Calculate the negative log-likelihood given Weibull mixture proportions and parameters

Given the input vector x and Weibull mixture proportions and parameters z and theta, calculate the negative log-likelihood.

calcNegLogLikWeibMix(theta, x, z)

Arguments

theta	The value of shape and scale parameters with the ordering [sh1,sc1,sh2,sc2,...]
x	Locations at which to evaluate negative log-likelihood
z	Vector of mixture proportions

The negative log-likelihood (summed)