Interaction WolfArray/vectors

from wolfhece import __version__
assert __version__ > "2.2.7", "Please update wolfhece to 2.2.7 or later - you have " + __version__

from wolfhece.wolf_array import WolfArray, header_wolf
from wolfhece.PyVertexvectors import Zones, zone, vector

import numpy as np

Creation of an array

h = header_wolf()
h.shape = (100, 100)
h.set_resolution(1., 1.)

a = WolfArray(srcheader=h)

Creation of a vector

Square 5m x 5m and 1 attached value named ‘testvalue’.

v = vector(fromnumpy= np.asarray([[5.,5.],
                                  [10.,5.],
                                  [10.,10.],
                                  [5.,10.]]))

v.close_force()

v.add_value('testvalue', 5.)

Rasterizing

a bit like RasterIO <https://rasterio.readthedocs.io/en/stable/api/rasterio.rio.rasterize.html#rio-rasterize>_

a.rasterize_vector_valuebyid(v, 'testvalue')

a.plot_matplotlib()

(<Figure size 640x480 with 1 Axes>, <Axes: >)

Creation of a zone

z = zone()

v2 = vector(fromnumpy= np.asarray([[25.,25.],
                                  [30.,25.],
                                  [50.,35.],
                                  [15.,30.]]))
v2.close_force()

z.add_vector(v, forceparent=True)
z.add_vector(v2, forceparent=True)

z.add_values('testvalue', np.asarray([5., 15.]))

a.rasterize_zone_valuebyid(z, 'testvalue')
fig, ax = a.plot_matplotlib()

Do not confuse

• rasterize_vector_along_grid : routine of header_wolf class –> rasterize a vector along to the grid - very useful for flow discharge computation bsed on arbitrary cross-sections

• rasterize_vector_valuebyid : routine of WolfArray class –> fill the grid with the value (by its id) inside the polygon formed by the vector

import matplotlib.pyplot as plt
from wolfhece.PyVertex import getRGBfromI, getIfromRGB


v3 = vector(fromnumpy= np.asarray([[25.,25.],
                                  [100.,80.],
                                  [50.,90.],
                                  [60.,10.],
                                  ]))

raster_v3 = a.rasterize_vector_along_grid(v3)

fig, ax = plt.subplots()
raster_v3.plot_matplotlib(ax)

v3.myprop.color = getIfromRGB((255,0,0))
v3.plot_matplotlib(ax)