faster way to sum desired matrix elements in matlab

Just works

g = rand(5)
p = blkdiag(1,1,0,1,1)

index = find(p~=0)

sum(g(index))

Copy File using command/script in Matlab

This one comes handy when you have repetitive work to copy the files to some directory.

I had to conduct different tests with different parameters and hence wanted an automated way to clean up the files after each test. I wanted to have them organized in folder as per attribution.

This is how I copied my file:
Untitled.m into the folder

mkdir destination_folder

[s,mess,messid]=copyfile('Untitled.m','destination_folder')

see help copyfile feature for details.

This is quite stunning to realize that Matlab has unix features such as ls and pwd
while not cp or mv for copying the files. I started by assuming that cp or mv should work. It does not!
After I copy the files, I can:

delete('Untitled.m')

%%%%%%%%%%%%%%%%%%%%%%%%%%-------------%%


function clean_up_fig

jj = 'test';
%%
cd G1_OK
mkdir(jj)

copyfile('*.fig',jj)
copyfile('*.tif',jj)
copyfile('*.mat',jj)

delete('*.tif')
delete('*.fig')

cd ..

Get desired elements from the given array in Matlab

A very simple function to collect the items from the array which meets the required condition

clear all
A=[1,2,3,4,5,6,7,8,9,10];
B=zeros(1,length(A));
k=1;
diff = A(1);
B(1) = diff;
for i=2:length(A)
diff=diff+3;
    B(i) = diff;

end
B = B(B<=max(A))