`mixOnekn' is used for the estimation of the following two-component mixture model:
$$h(x;\boldsymbol{\theta},f) = \pi f(x-\mu_1)+(1-\pi)f(x-\mu_2),$$
where \(\boldsymbol{\theta}=(\pi,\mu_1,\mu_2)^{\top}\) is the parameter to estimate,
\(f\) is an unknown density function that is symmetric at zero.
The parameters are estimated by assuming \(f\) is the normal density and the
first component has a mean of 0.
This function can be used to obtain initial values for the mixMPHD
function.