Function Exp

The Exp function computes an exponential.

Performance:

  Default processor Intel® Pentium® III processor Intel® Pentium® 4 processor Intel® Pentium® 4 processor with Streaming SIMD Extensions 3 (SSE3) Intel® Itanium® 2 processor
vsExp (HA version) 23.57 19.73 11.16 11.82 6.19
vdExp (HA version) 37.82 38.34 26.12 28.50 6.50
Notes:
1) Units - CPE (Clocks per Element)
2) Performance was measured on "working" interval (double precision: [-1,1]; single precision: [-1,1] )
3) Data - vectors of 1000 elements with random generated numbers
4) "Default" means X87 code for all IA-32 processors
5) Performance of "default" version was measured on Intel® Pentium® III processor

 
Notes:
1) *           X87 code for all processors
2) **         Intel® Pentium® III processor
3) ***       Intel® Pentium® 4 processor
4) ****     Intel® Pentium® 4 processor with Streaming SIMD Extensions 3 (SSE3)
5) *****   Intel® Itanium® 2 processor
6) Logarithmic scale is used for "Vectors Size" axis

Maximal observed error for the whole function domain:

  Default processor Pentium III processor Pentium 4 processor Pentium 4 processor with SSE3 Itanium 2 processor
vsExp (HA version) 0.6103 0.6103 1.0000 1.0000 1.0000
vdExp (HA version) 0.7872 0.7872 0.7418 0.7418 0.5216
Notes:
1) Units - ULP (Units in The Last Place)

Special values:

Function Input Argument Result Default processor Pentium III processor Pentium 4 processor Pentium 4 processor with SSE3 Itanium 2 processor
vsExp/vdExp
(HA version)
0 1 + + + + +
NaN (Both QNaN and SNaN) NaN (Raise Invalid Exeption for SNaN) + + + + +
x> Precision`s Overflow Threshold Inf (Raise Overflow Exeption) + + + + +

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