MATLAB: Matrix padding with logical index

indexingpadding

I have a matrix(6 by 3) of different row lengths:
    0.9969    0.9724    0.3951
    0.3590    0.5865    0.3983
    0.6252    0.7780    0.7513
       NaN    0.7277    0.5224
       NaN       NaN    0.4904
       NaN       NaN    0.0887
and a logical index matrix that has same or longer row length(7 by 3) like:
     1     0     1
     1     1     1
     0     1     0
     0     0     1
     0     1     1
     0     1     1
     1     0     1
how can I get the following results(7 by 3) without loop:
    0.9969         0    0.3951
    0.3590    0.9724    0.3983
         0    0.5865         0
         0         0    0.7513
         0    0.7780    0.5224
         0    0.7277    0.4904
    0.6252         0    0.0887
Thanks very much in advance

Best Answer

Assuming that the first array is A, the logical array is B, and you want to build C:
 C = zeros( size( B )) ;
 C(find( B )) = A(~isnan( A )) ;
EDIT : if, for any reason, you needed the row index in A of elements of C, you could get them as follows
 >> cumsum( B ) .* B
 ans =
     1     0     1
     2     1     2
     0     2     0
     0     0     3
     0     3     4
     0     4     5
     3     0     6
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