

[Jan]

Yes, this is correct: The minimal distance it found at x(i1), y(i2), xx(i3), yy(i4).

[yanisa ketsuwan]

That’s very kind of you