====== csqrt ====== double complex csqrt(double complex z); ==== description of csqrt ==== calculate the complex squareroot #include #include int main( void ) { long double complex zlong=4.2 + I*2.34; double complex zdouble=(double complex)zlong; double result; result = csqrt(zdouble); printf("csqrt(%f + I*%f) = %f\n", creal(zdouble), cimag(zdouble), result); return 0; } ===== output of csqrt c example ===== csqrt(4.200000 + I*2.340000) = 2.122247