How I can save vectors in for loops

Dears, I want to know how can I save vectors in 3(or more) for loops My code is huge and I summarize it here.

for i=1:10
   for j=1:15
      for k=1:20
      % some calculation
      Vector1= something with size(1x2000) % size of Vector1 will be changed in each loop
      end
   end
end

finally I would like to attach all of Vector1 to one vector and capable to find the special array is related to which i and j and k.

Answer 1

[Star Strider]

Since the length of the vector will change in each loop, I would use a cell array and a counter:

k1 = 0;
for i=1:10
   for j=1:15
      for k=1:20
      % some calculation
      k1 = k1 + 1;
      Vector1{k1} =  something with size(1x2000) % size of Vector1 will be changed in each loop
      end
   end
end

[Sam sanati]

Thanks Star Strider,

What about to recall the special array related to i,j,k. In other words after calculation of the all of Vector1. for example size (1x2000),(1x2500),(1x3200) ... , the Vector1total (which size is sum of all 2000+2500+3200+ ...) how can I find the special array. Imagine that for example array equal to 2 is nth array in the vector1total (1x2000+2500+3200...). how we can find that is related to which array of which vector1?

[Star Strider]

I do not understand your question, so I am not certain this will answer it.

You can keep whatever information you want in your cell array. For instance if you have:

x1 = (1x2000)
x2 = (1x2500)
x3 = (1x3200)
xc = [x1  x2  x3]     % Concatenate Vectors

and you want to save the indices i,j,k as well, you can create ‘Vector1’ as:

Vector1{k1} = {i, j, k, xc};

or whatever you want in it.

[Sam sanati]

Thanks for your quick reply and apologize for bad explanation. There is 2 question:

1- how to concatenate vectors in for loops? The number of vectors is too much (for example n is 2000).

xc=[x1 x2 ... xn]

I can not concatenate after end of last for.

2- after creation of xc, the n th array of xc (for example 12567 th) should be determine the related i,j and k.

Thanks again

[Star Strider]

My pleasure. Your explanation is not ‘bad’, sometimes it is not easy to describe what what we want our code to do.

If I understand you correctly:

1. The length of your vector (‘xc’ in my example) is determined by your computer’s memory. I do not know what you are calculating, so I cannot suggest a more efficient strategy.

2. In my example, i,j,k are stored as part of the cell element. If you want the cell array ‘Vector1’ to have 3 dimensions instead of 1, you can easily do that:

Vector1{i,j,k} = xc;

Then you can address each element individually. (You do not need the ‘k1’ counter if you do this.)