读取csv的代码：
print pd.read_csv("ex1.csv")
print "\n"
print "Can also use read table with a specific separator"
print pd.read_table("ex1.csv",sep=',')
print "\n"
print "Read a csv and define a row as its header"
print pd.read_csv("ex2.csv",header=None)
print "###"
print pd.read_csv("ex2.csv",header=1)
print "\n"
print 'Set names for the columns'
name=['wang','li','zhao','qian','sun']
print pd.read_csv('ex2.csv',names=name)
print "\n"
print 'Set names for the columns and user a column as the index'
print pd.read_csv('ex2.csv',names=name,index_col='sun')
读取不规则csv到pandas
b = list(open('ex3.txt'))
print b
print 'User regex to split, s represents space,tap,new line, and so forth'
result = pd.read_table('ex3.txt',sep="\s+")
print result
print '\n'
print 'Skip rows from reading'
result1 = pd.read_table('ex3.txt',sep="\s+",skiprows=[1,3])
print result1
print '\n'
print 'We found some NaN somewhere'
csv5 = pd.read_csv('ex5.csv')
print csv5
print pd.isnull(csv5)
print '\n'
print "We treat 'foo' as a NaN"
csv5_fill = pd.read_csv('ex5.csv',na_values=["foo"])
print csv5_fill