# catanf, catan, catanl

< c‎ | numeric‎ | complex

C
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Complex number arithmetic
Types and the imaginary constant
Manipulation
Power and exponential functions
Trigonometric functions
 cacos casin catan
Hyperbolic functions

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Defined in header `<complex.h>`
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float complex       catanf( float complex z );
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double complex      catan( double complex z );
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long double complex catanl( long double complex z );
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Computes the complex arc tangent of `z` with branch cuts outside the interval [−i,+i] along the real axis.

## Contents

### Parameters

 z - complex argument

### Return value

The complex arc tangent of `z` in the interval (−∞; ∞) along the imaginary axis and in the interval [−π/2; +π/2] along the real axis.