"""Utility module to load measurements into Numpy record arrays.
Loading measurement files with the format:
#Station Lat Long Elev
BIRA 26.4840 87.2670 0.0120
BUNG 27.8771 85.8909 1.1910
etc...
"""
import numpy as np
import pylab as plt
# Simple example of usage
# Data descriptor to make a proper array.
dt = [('station','S4'),('lat',np.float32),('lon',np.float32),
('elev',np.float32)]
# This is an alternate and fully equivalent form:
dt = dict(names = ('station','lat','lon','elev'),
formats = ('S4',np.float32,np.float32,np.float32) )
# For more on dtypes, see:
# http://mentat.za.net/numpy/refguide/arrays.recarray.xhtml
import math
def tlog(s):
return np.float32(math.log(float(s)))
tab = np.loadtxt('HIMNTstations2.txt',dt,
converters={1:tlog})
print 'Stations:',tab['station']
print 'Elevations:',tab['elev']
print 'First station:',tab[0]
print 'Mean latitude:',tab['lat'].mean()
plt.figure()
plt.scatter(tab['lat'],tab['lon'],30*tab['elev'],
c=tab['elev'],
cmap=plt.cm.bone,
)
plt.show()
