Filtered BackProjection Matlab

Question

I have already implemented the code for BackProjection and it works. Now I have to implement the code for the filtered version, using first ramlak filter and then hamming window. My sinogram has dimension 144x180. My idea is

filter=zeros(1,144)';

filter(1:73)=[0:1/72:1];

filter(74:end)=[1-1/72:-1/72:1/72];

in order to have an filter like this

and then for each projection s

filtered_proj=fft(s).*filter;
proj=real(ifft(filtered_proj));

and then performing the backprojection algorithm

Could you please tell me if it is correct?

Thank you