def get_closest_index(latlons, stationll):
"""
Returns the indices of the four surrounding gridpoints in _latlons_ around _stationll_
"""
import get_closest_gridpoint as getpoint
lats, lons = latlons
latt, lont = stationll
print 'point of interest (lat,lon) ', latt, lont
g = getpoint.grid_searcher(lats, lons, method=2)
a, b, c, d = g.get_four_surrounding_points(latt, lont)
index = (a, b, c, d)
print 'Index:', index
indices = ((index[0], index[2]), (index[0], index[3]),
(index[1], index[3]), (index[1], index[2]))
print 'Indices of 4 surrounding points: ', indices
return indices
def multi_interp(listdictvalues,
latlons,
stationlllist,
indices=None,
method='bilinear'):
'''
assume a number of fields to be interpolated, and a number of points
Gather the interpolation characteristics to reuse(!)
'''
import get_closest_gridpoint as getpoint
lats, lons = latlons
#latt,lont = stationll
try:
f = open('line_intp.pkl')
linedict = pickle.load(f)
except:
print 'no predefined coefficients available, compute'
#if indices is None:
indices = {}
for s, ll in enumerate(stationlllist):
latt, lont = ll
print 'point of interest (lat,lon) ', latt, lont
g = getpoint.grid_searcher(lats, lons, method=2)
a, b, c, d = g.get_four_surrounding_points(latt, lont)
index = (a, b, c, d)
print 'Index:', index
indices[s] = ((index[0], index[2]), (index[0], index[3]),
(index[1], index[3]), (index[1], index[2]))
print 'Indices of 4 surrounding points: ', indices[s]
lata, lona = lats[indices[0]], lons[indices[s][0]]
latb, lonb = lats[indices[1]], lons[indices[s][1]]
latc, lonc = lats[indices[2]], lons[indices[s][2]]
latd, lond = lats[indices[3]], lons[indices[s][3]]
if method == 'bilinear':
xa, xb, xc, xd = {}, {}, {}, {}
ya, yb, yc, yd = {}, {}, {}, {}
distab, distbc, distcd, distda = {}, {}, {}, {}
xa[s] = getpoint.get_distance_grcircle(lata, lona, lata, lont)
xb[s] = getpoint.get_distance_grcircle(latb, lonb, latb, lont)
xc[s] = getpoint.get_distance_grcircle(latc, lonc, latc, lont)
xd[s] = getpoint.get_distance_grcircle(latd, lond, latd, lont)
ya[s] = getpoint.get_distance_grcircle(lata, lona, latt, lona)
yb[s] = getpoint.get_distance_grcircle(latb, lonb, latt, lonb)
yc[s] = getpoint.get_distance_grcircle(latc, lonc, latt, lonc)
yd[s] = getpoint.get_distance_grcircle(latd, lond, latt, lond)
#yab[s] = getpoint.get_distance_grcircle(lata,lona,latt,lona)
#distap = getpoint.get_distance_grcircle(lata,lona,latt,lont)
#distbp = getpoint.get_distance_grcircle(latb,lonb,latt,lont)
#distcp = getpoint.get_distance_grcircle(latc,lonc,latt,lont)
#distdp = getpoint.get_distance_grcircle(latd,lond,latt,lont)
distab[s] = getpoint.get_distance_grcircle(
lata, lona, latb, lonb)
distbc[s] = getpoint.get_distance_grcircle(
latc, lonc, latb, lonb)
distcd[s] = getpoint.get_distance_grcircle(
latc, lonc, latd, lond)
distda[s] = getpoint.get_distance_grcircle(
lata, lona, latd, lond)
for l in listdictvalues.keys():
a = values[indices[0]]
b = values[indices[1]]
c = values[indices[2]]
d = values[indices[3]]
print indices, a, b, c, d
# bilinear:
#pab = a * xb[s] / distab[s] + b * xa[s] / distab[s]
#pcd = d * xc[s] / distab[s] + c * xd[s] / distcd[s]
pvalue = (yd[s] * xb[s] / (distab[s] * distda[s]) +
yc[s] * xa[s] / (distab[s] * distbc[s]) +
yb[s] * xd[s] / (distcd[s] * distbc[s]) +
ya[s] * xc[s] / (distcd[s] * distda[s]))
#pvalue = pab * ycd / distda + pcd * yab / distda[s]
print 'dus ', a, b, c, d, pvalue
print 'en ', xa[s], xb[s], xc[s], xd[
s], xa[s] + xb[s], xc[s] + xd[s]
if 0: # debug
print a, b, xb, xa, distab
print lata, latb, ya, yb, yab
print latc, latd, yc, yd, ycd
print pab, pcd, pvalue
return pvalue
else: # return average (?)
