some confusions when testing the source code prf_lbm.cpp

[hank9cao]

Hi Jiayu:

I was testing the proximal operator for the L1inf norm which lead me to test the prf_lbm.cpp.
First, it worked well, and the procedure to make sparsity is quite similar to the procedure in Sparse PCA.
But I found some source codes doesn't match the performance, here is my testing:
D=[1 2 2; 4 4 3];
tau=1;
[mu, theta , mc]=prf_lbm(D,2,3,tau);
Then

mu =

     0    0.5000    0.5000
0.5000    0.5000         0

theta =

1.5000
3.5000

The results seems quite right. But in the source code(line 94 ):
x[im+j] = (c[im+j] > theta)?(c[im+j]-theta):((c[im+j]< -theta)?(c[i*m+j]+theta):0);
when theta=1.5
mu(1,:) should be -0.5 0.5 0.5 in stead of 0 0.5000 0.5000

Please let me know, why is this?

Regards,
Hank