summaryrefslogtreecommitdiff
path: root/numpy/oldnumeric/rng.py
diff options
context:
space:
mode:
Diffstat (limited to 'numpy/oldnumeric/rng.py')
-rw-r--r--numpy/oldnumeric/rng.py137
1 files changed, 0 insertions, 137 deletions
diff --git a/numpy/oldnumeric/rng.py b/numpy/oldnumeric/rng.py
deleted file mode 100644
index 06120798d..000000000
--- a/numpy/oldnumeric/rng.py
+++ /dev/null
@@ -1,137 +0,0 @@
-"""Re-create the RNG interface from Numeric.
-
-Replace import RNG with import numpy.oldnumeric.rng as RNG.
-It is for backwards compatibility only.
-
-"""
-from __future__ import division, absolute_import, print_function
-
-__all__ = ['CreateGenerator', 'ExponentialDistribution', 'LogNormalDistribution',
- 'NormalDistribution', 'UniformDistribution', 'error', 'ranf',
- 'default_distribution', 'random_sample', 'standard_generator']
-
-import numpy.random.mtrand as mt
-import math
-
-class error(Exception):
- pass
-
-class Distribution(object):
- def __init__(self, meth, *args):
- self._meth = meth
- self._args = args
-
- def density(self, x):
- raise NotImplementedError
-
- def __call__(self, x):
- return self.density(x)
-
- def _onesample(self, rng):
- return getattr(rng, self._meth)(*self._args)
-
- def _sample(self, rng, n):
- kwds = {'size' : n}
- return getattr(rng, self._meth)(*self._args, **kwds)
-
-
-class ExponentialDistribution(Distribution):
- def __init__(self, lambda_):
- if (lambda_ <= 0):
- raise error("parameter must be positive")
- Distribution.__init__(self, 'exponential', lambda_)
-
- def density(x):
- if x < 0:
- return 0.0
- else:
- lambda_ = self._args[0]
- return lambda_*math.exp(-lambda_*x)
-
-class LogNormalDistribution(Distribution):
- def __init__(self, m, s):
- m = float(m)
- s = float(s)
- if (s <= 0):
- raise error("standard deviation must be positive")
- Distribution.__init__(self, 'lognormal', m, s)
- sn = math.log(1.0+s*s/(m*m));
- self._mn = math.log(m)-0.5*sn
- self._sn = math.sqrt(sn)
- self._fac = 1.0/math.sqrt(2*math.pi)/self._sn
-
- def density(x):
- m, s = self._args
- y = (math.log(x)-self._mn)/self._sn
- return self._fac*math.exp(-0.5*y*y)/x
-
-
-class NormalDistribution(Distribution):
- def __init__(self, m, s):
- m = float(m)
- s = float(s)
- if (s <= 0):
- raise error("standard deviation must be positive")
- Distribution.__init__(self, 'normal', m, s)
- self._fac = 1.0/math.sqrt(2*math.pi)/s
-
- def density(x):
- m, s = self._args
- y = (x-m)/s
- return self._fac*math.exp(-0.5*y*y)
-
-class UniformDistribution(Distribution):
- def __init__(self, a, b):
- a = float(a)
- b = float(b)
- width = b-a
- if (width <=0):
- raise error("width of uniform distribution must be > 0")
- Distribution.__init__(self, 'uniform', a, b)
- self._fac = 1.0/width
-
- def density(x):
- a, b = self._args
- if (x < a) or (x >= b):
- return 0.0
- else:
- return self._fac
-
-default_distribution = UniformDistribution(0.0, 1.0)
-
-class CreateGenerator(object):
- def __init__(self, seed, dist=None):
- if seed <= 0:
- self._rng = mt.RandomState()
- elif seed > 0:
- self._rng = mt.RandomState(seed)
- if dist is None:
- dist = default_distribution
- if not isinstance(dist, Distribution):
- raise error("Not a distribution object")
- self._dist = dist
-
- def ranf(self):
- return self._dist._onesample(self._rng)
-
- def sample(self, n):
- return self._dist._sample(self._rng, n)
-
-
-standard_generator = CreateGenerator(-1)
-
-def ranf():
- "ranf() = a random number from the standard generator."
- return standard_generator.ranf()
-
-def random_sample(*n):
- """random_sample(n) = array of n random numbers;
-
- random_sample(n1, n2, ...)= random array of shape (n1, n2, ..)"""
-
- if not n:
- return standard_generator.ranf()
- m = 1
- for i in n:
- m = m * i
- return standard_generator.sample(m).reshape(*n)