Subnormal: Difference between revisions

From Citizendium
Jump to navigation Jump to search
imported>Niek Sanders
(Initial content.)
 
imported>Joe Quick
m (subpages)
 
Line 1: Line 1:
{{subpages}}
'''Subnormal''' [[floating point]] values (also known as '''denormal''') are too small to be normalized yet can still be represented [http://www.intel.com/software/products/compilers/docs/fmac/doc_files/source/extfile/fpops_for/common/fpops_denormal_num.htm].  Depending on the specific computation, they may provide additional, useful precision.  However, managing these values typically causes major slowdowns in a [[Central processing unit|CPU]]'s [[floating point unit]] [http://www.intel.com/software/products/documentation/vlin/mergedprojects/analyzer_ec/mergedprojects/reference_olh/pentium4_hh/advice4_hh/found_x87_denormal_numbers_.htm].   
'''Subnormal''' [[floating point]] values (also known as '''denormal''') are too small to be normalized yet can still be represented [http://www.intel.com/software/products/compilers/docs/fmac/doc_files/source/extfile/fpops_for/common/fpops_denormal_num.htm].  Depending on the specific computation, they may provide additional, useful precision.  However, managing these values typically causes major slowdowns in a [[Central processing unit|CPU]]'s [[floating point unit]] [http://www.intel.com/software/products/documentation/vlin/mergedprojects/analyzer_ec/mergedprojects/reference_olh/pentium4_hh/advice4_hh/found_x87_denormal_numbers_.htm].   


Line 4: Line 5:


For some CPU architectures, it is possible to control the treatment of subnormals.  For instance, these values can automatically be rounded to zero.
For some CPU architectures, it is possible to control the treatment of subnormals.  For instance, these values can automatically be rounded to zero.
[[Category:Computers Workgroup]]

Latest revision as of 20:04, 20 December 2007

This article is a stub and thus not approved.
Main Article
Discussion
Definition [?]
Related Articles  [?]
Bibliography  [?]
External Links  [?]
Citable Version  [?]
 
This editable Main Article is under development and subject to a disclaimer.

Subnormal floating point values (also known as denormal) are too small to be normalized yet can still be represented [1]. Depending on the specific computation, they may provide additional, useful precision. However, managing these values typically causes major slowdowns in a CPU's floating point unit [2].

For the Intel x86 architecture, floats between 1.17549429E-38 and 1.40129846E-45 are denormalized while for doubles the range is 2.2250738585072008D-308 and 4.94065645841246544D-324. [3]

For some CPU architectures, it is possible to control the treatment of subnormals. For instance, these values can automatically be rounded to zero.