View Compilation Error

0_0_18188107_14471.cpp: In function 'int getRank(double (*)[301], int, int)':
0_0_18188107_14471.cpp:70:34: error: invalid operands of types 'double' and 'double' to binary 'operator^'
                     matrix[j][k] ^= matrix[r][k];
                                  ^
0_0_18188107_14471.cpp:70:34: error:   in evaluation of 'operator^=(double, double)'