Complex numbers
Complex numbers are represented using the type gsl_complex
. The
internal representation of this type may vary across platforms and
should not be accessed directly. The functions and macros described
below allow complex numbers to be manipulated in a portable way.
For reference, the default form of the gsl_complex
type is
given by the following struct,
typedef struct
{
double dat[2];
} gsl_complex;
The real and imaginary part are stored in contiguous elements of a two
element array. This eliminates any padding between the real and
imaginary parts, dat[0]
and dat[1]
, allowing the struct to
be mapped correctly onto packed complex arrays.
- Function: gsl_complex gsl_complex_rect (double x, double y)
-
This function uses the rectangular cartesian components
(x,y) to return the complex number z = x + i y.
- Function: gsl_complex gsl_complex_polar (double r, double theta)
-
This function returns the complex number z = r \exp(i \theta) = r
(\cos(\theta) + i \sin(\theta)) from the polar representation
(r,theta).
- Macro: GSL_REAL (z)
-
- Macro: GSL_IMAG (z)
-
These macros return the real and imaginary parts of the complex number
z.
- Macro: GSL_SET_COMPLEX (zp, x, y)
-
This macro uses the cartesian components (x,y) to set the
real and imaginary parts of the complex number pointed to by zp.
For example,
GSL_SET_COMPLEX(&z, 3, 4)
sets z to be 3 + 4i.
- Macro: GSL_SET_REAL (zp,x)
-
- Macro: GSL_SET_IMAG (zp,y)
-
These macros allow the real and imaginary parts of the complex number
pointed to by zp to be set independently.