Updating a matrix using a for loop and if clause. Causing expression to the left of the equals sign is not a valid target for an assignment.

Hi all,

I'm trying to update a matrix so that values increment when another value is present in another dataset. However it seems that data(1,i) is not a valid target for an assignment. I can't seem to find out why. Any help is much appreciated.

xinc = 0.03125;
yinc = 0.015625;
zinc = 0.03125;
xnew = 0.5;
ynew = 0.25;
znew = 0.5;

data = zeros(3,5000);

for i = 1:1:5000
    if(Seed0Orange(251,i) == 100);
        {

               data(i,1) = xnew;
               xnew = xinc + xnew;
               data(i,2) = ynew;
               ynew = ynew + xinc;
               data(i,3) = znew;
               znew = znew + zinc;
          }
      end
  end

Answer 1

[Iain]

The problem is that you have included

 { and } around the code. Remove those and it'll work.

Answer 2

[Andrei Bobrov]

add = [0.03125,0.015625,0.03125];
d1 = [0.5,0.25,0.5];

t = Seed0Orange == 100;
n = nnz(t);
data = zeros(3,5000);
data(t,:) = cumsum([d1;ones(n-1,1)*add]);