pc, Qpc

Enables control of floating-point significand precision.

IDE Equivalent

None

Architectures

IA-32, Intel® 64 architectures

Syntax

Linux and Mac OS X:

-pcn

Windows:

/Qpcn

Arguments

n

Is the floating-point significand precision. Possible values are:

32	Rounds the significand to 24 bits (single precision).
64	Rounds the significand to 53 bits (double precision).
80	Rounds the significand to 64 bits (extended precision).

Default

-pc80
or/Qpc64

On Linux* and Mac OS* X systems, the floating-point significand is rounded to 64 bits. On Windows* systems, the floating-point significand is rounded to 53 bits.

Description

This option enables control of floating-point significand precision.

Some floating-point algorithms are sensitive to the accuracy of the significand, or fractional part of the floating-point value. For example, iterative operations like division and finding the square root can run faster if you lower the precision with the this option.

Note that a change of the default precision control or rounding mode, for example, by using the -pc32 (Linux and Mac OS X) or /Qpc32 (Windows) option or by user intervention, may affect the results returned by some of the mathematical functions.

Alternate Options