lognorm_ex

class lognorm_ex(mean=1.0, std=1.0, **kwargs)

Bases: Dist

Lognormal distribution, parameterized in terms of the “explicit” (lognormal) distribution, with mean=mean and std=std for this distribution (see lognorm_im for comparison). Note that a mean ≤ 0.0 is impossible, since this is the parameter of the distribution after the log transform.

Parameters:

• mean (float) – the mean of this distribution (not the underlying distribution) (default 1.0)

• std (float) – the standard deviation of this distribution (not the underlying distribution) (default 1.0)

Example:

ss.lognorm_ex(mean=2, std=1, strict=False).rvs(1000).mean() # Should be close to 2

Attributes

bitgen
state	Get the current state
state_int	Get the integer corresponding to the current state

Methods

convert_ex_to_im()

Lognormal distributions can be specified in terms of the mean and standard deviation of the “explicit” lognormal distribution, or the “implicit” normal distribution. This function converts the parameters from the lognormal distribution to the parameters of the underlying (implicit) distribution, which are the form expected by NumPy’s and SciPy’s lognorm() distributions.

sync_pars()

Convert from overlying to underlying parameters, then translate to SciPy