DiscreteLineSegmentInterface

This interface is used to define mesh along a line segment in 3D space. The line segment is defined with a "start" point xstart\mathbf{x}_\text{start}, corresponding to either end, the direction d\mathbf{d} to the other end, and the distance in that direction, LL. Thus the other end of the line segment is

xend=xstart+Ld\eqp\mathbf{x}_\text{end} = \mathbf{x}_\text{start} + L \mathbf{d} \eqp

These quantities are defined using the following parameters:

  • position: the "start" point xstart\mathbf{x}_\text{start},

  • orientation: the direction d\mathbf{d} (which gets automatically normalized), and

  • length: the length(s) that sum to LL.

The most basic mesh specification is given by a single value for the parameters length and n_elems, which correspond to the length of the component and number of uniformly-sized elements to use. For example, the following parameters would specify a total length L=50L = 50 m, divided into 100 elements (each with width 0.5 m):

length = 50
n_elems = 100

The length and n_elems parameters can also be supplied with multiple values. Multiple values correspond to splitting the length into segments that can have different element sizes. However, within each segment, the discretization is assumed uniform. The numbers of elements in each segment are specified with the parameter n_elems, with entries corresponding to the entries in length. For example, the following would also specify a total length L=50L = 50 m with 100 total elements, but in this case the first 10 m have 40 elements of size 0.25 m, whereas the last 40 m have 60 elements of size 0.6ˉ0.\bar{6} m.

length = '10 40'
n_elems = '40 60'