simpeg.electromagnetics.time_domain.Simulation3DMagneticField.getAsubdiag#
- Simulation3DMagneticField.getAsubdiag(tInd)[source]#
Sub-diagonal system matrix for the time-step index provided.
This method returns the sub-diagonal system matrix for the time-step index provided:
\[\mathbf{B}_k = -\frac{1}{\Delta t_k} \mathbf{M_{e\mu}}\]where \(\Delta t_k\) is the step-length and \(\mathbf{M_{e \mu}}\) is the permeability inner-product matrix on edges.
See the Notes section of the doc strings for
Simulation3DMagneticFieldfor a full description of the formulation.- Parameters:
- tInd
int The time-step index; between
[0, n_steps-1].
- tInd
- Returns:
- (
n_edges,n_edges)sp.sparse.csr_matrix The sub-diagonal system matrix.
- (