1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
|
"""run test.py first!"""
from pyproj import Proj
import time, cPickle
import numpy as N
nx = 349; ny = 277; dx = 32463.41; dy = dx
print 'do it again, from pickled instance ...'
# find 4 lon/lat crnrs of AWIPS grid 221.
llcrnrx = 0.; llcrnry = 0.
lrcrnrx = dx*(nx-1); lrcrnry = 0.
ulcrnrx = 0.; ulcrnry = dy*(ny-1)
urcrnrx = dx*(nx-1); urcrnry = dy*(ny-1)
dx = (urcrnrx-llcrnrx)/(nx-1)
dy = (urcrnry-llcrnry)/(ny-1)
x = llcrnrx+dx*N.indices((ny,nx),'f')[1,:,:]
y = llcrnry+dy*N.indices((ny,nx),'f')[0,:,:]
awips221 = cPickle.load(open('test.pickle','rb'))
t1 = time.clock()
lons, lats = awips221(x, y, inverse=True, radians=True)
t2 = time.clock()
print 'compute lats/lons for all points on AWIPS 221 grid (%sx%s)' %(nx,ny)
print 'max/min lons in radians'
print N.minimum.reduce(N.ravel(lons)),N.maximum.reduce(N.ravel(lons))
print 'max/min lats in radians'
print N.minimum.reduce(N.ravel(lats)),N.maximum.reduce(N.ravel(lats))
print 'took',t2-t1,'secs'
# reverse transformation.
t1 = time.clock()
xx, yy = awips221(lons, lats, radians=True)
t2 = time.clock()
print 'max abs error for x'
print N.maximum.reduce(N.fabs(N.ravel(x-xx)))
print 'max abs error for y'
print N.maximum.reduce(N.fabs(N.ravel(y-yy)))
print 'took',t2-t1,'secs'
|
