BTEST — Bit test function¶

BTEST(I, POS)¶

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

Parameters

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

Returns

The return value is of type LOGICAL

Standard:: Fortran 90 and later, has overloads that are GNU extensions
Class:: Elemental function

Syntax:

RESULT = BTEST(I, POS)

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`	Fortran 95 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