nlcpy.random.RandomState.exponential¶
-
RandomState.
exponential
(self, scale=1.0, size=None)¶ Draws samples from an exponential distribution.
Its probability density function is
\[f(x; \frac{1}{\beta}) = \frac{1}{\beta} \exp(-\frac{x}{\beta}),\]for
x > 0
and 0 elsewhere. \(\beta\) is the scale parameter, which is the inverse of the rate parameter \(\lambda = 1/\beta\).- Parameters
- scalefloat
The scale parameter, \(\beta = 1/\lambda\). Must be non-negative.
- sizeint or tuple of ints, optional
Output shape. If the given shape is, e.g.,
(m, n, k)
, thenm * n * k
samples are drawn.
- Returns
- outndarray
Drawn samples from the parameterized exponential distribution.
制限事項
If scale is neither a scalar nor None : NotImplementedError occurs.