Add links to make the math docs more usable.

This commit is contained in:
Raymond Hettinger 2011-03-31 12:06:47 -07:00
commit 6604662616
1 changed files with 23 additions and 7 deletions

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@ -156,10 +156,10 @@ Power and logarithmic functions
.. function:: expm1(x) .. function:: expm1(x)
Return ``e**x - 1``. For small floats *x*, the subtraction in Return ``e**x - 1``. For small floats *x*, the subtraction in ``exp(x) - 1``
``exp(x) - 1`` can result in a significant loss of precision; the can result in a `significant loss of precision
:func:`expm1` function provides a way to compute this quantity to <http://en.wikipedia.org/wiki/Loss_of_significance>`_\; the :func:`expm1`
full precision:: function provides a way to compute this quantity to full precision::
>>> from math import exp, expm1 >>> from math import exp, expm1
>>> exp(1e-5) - 1 # gives result accurate to 11 places >>> exp(1e-5) - 1 # gives result accurate to 11 places
@ -269,6 +269,9 @@ Angular conversion
Hyperbolic functions Hyperbolic functions
-------------------- --------------------
`Hyperbolic functions <http://en.wikipedia.org/wiki/Hyperbolic_function>`_
are analogs of trigonometric functions that are based on hyperbolas
instead of circles.
.. function:: acosh(x) .. function:: acosh(x)
@ -305,21 +308,34 @@ Special functions
.. function:: erf(x) .. function:: erf(x)
Return the error function at *x*. Return the `error function <http://en.wikipedia.org/wiki/Error_function>`_ at
*x*.
The :func:`erf` function can be used to compute traditional statistical
functions such as the `cumulative standard normal distribution
<http://en.wikipedia.org/wiki/Normal_distribution#Cumulative_distribution_function>`_::
def phi(x):
'Cumulative distribution function for the standard normal distribution'
return (1.0 + erf(x / sqrt(2.0))) / 2.0
.. versionadded:: 3.2 .. versionadded:: 3.2
.. function:: erfc(x) .. function:: erfc(x)
Return the complementary error function at *x*. Return the complementary error function at *x*. The `complementary error
function <http://en.wikipedia.org/wiki/Error_function>`_ is defined as
``1.0 - erf(x)``. It is used for large values of *x* where a straight
substraction from *1* would cause a `loss of significance
<http://en.wikipedia.org/wiki/Loss_of_significance>`_\.
.. versionadded:: 3.2 .. versionadded:: 3.2
.. function:: gamma(x) .. function:: gamma(x)
Return the Gamma function at *x*. Return the `Gamma function<http://en.wikipedia.org/wiki/Gamma_function>` at *x*.
.. versionadded:: 3.2 .. versionadded:: 3.2