scipy.special.betaln#
- scipy.special.betaln(a, b, out=None) = <ufunc 'betaln'>#
- Natural logarithm of absolute value of beta function. - Computes - ln(abs(beta(a, b))).- Parameters:
- a, barray_like
- Positive, real-valued parameters 
- outndarray, optional
- Optional output array for function values 
 
- Returns:
- scalar or ndarray
- Value of the betaln function 
 
 - See also - Examples - >>> import numpy as np >>> from scipy.special import betaln, beta - Verify that, for moderate values of - aand- b,- betaln(a, b)is the same as- log(beta(a, b)):- >>> betaln(3, 4) -4.0943445622221 - >>> np.log(beta(3, 4)) -4.0943445622221 - In the following - beta(a, b)underflows to 0, so we can’t compute the logarithm of the actual value.- >>> a = 400 >>> b = 900 >>> beta(a, b) 0.0 - We can compute the logarithm of - beta(a, b)by using- betaln:- >>> betaln(a, b) -804.3069951764146