SimPEG.maps.ExpMap.deriv#
- ExpMap.deriv(m, v=None)[source]#
- Derivative of mapping with respect to the input parameters. - For a mapping \(\mathbf{u}(\mathbf{m})\) that computes the natural exponential function for each parameter in the model \(\mathbf{m}\), i.e.: \[\mathbf{u}(\mathbf{m}) = exp(\mathbf{m}),\]- the derivative of the mapping with respect to the model is a diagonal matrix of the form: \[\frac{\partial \mathbf{u}}{\partial \mathbf{m}} = \textrm{diag} \big ( exp(\mathbf{m}) \big )\]- Parameters
- m(nP)numpy.ndarray
- A vector representing a set of model parameters 
- v(nP)numpy.ndarray
- If not - None, the method returns the derivative times the vector v
 
- m(
- Returns
- scipy.sparse.csr_matrix
- Derivative of the mapping with respect to the model parameters. If the input argument v is not - None, the method returns the derivative times the vector v.