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), then m * n * k samples are drawn.

Returns:

outndarray

Drawn samples from the parameterized exponential distribution.

Restriction

• If scale is neither a scalar nor None : NotImplementedError occurs.