function source_out=interleaver(source_in)
%rem是求余數
%按列寫，按行讀


global  INTERLEAVERLENGTH

len=length(source_in);

cols=fix((len -1)/INTERLEAVERLENGTH) + 1; %一幀轉成列矩陣后的列數
theLastRowOfLastCol= rem( len -1 ,INTERLEAVERLENGTH) +1;  %最后一列的最后一行

for n=1:len        
    theCol=fix((n-1)/INTERLEAVERLENGTH) +1 ;
    theRow=rem(n-1,INTERLEAVERLENGTH) +1;
    if theRow>theLastRowOfLastCol
        index= theLastRowOfLastCol * cols  + (theRow - theLastRowOfLastCol -1) * (cols-1) + theCol;
    else
        index=(theRow -1) * cols + theCol;
    end
    source_out(index)= source_in(n);
end