[minor] Typos

Author: BastienTr

commpy/channelcoding/tests/test_ldpc.py

@@ -99,4 +99,4 @@ def test_triang_ldpc_systematic_encode(self):
                 decoded_bits[i * block_length:(i + 1) * block_length] = \
                     ldpc_bp_decode(coded_bits[:, i], param, 'SPA', 10)[0][:block_length]
             assert_equal(decoded_bits[:len(message_bits)], message_bits,
-                         'Encoded and decoded message does not match the initial bits without noise')
+                         'Encoded and decoded messages do not match the initial bits without noise')