Source
void transpose() {
double temp;
temp = _m4storage[4];
_m4storage[4] = _m4storage[1];
_m4storage[1] = temp;
temp = _m4storage[8];
_m4storage[8] = _m4storage[2];
_m4storage[2] = temp;
temp = _m4storage[12];
_m4storage[12] = _m4storage[3];
_m4storage[3] = temp;
temp = _m4storage[9];
_m4storage[9] = _m4storage[6];
_m4storage[6] = temp;
temp = _m4storage[13];
_m4storage[13] = _m4storage[7];
_m4storage[7] = temp;
temp = _m4storage[14];
_m4storage[14] = _m4storage[11];
_m4storage[11] = temp;
}