smash.generate_mesh#

smash.generate_mesh(path, bbox=None, x=None, y=None, area=None, code=None, max_depth=1, epsg=None)[source]#

Automatic mesh generation.

Hint

See the User Guide for more.

Parameters:
pathstr

Path to the flow directions file. The file will be opened with gdal.

bboxsequence or None, default None

Bounding box with the following convention:

(xmin, xmax, ymin, ymax). The bounding box values must respect the CRS of the flow directions file.

Note

If not given, x, y and area must be filled in.

xfloat, sequence or None, default None

The x-coordinate(s) of the catchment outlet(s) to mesh. The x value(s) must respect the CRS of the flow directions file. The x size must be equal to y and area.

yfloat, sequence or None, default None

The y-coordinate(s) of the catchment outlet(s) to mesh. The y value(s) must respect the CRS of the flow directions file. The y size must be equal to x and area.

areafloat, sequence or None, default None

The area of the catchment(s) to mesh in m². The area size must be equal to x and y.

codestr, sequence or None, default None

The code of the catchment(s) to mesh. The code size must be equal to x, y and area. In case of bouding box meshing, the code argument is not used.

Note

If not given, the default code is:

['_c0', '_c1', ..., '_cn-1'] with \(n\), the number of gauges.

max_depthint, default 1

The maximum depth accepted by the algorithm to find the catchment outlet. A max_depth of 1 means that the algorithm will search among the 2-length combinations in:

(row - 1, row, row + 1, col - 1, col, col + 1), the coordinates that minimize the relative error between the given catchment area and the modeled catchment area calculated from the flow directions file. This can be generalized to \(n\).

../../_images/max_depth.png
epsgstr, int or None, default None

The EPSG value of the flow directions file. By default, if the projection is well defined in the flow directions file. It is not necessary to provide the value of the EPSG. On the other hand, if the projection is not well defined in the flow directions file (i.e. in ASCII file). The epsg argument must be filled in.

Returns:
dict

A mesh dictionary that can be used to initialize the Model object.

See also

Model

Primary data structure of the hydrological model smash.

Examples

>>> flwdir = smash.load_dataset("flwdir")
>>> mesh = smash.generate_mesh(
... flwdir,
... x=[840_261, 826_553, 828_269],
... y=[6_457_807, 6_467_115, 6_469_198],
... area=[381.7 * 1e6, 107 * 1e6, 25.3 * 1e6],
... code=["V3524010", "V3515010", "V3517010"],
... )
>>> mesh.keys()
dict_keys(['dx', 'nrow', 'ncol', 'ng', 'nac', 'xmin', 'ymax',
           'flwdir', 'flwdst', 'flwacc', 'path', 'gauge_pos',
           'code', 'area', 'active_cell'])