return (a + b + c + d) / 4.
def interp(values, latlons, stationll, indices=None, method='bilinear'):
import get_closest_gridpoint as getpoint
lats, lons = latlons
latt, lont = stationll
try:
f = open('line_intp.pkl')
linedict = pickle.load(f)
except:
print 'no predefined coefficients available, compute'
if indices is None:
print 'point of interest (lat,lon) ', latt, lont
g = getpoint.grid_searcher(lats, lons, method=2)
a, b, c, d = g.get_four_surrounding_points(latt, lont)
index = (a, b, c, d)
print 'Index:', index
indices = ((index[0], index[2]), (index[0], index[3]),
(index[1], index[3]), (index[1], index[2]))
print 'Indices of 4 surrounding points: ', indices
elif indices is not None and len(indices) < 4:
return values[indices[0], indices[1]]
if 1:
a = values[indices[0]]
b = values[indices[1]]
c = values[indices[2]]
d = values[indices[3]]
#print indices,a,b,c,d
lata, lona = lats[indices[0]], lons[indices[0]]
latb, lonb = lats[indices[1]], lons[indices[1]]
latc, lonc = lats[indices[2]], lons[indices[2]]
latd, lond = lats[indices[3]], lons[indices[3]]
if method == 'bilinear':
latt, lont = stationll
xa = getpoint.get_distance_grcircle(lata, lona, lata, lont)
xb = getpoint.get_distance_grcircle(latb, lonb, latb, lont)
xc = getpoint.get_distance_grcircle(latc, lonc, latc, lont)
xd = getpoint.get_distance_grcircle(latd, lond, latd, lont)
ya = getpoint.get_distance_grcircle(lata, lona, latt, lona)
yb = getpoint.get_distance_grcircle(latb, lonb, latt, lonb)
yc = getpoint.get_distance_grcircle(latc, lonc, latt, lonc)
yd = getpoint.get_distance_grcircle(latd, lond, latt, lond)
#yab = getpoint.get_distance_grcircle(lata,lona,latt,lona)
distap = getpoint.get_distance_grcircle(lata, lona, latt, lont)
distbp = getpoint.get_distance_grcircle(latb, lonb, latt, lont)
distcp = getpoint.get_distance_grcircle(latc, lonc, latt, lont)
distdp = getpoint.get_distance_grcircle(latd, lond, latt, lont)
distab = getpoint.get_distance_grcircle(lata, lona, latb, lonb)
distbc = getpoint.get_distance_grcircle(latc, lonc, latb, lonb)
distcd = getpoint.get_distance_grcircle(latc, lonc, latd, lond)
distda = getpoint.get_distance_grcircle(lata, lona, latd, lond)
# bilinear:
pab = a * xb / distab + b * xa / distab
pcd = d * xc / distab + c * xd / distcd
yab = ya * xb / distab + yb * xa / distab
ycd = yd * xc / distab + yc * xd / distcd
pvalue = pab * ycd / distda + pcd * yab / distda
if 0: # debug
print a, b, xb, xa, distab
print lata, latb, ya, yb, yab
print latc, latd, yc, yd, ycd
print pab, pcd, pvalue
return pvalue
else: # return average (?)
return (a + b + c + d) / 4.
