tangent function

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NAME

tan

INTERFACE

#include <math.h>

double tan ( double x ) long tanl ( long double x ) float tanf ( float x )

DESCRIPTION

The tan function computes the tangent of x (measured in radians).

Example 1

#include <math.h>
#include <stdio.h>

  int main(void)
  {
    double val = -1.0;

    do {
      printf("Tangent of %f is %f.\n", val, tan(val));
      val += 0.1;
    } while(val<=1.0);

    return 0;
  }

output

Tangent of -1.000000 is -1.557408.
Tangent of -0.900000 is -1.260158.
Tangent of -0.800000 is -1.029639.
Tangent of -0.700000 is -0.842288.
Tangent of -0.600000 is -0.684137.
Tangent of -0.500000 is -0.546302.
Tangent of -0.400000 is -0.422793.
Tangent of -0.300000 is -0.309336.
Tangent of -0.200000 is -0.202710.
Tangent of -0.100000 is -0.100335.
Tangent of 0.000000 is 0.000000.
Tangent of 0.100000 is 0.100335.
Tangent of 0.200000 is 0.202710.
Tangent of 0.300000 is 0.309336.
Tangent of 0.400000 is 0.422793.
Tangent of 0.500000 is 0.546302.
Tangent of 0.600000 is 0.684137.
Tangent of 0.700000 is 0.842288.
Tangent of 0.800000 is 1.029639.
Tangent of 0.900000 is 1.260158.
Tangent of 1.000000 is 1.557408.

SPECIAL VALUES

tan ( ±0 ) returns ±0.
tan (±&infin; ) returns a NaN and raises the invalid floating-point exception.

SEE ALSO

acos (3) , asin (3) , atan (3) , atan2 (3) , cos (3) , cosh (3) , sin (3) , sinh (3) , tanh (3)

STANDARDS

The tan function conforms to ISO/IEC 9899:1999(E).