from Girth 4 test for LDPC codes by Yang Xiao
We need to know that Girth 4 of H will lead to a poor BER performance. The program can test whether

All files for Girth 4 test for LDPC codes
/LDPC_Girth4 Test/B1.txt
/LDPC_Girth4 Test/LDPC_girth4a.m
/license.txt

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