This essentially identical to the previous question I answered...
i want print column 2 4 5 45
Given array x of 50x50, say, and
icol=[2 4 5 45];
fmt=[repmat('%.3f ',1,length(icol)) '\n'];
fprintf(fid,fmt,x(:,icol).')
...
Again, salt to suit for formatting, etc., ...
ADDENDUM:
Unless the question is simply one of how to reference a subset of an array in which case the answer is embedded in the above by use of the predefined column index vector. This is basic Matlab syntax; if you don't understand that, go to the "Getting Started" section and work thru the basic addressing exercises.
NB: the line you've commented as giving an error is owing to the bad syntax that attempted to store the colon operator in the d vector. That may seem like a reasonable thing to try to do, but it is simply not supported by Matlab syntax.
d=(:,[2 4 5 45]); % you can't do this--invalid syntax w/ the 'colon'
Use the form demonstrated above instead.
NB2: You can't use
irow=[2 23 92];
icol=[2 4 5 45];
z=x(irow,icol);
however, despite it looking ok and being a desirable thing to do. In that case you'll have to use the two vectors as arguments to sub2ind. See the documentation for details on the whys and hows of that.
