9.51 BTEST — Bit test function

Description:

BTEST(I,POS) returns logical .TRUE. if the bit at POS in I is set. The counting of the bits starts at 0.

Standard:

Fortran 95 and later, has overloads that are GNU extensions

Class:

Elemental function

Syntax:

RESULT = BTEST(I, POS)

Arguments:

I	The type shall be INTEGER.
POS	The type shall be INTEGER.

Return value:

The return value is of type LOGICAL

Example:

          program test_btest
              integer :: i = 32768 + 1024 + 64
              integer :: pos
              logical :: bool
              do pos=0,16
                  bool = btest(i, pos)
                  print *, pos, bool
              end do
          end program test_btest

Specific names:

Name	Argument	Return type	Standard
BTEST(I,POS)	INTEGER I,POS	LOGICAL	F95 and later
BBTEST(I,POS)	INTEGER(1) I,POS	LOGICAL(1)	GNU extension
BITEST(I,POS)	INTEGER(2) I,POS	LOGICAL(2)	GNU extension
BJTEST(I,POS)	INTEGER(4) I,POS	LOGICAL(4)	GNU extension
BKTEST(I,POS)	INTEGER(8) I,POS	LOGICAL(8)	GNU extension