ieee

Arguments

mod

integer scalar whose possible values are 0, 1 or 2

Description

ieee() returns the current floating point exception mode.

0

floating point exception produces an error.

%inf and %nan special values can be used in this mode without error. For instance, %inf/%inf, %inf-%inf or %inf/%nan are known operations.

1

floating point exception produces a warning.

2

floating point exception produces Inf or Nan.

ieee(mod) sets the current floating point exception mode to mod.

The default initial mode is 2. This default value may be set in any of the following ways: Through the Preferences GUI: preferences, in the section General => Environment => ieee. Equivalently, using xmlSetValues as follows (to set the mode to 1) : xmlSetValues("//general/body/environment", ["fpe";"1"]) Or by using ieee(mod) in your startup file.

Floating point exception arising inside some library algorithms are not yet handled by ieee modes.

Examples

ieee(1); 1/0
ieee(2); 1/0, log(0)

See Also

• %nan — not-a-number
• %inf — infinity
• isinf — tests for infinite elements
• isnan — check for "Not a Number" entries
• number_properties — determine floating-point parameters

History