double indexed variable (new user)

2012 3 6
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I am very new to Matlab. I am trying to create ixj number of variables using the function below. I am getting an error message for pos(i,j) = [b/2+partsize/2+(i-1)*(b+partsize), b/2+partsize/2+(j-1)*(b+partsize)] line. How do I create indexed variables that I can call later in Matlab? Here pos(i,j)==> 1x2 vector (x and y coordinates) e.g I expect to obtain something like the following: pos (1,1)= [ 2 2] pos ( 1,2) = [2 4] pos ( 2,1) = [4 2] pos (2, 2) = [4 4] etc.
function b= posgen(cellsize, particleno, partsize)
partnoline =(particleno)^(1/2);
b= (cellsize-partnoline*partsize)/partnoline;
for i=1:partnoline;
for j=1:partnoline;
pos(i,j) = [b/2+partsize/2+(i-1)*(b+partsize), b/2+partsize/2+(j-1)*(b+partsize)]
end
end
What am I doing wrong? Can you help please

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Unknowndruid
Unknowndruid 2012-3-6
To make it simpler,
for i=1:n
for j=1:m
pos(i,j)=[n^2, m]
end
end
I want to create indexed variables and want to able to recall them their indexes with pos (2,3) or pos (1,5) etc.

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Walter Roberson
Walter Roberson 2012-3-6

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Numeric arrays cannot have multiple elements (e.g., x and y) at a location. Use an additional dimension, or use cell arrays.
pos(i,j,:) = [b/2+partsize/2+(i-1)*(b+partsize), b/2+partsize/2+(j-1)*(b+partsize)];

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Unknowndruid
Unknowndruid 2012-3-6
Thanks for rapid response!
I got the following error with the suggested change:
"Expression or statement is incomplete or incorrect."
Unknowndruid
Unknowndruid 2012-3-6
sorry my bad. It worked!!
But not the way I wanted:(
pos(:,:,1) =
2.5000
pos(:,:,2) =
2.5000
pos(:,:,1) =
2.5000 2.5000
pos(:,:,2) =
2.5000 7.5000
pos(:,:,1) =
2.5000 2.5000
7.5000 0
pos(:,:,2) =
2.5000 7.5000
2.5000 0
pos(:,:,1) =
2.5000 2.5000
7.5000 7.5000
pos(:,:,2) =
2.5000 7.5000
2.5000 7.5000
Unknowndruid
Unknowndruid 2012-3-6
Ok. I think that I am too new to understand the significance of this outcome. I now understand that I can recall pos (1,2,2) etc.

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