def min (field,axis=None): 
        import numpy as np
        if field is None: return None
        else: return np.array(field).min(axis=axis)

def max (field,axis=None):
        import numpy as np
        if field is None: return None
        else: return np.array(field).max(axis=axis)

def mean (field,axis=None):
        import numpy as np
        if field is None: return None
        else: return np.array(field).mean(axis=axis)

def deg ():
        return u'\u00b0'

def writeascii ( tab, filename ):
    mydata = tab
    myfile = open(filename, 'w')
    for line in mydata:
        myfile.write(str(line) + '\n')
    myfile.close()
    return