Measured Accuracy of VML Functions

  Default processor Intel® Pentium® III processor Intel® Pentium® 4 processor Intel® Pentium® 4 processor with Streaming SIMD Extensions 3 Intel® Itanium® 2 processor
float double float double float double float double float double
HA LA HA LA HA LA HA LA HA LA HA LA HA LA HA LA HA LA HA LA
Inv

0.5000

0.5000

0.5000

0.5000

0.4990

0.4990

0.5000

0.5000

0.4990

3.1000

0.5000

2.4700

0.4990

3.1000

0.5000

2.4700

0.5000

0.5000

0.5000

0.5000

Div

0.5000

0.5000

0.4990

0.4990

0.5000

0.5000

0.4990

0.4990

0.5000

3.5200

0.4990

0.4990

0.5000

3.5200

0.4990

0.4990

0.5000

0.5000

0.5000

0.5000

Sqrt

0.7294

0.7294

0.7028

0.7028

0.7294

0.7294

0.7028

0.7028

0.7294

3.1565

0.5003

1.8467

0.5041

2.5700

0.5003

1.4100

0.5000

0.5000

0.5000

0.5000

InvSqrt

0.9103

0.9103

0.7811

0.7811

0.9103

0.9103

0.7811

0.7811

0.9103

3.9613

0.5000

0.9764

0.9103

3.2500

0.5000

0.9690

0.5000

0.5000

0.5002

0.5002

Cbrt

0.5818

0.5818

0.6853

0.6853

0.5818

0.5818

0.6853

0.6853

0.9081

2.0242

0.5150

1.9600

0.9081

1.7600

0.5150

1.9600

0.5075

0.5075

0.5016

0.5016

InvCbrt

0.7930

0.7690

0.5700

0.5800

0.7830

0.8040

0.5700

0.5990

0.8550

0.9740

0.5110

2.1700

0.8550

0.9740

0.5110

2.1700

0.5010

0.5000

0.5000

0.5000

Pow

0.5000

2.4638

0.5270

1.4728

0.5000

2.4638

0.5910

1.4728

0.5576

0.5576

0.5200

2.5033

0.5576

0.5576

0.5200

1.8700

0.5084

0.5084

0.5002

0.5002

Powx

0.4990

0.4990

0.7080

0.8040

0.4990

0.4990

0.5650

0.6100

0.5250

0.5440

0.5050

0.5250

0.5250

0.5440

0.5050

0.5250

0.5000

0.4990

0.4980

0.5000

Exp

0.6103

0.6103

0.7872

0.7872

0.6103

0.6103

0.7872

0.7872

1.0000

1.9300

0.7418

3.5105

1.0000

1.6100

0.7418

2.3900

1.0000

1.0000

0.5216

0.5216

Ln

0.7197

0.7197

0.6712

0.6712

0.7197

0.7197

0.6712

0.6712

0.5301

1.1417

0.5665

3.0375

0.5301

0.5301

0.5665

0.5665

0.5123

0.5123

0.5113

0.5113

Log10

0.6984

0.6984

0.9289

0.9289

0.6984

0.6984

0.9289

0.9289

0.7434

1.7048

0.5687

3.7011

0.7434

0.7434

0.5687

0.5687

0.5110

0.5110

0.5110

0.5110

Cos

0.8010

2.6102

0.9151

0.9151

0.8010

2.6102

0.9151

0.9151

0.8010

2.2860

0.5131

0.5131

0.8010

1.4900

0.5280

0.5280

0.5003

0.5003

0.5067

0.5067

Sin

0.8010

2.2491

0.9150

0.9150

0.8010

2.2491

0.9150

0.9150

0.8010

2.3455

0.5138

0.5138

0.8010

1.4100

0.5367

0.5367

0.5003

0.5003

0.5061

0.5061

SinCos

0.5621

1.3372

0.8201

0.8510

0.5621

1.3372

0.8201

0.8201

0.5621

1.7301

0.5187

1.7465

0.5621

1.4800

0.5367

1.2700

0.5017

0.5017

0.5005

0.5005

Tan

0.9352

2.8962

0.9735

2.1796

0.9352

2.8962

0.9735

2.1796

0.9352

2.8962

0.9735

3.4178

0.9352

2.3100

0.9735

2.9900

0.5006

0.5006

0.5012

0.5012

Acos

0.7873

2.5080

0.6415

0.6415

0.7873

2.5080

0.6415

0.6415

0.7780

2.5080

0.7680

3.1840

0.7780

2.3300

0.7680

3.1100

0.5041

0.5041

0.5083

0.5083

Asin

0.9245

2.2669

0.6504

0.6504

0.9245

2.2669

0.6504

0.6504

0.8255

2.2669

0.8140

2.1268

0.8255

1.9200

0.8140

1.8900

0.5045

0.5045

0.5108

0.5108

Atan

0.8595

3.6805

0.8454

0.8454

0.8595

3.6805

0.8454

0.8454

0.8595

3.6805

0.8454

3.7524

0.8595

2.4300

0.8454

2.0800

0.5026

0.5026

0.5015

0.5015

Atan2

0.9528

3.8685

0.5773

0.5773

0.9528

3.8685

0.5773

0.5773

0.7961

3.0752

0.7448

3.9960

0.7961

2.9100

0.7448

3.2000

0.5030

0.5030

0.5015

0.5015

Cosh

0.6103

0.6103

0.8124

0.8124

0.6103

0.6103

0.8124

0.8124

0.7497

2.2114

0.7567

4.0363

0.7497

1.5200

0.7567

3.1900

0.5000

0.5000

0.5013

0.5013

Sinh

0.5000

0.5000

0.8884

0.8884

0.5000

0.5000

0.8884

0.8884

0.5039

3.5462

0.7659

3.2407

0.5039

1.7600

0.7659

1.0600

0.5074

0.5074

0.5114

0.5114

Tanh

0.7611

0.7611

0.8777

0.8777

0.7611

0.7611

0.8777

0.8777

0.5051

1.0159

0.5293

1.3478

0.5051

0.8010

0.7442

1.1900

0.5061

0.5061

0.5012

0.5012

Acosh

0.8753

0.8753

0.7507

0.7507

0.8753

0.8753

0.7507

0.7507

0.8753

3.0721

0.7507

3.0000

0.8753

1.7700

0.7507

2.4100

0.5112

0.5112

0.5220

0.5113

Asinh

0.8753

0.8753

0.8067

0.8067

0.8753

0.8753

0.8067

0.8067

0.8753

3.3657

0.8067

2.0193

0.8753

2.9700

0.8067

1.4600

0.5129

0.5129

0.5167

0.5167

Atanh

0.8305

0.8305

0.7484

0.7484

0.8305

0.8305

0.7484

0.7484

0.8245

2.7015

0.6508

3.1548

0.8245

1.7700

0.6508

2.0600

0.5113

0.5113

0.5214

0.5214

Erf

0.5000

0.5000

0.5012

0.5012

0.5000

0.5000

0.5012

0.5012

0.5079

1.4608

0.6220

1.3254

0.5079

1.4200

0.7944

1.1000

0.5124

0.5124

0.5028

0.5028

Erfc

0.5000

0.5000

0.5006

0.5006

0.5000

0.5000

0.5006

0.5006

0.5240

1.9229

0.5357

2.5685

0.5240

1.8900

0.5357

2.1700

0.5340

0.5340

0.5275

0.5275


Notes:
1) Units - ULP (Units in The Last Place)
2) 0 means X87 code for all IA-32 processors

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