ibits

Date:: 10-12-2011

NAME

IBITS, IIBITS, JIBITS, KIBITS - Extract a sequence of bits

SYNOPSIS

IBITS ([I=]i [,POS=]pos [,LEN=]len)
IIBITS ([I=]i [,POS=]pos [,LEN=]len)
JIBITS ([I=]i [,POS=]pos [,LEN=]len)
KIBITS ([I=]i [,POS=]pos [,LEN=]len)

IMPLEMENTATION

Cray Linux Environment (CLE)

STANDARDS

Fortran

Fortran extensions: IIBITS, JIBITS, KIBITS

DESCRIPTION

The IBITS, IIBITS, JIBITS, and KIBITS intrinsic functions extract a sequence of bits. They accept the following arguments:

i: Must be of type integer. For IIBITS, must be of type integer (KIND=2). For JIBITS, must be of type integer (KIND=4). For KIBITS, must be of type integer (KIND=8).
pos: Must be of type integer. It must be nonnegative and pos + len must be less than or equal to BIT_SIZE (i).
len: Must be of type integer and nonnegative.

These are elemental intrinsic functions. The names of these intrinsics cannot be passed as arguments.

RETURN VALUES

The result type and type parameter are the same as i. The result has the value of the sequence of len bits in i beginning at bit pos right adjusted and with all other bits zero.

The bit model defines the model for the interpretation of an integer value as a sequence of bits. For more information on the bit model, see the models(3i) man page.

EXAMPLES

IBITS(14,1,3) yields 7. In this example, the bits are numbered from right to left, so they are extracted from right to left.