# cabsf, cabs, cabsl

< c‎ | numeric‎ | complex

C
 Language headers Type support Dynamic memory management Error handling Program utilities Variadic function support Date and time utilities Strings library Algorithms Numerics Input/output support Localization support Thread support (C11) Atomic operations (C11) Technical Specifications

Complex number arithmetic
Types and the imaginary constant
Manipulation
 cabs conj cproj
Power and exponential functions
Trigonometric functions
Hyperbolic functions

 Defined in header `` float       cabsf( float complex z ); (1) (since C99) double      cabs( double complex z ); (2) (since C99) long double cabsl( long double complex z ); (3) (since C99) Defined in header `` #define fabs( z ) (4) (since C99)
1-3) Computes the complex absolute value (also known as norm, modulus, or magnitude) of `z`.
4) Type-generic macro: if `z` has type long double complex or long double imaginary, `cabsl` is called. If `z` has type float complex or float imaginary, `cabsf` is called. If `z` has type double complex or double imaginary, `cabs` is called. For real and integer types, the corresponding version of fabs is called.

## Contents

### Parameters

 z - complex argument

### Return value

If no errors occur, returns the absolute value (norm, magnitude) of `z`.

Errors and special cases are handled as if the function is implemented as hypot(creal(z), cimag(z))

### Example

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

int main(void)
{
double complex z = 1.0 + 1.0*I;
printf("%.1f%+.1fi cartesian is rho=%f theta=%f polar\n",
creal(z), cimag(z), cabs(z), carg(z));
}```

Output:

`1.0+1.0i cartesian is rho=1.414214 theta=0.785398 polar`

### References

• C11 standard (ISO/IEC 9899:2011):
• 7.3.8.1 The cabs functions (p: 195)
• 7.25 Type-generic math <tgmath.h> (p: 373-375)
• G.7 Type-generic math <tgmath.h> (p: 545)
• C99 standard (ISO/IEC 9899:1999):
• 7.3.8.1 The cabs functions (p: 177)
• 7.22 Type-generic math <tgmath.h> (p: 335-337)
• G.7 Type-generic math <tgmath.h> (p: 480)