Reading and writing HDF5 mesh files

A Layermesh mesh object can be written to an HDF5 file using its write() method, which takes a filename as its parameter, e.g.:

msh.write('mymesh.h5')

writes the mesh object msh to the file “mymesh.h5”.

Similarly, a mesh object can be read in from file by passing in a filename when creating it:

import layermesh.mesh as lm
msh = lm.mesh('mymesh.h5')

creates a new mesh object called msh and reads its contents from the file “mymesh.h5”.

Layermesh HDF5 files have a simple structure with four groups:

• cell: one integer scalar type_sort dataset containing the value of the mesh cell_type_sort property

• layer: one rank-1 array float elevation dataset containing, in order, the top property of each mesh layer, and finally the bottom property of the last (bottom) layer

• node: one rank-2 array float position dataset containing the pos property of each node (horizontal position) in the mesh node list

• column: an rank-2 integer node dataset containing the index of each node in the column, for each column in the mesh column list (columns with fewer nodes padded out with -1 values) ; a rank-1 integer num_layers dataset containing the number of layers for each column; and also an optional rank-1 integer bottom_layer dataset containing the index of the bottom layer for each column (assumed -1 if not present)