Append Data to Array of Cell

Hi Guys, Again I need your help. Due to any reason I cannot append data to an array in a cell within every round of a for-loop. I'd like to do the following, what should actually work, if looking at help:

R{i,7}(:,1) = [R{i,7}(:,1); (ceil(R{i,1}(j,10)/increment)*increment          :increment:floor(R{i,1}(j+1,10)/increment)*increment          )'; R{i,1}(j+1,10)];

Matlab throws the error Subscripted assignment dimension mismatch. So I tried the following, but the same error appears.

R{i,7}(:,1) = vertcat(R{i,7}(:,1), (ceil(R{i,1}(j,10)/increment)*increment          :increment:floor(R{i,1}(j+1,10)/increment)*increment          )', R{i,1}(j+1,10));

Can anyone help me with my problem? Thanks in advance!

Georg

Answer 1

[Walter Roberson]

You cannot increase the number of rows in a variable by using

variable(:, column) = more_data_than_before

When you have an existing array, the : index in the first position expands to 1 : size(existing_array,1) -- a definite size, and you cannot store more data than that there.

It is only when you are storing to an array that has not been initialized that you can use : and have it build the array as big as required.

You will need to use:

newdata = [(ceil(R{i,1}(j,10)/increment)*increment          :increment:floor(R{i,1}(j+1,10)/increment)*increment          )'; R{i,1}(j+1,10)];

R{i,1}(end+1:end+size(newdata,1), 1) = newdata;

Note that if R{i,1} has more than one column, this would put 0 in those columns in the expanded rows.

[Georg Söllinger]

Hello Mr. Roberson,

Thanks for your answer, this solution works!! Indeed, it was also my guess, that it s the :, who causes trouble...

Thanks again, best wishes!