pygridgen

A Python interface to Pavel Sakov's C-based Gridgen Orthogonal Grid Generation Package

Components

• simple GUI interface - The GUI interface uses native matplotlib widgets for even more portability.
• arbitrary number of corners - More corners means more complicated domains. Great for domains with bays, estuaries, and other complicated features.
• a single orthogonal grid as a result - Whites whiter! Brights brighter!

Install

We are working on packaging using Bento or binstar. When that happens it'll be very easy to install. For now, here's a very rough outline.

• cd external/nn; ./configure ; make install
• cd external/csa; ./configure ; make install
• cd external/gridutils; ./configure ; make install
• cd external/gridgen; ./configure ; make shlib
• cd pygridgen; python setup.py install

More details on installation in the documentation:

• Linux
• Mac OS X

Dependencies:

• numpy
• matplotlib
• pyproj or basemap

Examples

Basic Example

import matplotlib.pyplot as plt
import pygridgen
x = [0, 1, 2, 1, 0]
y = [0, 0, 1, 2, 2]
beta = [1, 1, 0, 1, 1]

grid = pygridgen.grid.Gridgen(x, y, beta, shape=(10, 5))

fig, ax = plt.subplots()
ax.plot(x, y, 'k-')
ax.plot(grid.x, grid.y, 'b.')
plt.show()

Example with focus

Note that add_focus_x means focus along the x axis, not at a specific x-postion.

x = [0, 1, 2, 1, 0]
y = [0, 0, 1, 2, 2]
beta = [1, 1, 0, 1, 1]

focus = pygridgen.grid.Focus()
focus.add_focus_x(xo=0.5, factor=3, Rx=0.2)
focus.add_focus_y(yo=0.75, factor=5, Ry=0.1)
grid = pygridgen.grid.Gridgen(x, y, beta, shape=(20, 20), focus=focus)

fig, ax = plt.subplots()
ax.plot(x, y, 'k-')
ax.plot(grid.x, grid.y, 'b.')
plt.show()