Problems with #include<complex.h>

[JorgeM]

Hi there. I have been trying to implement complex.h library to make some calculations in c++.Anyways I am not sure why mi compiler does not run my code at all.

#include <iostream>
#include <complex.h>
#include <stdio.h>
using namespace std;
int main()
{
    double complex z = CMPLX(0.0, -0.0);
    cout<<" z = "<<creal(z)<<" + " <<cimag(z)<<endl;
    return 0;
}

Codeblocks says:
Error: expected initializer before z
Error: z was not declared in this scope
I am really confused because even in cpp.com this procedure for imaginary numbers is given.

If you could help me with how may I use, I would be really grateful.
Thanks a lot

 

[mfb]

double complex z

I don't know where you got that from but that cannot work. You are trying to assign a double called "complex", and then the compiler has no idea what to do with the z.
Here are examples how to do it
complex<double> z

 

[phyzguy]

I think you are mixing C and C++ usage. The following compiles and runs in C:

#include <complex.h>
#include <stdio.h>

int main()
{
double complex z = CMPLX(0.0, -0.0);
printf("z = %.1f%+.1fi\n", creal(z), cimag(z));
return 0;
}

The following code compiles and runs in C++:

#include <iostream>
#include <complex.h>
#include <stdio.h>
using namespace std;
int main()
{
complex<double> z(0.0, 0.0);
cout<<" z = "<<real(z)<<" + " <<imag(z)<<" i"<<endl;
return 0;
}