# asin(x): Trigonometric Arcsine¶

Trigonometric arcsine function.

## Declaración¶

### Sintaxis¶

retval = asin(x)
elemental real(p) function asin(x)
elemental complex(p) function asin(x)


### Argumentos¶

x the input value, can be real or complex; less than or equal to 1.

### Valores devueltos¶

The returned value has the kind of the input value and TYPE may be real or complex.

## Descripción¶

asin(x) computes the arcsine of the argument x.

The arcsine is the inverse function of the sine function. It is commonly used in trigonometry to find the angle when the lengths of the hypotenuse and the opposite side of a right triangle are known.

## Tipos¶

Supported argument types float, double, complex float, complex double.

interface asin
module procedure sasin, dasin, casin, zasin
end interface

contains

interface
elemental real(sp) function sasin(x)
real(sp), intent(in) :: x
end function

elemental real(dp) function dasin(x)
real(dp), intent(in) :: x
end function

elemental complex(sp) function casin(x)
complex(sp), intent(in) :: x
end function

elemental complex(dp) function zasin(x)
complex(dp), intent(in) :: x
end function
end interface


## Ejemplos¶

program intrinsics_asin
implicit none
integer, parameter :: arg_x = kind(0.0)
real(arg_x) :: x1
real :: retval_x
real :: arg_x
retval_x = asin(0.84147098)
print *, ret_val_x
retval_x = asin(x1)
print *, ret_val_x
end program


Result:

0.99999
0.99999


acos, atan.