def compute_dist(self, verb=True):
'''
get all distances in "square" around point of interest:
d - c a - b
| t | or | |
a - b d - c
'''
lats, lons = self.latlons
for s, ll in enumerate(self.stationll):
latt, lont = ll
if verb: print 'point of interest (lat,lon) ', s, latt, lont
g = getpoint.grid_searcher(lats, lons, method=2)
a, b, c, d = g.get_four_surrounding_points(latt, lont)
index = (a, b, c, d)
print 'Index:', index
self.indices[s] = ((index[0], index[2]), (index[0], index[3]),
(index[1], index[3]), (index[1], index[2]))
if verb: print 'Indices of 4 surrounding points: ', self.indices[s]
lata, lona = lats[self.indices[s][0]], lons[self.indices[s][0]]
latb, lonb = lats[self.indices[s][1]], lons[self.indices[s][1]]
latc, lonc = lats[self.indices[s][2]], lons[self.indices[s][2]]
latd, lond = lats[self.indices[s][3]], lons[self.indices[s][3]]
self.xa[s] = getpoint.get_distance_grcircle(lata, lona, lata, lont)
self.xb[s] = getpoint.get_distance_grcircle(latb, lonb, latb, lont)
self.xc[s] = getpoint.get_distance_grcircle(latc, lonc, latc, lont)
self.xd[s] = getpoint.get_distance_grcircle(latd, lond, latd, lont)
self.ya[s] = getpoint.get_distance_grcircle(lata, lona, latt, lona)
self.yb[s] = getpoint.get_distance_grcircle(latb, lonb, latt, lonb)
self.yc[s] = getpoint.get_distance_grcircle(latc, lonc, latt, lonc)
self.yd[s] = getpoint.get_distance_grcircle(latd, lond, latt, lond)
self.distab[s] = getpoint.get_distance_grcircle(
lata, lona, latb, lonb)
self.distbc[s] = getpoint.get_distance_grcircle(
latc, lonc, latb, lonb)
self.distcd[s] = getpoint.get_distance_grcircle(
latc, lonc, latd, lond)
self.distda[s] = getpoint.get_distance_grcircle(
lata, lona, latd, lond)
#self.yab[s] = self.ya[s] * self.xb[s] / self.distab[s] + self.yb[s] * self.xa[s] / self.distab[s]
#self.ycd[s] = self.yd[s] * self.xc[s] / self.distab[s] + self.yc[s] * self.xd[s] / self.distcd[s]
self.xcorr[s] = (self.distab[s] / (self.xa[s] + self.xb[s]))
self.ycorr[s] = (self.distda[s] / (self.ya[s] + self.yd[s]))
if verb:
print 'check x (xa+xb,xc+xd)', self.xa[s] + self.xb[
s], self.xc[s] + self.xd[s]
print 'check y (ya+yd,yb+yc)', self.ya[s] + self.yd[
s], self.yb[s] + self.yc[s]
print 'check corr x', (self.xa[s] +
self.xb[s]) * (self.xcorr[s])
print 'check corr y', (self.ya[s] +
self.yd[s]) * (self.ycorr[s])
print 'check dist (ab,bc,cd,da)', self.distab[s], self.distbc[
s], self.distcd[s], self.distda[s]
values = grbs[1].values
values2 = grbs[2].values
values3 = grbs[3].values
values = grbs[5].values
values2 = grbs[6].values
values3 = grbs[7].values
grbs.close()
latt, lont = 52.376, 4.879
latt, lont = 52.372, 4.85
latt, lont = 52.361, 4.845
llstat = (latt, lont)
g = getpoint.grid_searcher(lats, lons, method=2)
s = g.get_closest_point(latt, lont)
a, b, c, d = g.get_four_surrounding_points(latt, lont)
pts = (a, b, c, d)
indic = ((pts[0], pts[2]), (pts[0], pts[3]), (pts[1], pts[3]), (pts[1],
pts[2]))
print('\n===== The index and lat,lon of closest gridpoint: =====')
print latt, lont
print 'single point: ', s, lats[s], lons[s]
print 'four points: ', a, b, c, d
print('\n===== The indices and values of the surrounding points: =====')
print indic
for i in indic:
print 'lat,lon,value: ', lats[i], lons[i], values[i]