This option defines the maximum allowable relative error, measured in ulps,
for math library function results.
This option can affect run-time performance and the accuracy of results.
If you need to define the accuracy for a math function of a certain
precision, specify the function name of the precision that you need. For
example, if you want double precision, you can specify :sin; if you want single
precision, you can specify :sinf, as in
If you do not specify any function names, then the setting applies to all
functions (and to all precisions). However, as soon as you specify an
individual function name, the setting applies only to the function of
corresponding precision. So, for example, sinf applies only to the
single-precision sine function, sin applies only to the double-precision sine
function, sinl applies only to the extended-precision sine function, etc.
There are three options you can use to express the maximum relative error.
They are as follows:
If more than one of these options are specified, the default value for the
maximum relative error is determined by the last one specified on the command
If none of the above options are specified, the default values for the
maximum relative error are determined by the setting of the following options:
Many routines in libraries LIBM (Math Library) and SVML (Short Vector Math
Library) are more highly optimized for Intel® microprocessors than for
Product and Performance Information
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