GNU Scientific Library Reference Manual - Third Edition (v1.12)by M. Galassi, J. Davies, J. Theiler, B. Gough, G. Jungman, P. Alken, M. Booth, F. Rossi Paperback (6"x9"), 592 pages, 60 figures ISBN 0954612078 RRP £24.95 ($39.95) |

## 4.1 Mathematical Constants

The library ensures that the standard bsd mathematical constants are defined. For reference, here is a list of the constants:

`M_E`

- The base of exponentials, e
`M_LOG2E`

- The base-2 logarithm of e, \log_2 (e)
`M_LOG10E`

- The base-10 logarithm of e, \log_10 (e)
`M_SQRT2`

- The square root of two, \sqrt 2
`M_SQRT1_2`

- The square root of one-half, \sqrt{1/2}
`M_SQRT3`

- The square root of three, \sqrt 3
`M_PI`

- The constant pi, \pi
`M_PI_2`

- Pi divided by two, \pi/2
`M_PI_4`

- Pi divided by four, \pi/4
`M_SQRTPI`

- The square root of pi, \sqrt\pi
`M_2_SQRTPI`

- Two divided by the square root of pi, 2/\sqrt\pi
`M_1_PI`

- The reciprocal of pi, 1/\pi
`M_2_PI`

- Twice the reciprocal of pi, 2/\pi
`M_LN10`

- The natural logarithm of ten, \ln(10)
`M_LN2`

- The natural logarithm of two, \ln(2)
`M_LNPI`

- The natural logarithm of pi, \ln(\pi)
`M_EULER`

- Euler's constant, \gamma

ISBN 0954612078 | GNU Scientific Library Reference Manual - Third Edition (v1.12) | See the print edition |