SELECTED_REAL_KIND Function

Description

The SELECTED_REAL_KIND function returns the kind type parameter of a REAL data type with decimal precision of at least p digits and a decimal exponent range of at least r.

Syntax
 
SELECTED_REAL_KIND ([p] [, r])
 

Optional Arguments

p is an INTENT(IN) scalar INTEGER, representing the requested precision.

r is an INTENT(IN) scalar INTEGER representing the requested exponent range.

At least one argument must be present.

Result

The result is a scalar default INTEGER. Its value is equal to the processor dependent kind type parameter of the REAL data type with decimal precision of at least p digits and a decimal exponent range of at least r.

If more than one kind is available, the return value is the value of the kind type parameter of the kind with the smallest decimal precision.

The result is -1 if the precision is not available, -2 if the range is not available, and -3 if neither is available.

Example
       ! request a precision
       write(*,*) selected_real_kind(p=6)  ! writes 4
       write(*,*) selected_real_kind(p=12) ! writes 8
       write(*,*) selected_real_kind(p=24) ! writes 16
       write(*,*) selected_real_kind(p=48) ! writes -1
       ! request a range
       write(*,*) selected_real_kind(r=10)    ! writes 4
       write(*,*) selected_real_kind(r=100)   ! writes 8
       write(*,*) selected_real_kind(r=1000)  ! writes 16
       write(*,*) selected_real_kind(r=10000) ! writes -2
       write(*,*) selected_real_kind(r=10000,p=48) ! writes -3