import Nio

import time,os

import numpy as np

import matplotlib.pyplot as plt

import matplotlib.mlab as mlab

from mpl_toolkits.basemap import Basemap

from numpy import ma



fname='qscat_winds.csv'



# specify the center of the plotting region and delta lat/lon from the center

lonc=129.0

latc=16.0

delta=2

lonmin=lonc-delta

lonmax=lonc+delta

latmin=latc-delta

latmax=latc+delta



data=np.genfromtxt(fname, dtype="S8,S9,i8,i8,f8,f8,f8,f8,S7,f8,f8,f8,i8,f8", delimiter=',',names=True)

Urows = data[::2]

Vrows = data[1::2]

ziplist = zip(Urows['lat'], Urows['lon'], Urows['obs'], Vrows['obs'], Urows['qcm'], Vrows['qcm'])

ziplist = [(y, x, u, v) for (y, x, u, v, xqc, yqc) in ziplist if xqc == 1 and yqc == 1 and lonmin <= x <= lonmax and latmin <= y <= latmax]

lat, lon, U, V = zip(*ziplist)



fig = plt.figure()

# Resolution: Can be 'c' (crude), 'l' (low), 'i' (intermediate), 'h' (high), 'f' (full) or None.

m = Basemap(projection="cyl",lon_0=np.mean(lonc),lat_0=np.mean(latc),llcrnrlat=np.min(latmin),llcrnrlon=np.min(lonmin),urcrnrlat=np.max(latmax),urcrnrlon=np.max(lonmax),resolution="i")

m.barbs(lon[::20], lat[::20], U[::20], V[::20])

dd = 0.5 # draw meridians at dd degree resolution    

m.drawparallels(np.arange(-90,90,dd),labels=[1,0,0,0], color='black',dashes=[1,0],labelstyle='+/-',linewidth=0.2)

m.drawmeridians(np.arange(-180,180,dd),labels=[0,0,0,1], color='black',dashes=[1,0],labelstyle='+/-',linewidth=0.2)

m.drawcoastlines(linewidth=0.5)

m.drawmapboundary()

m.drawstates()

m.drawcountries()

plt.savefig('qscat-2004062700.png')

plt.clf()