import numpy as np
import netCDF4 as cdf
# select non-interactive backend, cf http://stackoverflow.com/questions/4931376/generating-matplotlib-graphs-without-a-running-x-server
import matplotlib
matplotlib.use('Agg') 
import matplotlib.pyplot as plt

def getdims(nc, *names): return [len(nc.dimensions[name]) for name in names]
def getvars(nc, *names): return [nc.variables[name] for name in names]

def axis_longitude():
    plt.xlim((0,360))
    plt.xlabel('longitude (degrees)')
    plt.xticks(np.arange(0,361,30))

def axis_latitude():
    plt.ylim((-90,90))
    plt.ylabel('latitude (degrees)')
    plt.yticks(np.arange(-90,91,30))