Arbitrary Precision Arithmetic (The GNU Awk User’s Guide)

16 Arithmetic and Arbitrary-Precision Arithmetic with gawk

This chapter introduces some basic concepts relating to how computers do arithmetic and defines some important terms. It then proceeds to describe floating-point arithmetic, which is what awk uses for all its computations, including a discussion of arbitrary-precision floating-point arithmetic, which is a feature available only in gawk. It continues on to present arbitrary-precision integers, and concludes with a description of some points where gawk and the POSIX standard are not quite in agreement.

NOTE: Most users of gawk can safely skip this chapter. But if you want to do scientific calculations with gawk, this is the place to be.

• Computer Arithmetic		A quick intro to computer math.
• Math Definitions		Defining terms used.
• MPFR features		The MPFR features in `gawk`.
• FP Math Caution		Things to know.
• Arbitrary Precision Integers		Arbitrary Precision Integer Arithmetic with `gawk`.
• Checking for MPFR		How to check if MPFR is available.
• POSIX Floating Point Problems		Standards Versus Existing Practice.
• Floating point summary		Summary of floating point discussion.