get_hx¶
-
emg3d.meshes.
get_hx
(alpha, domain, nx, x0, resp_domain=True)[source]¶ Return cell widths for given input.
Find the number of cells left and right of x0, nl and nr respectively, for the provided alpha. For this, we solve
\[\frac{x_\text{max}-x_0}{x_0-x_\text{min}} = \frac{a^{nr}-1}{a^{nl}-1}\]where \(a = 1+\alpha\).
Parameters: - alpha : float
Stretching factor a is given by
a=1+alpha
.- domain : list
[start, end] of model domain.
- nx : int
Number of cells.
- x0 : float
Center of the grid. x0 is restricted to domain.
- resp_domain : bool
If False (default), then the domain-end might shift slightly to assure that the same stretching factor is applied throughout. If set to True, however, the domain is respected absolutely. This will introduce one stretch-factor which is different from the other stretch factors, to accommodate the restriction. This one-off factor is between the left- and right-side of x0, or, if x1 is provided, just after x1.
Returns: - hx : ndarray
Cell widths of mesh.