python中定义类的方法很简单，用关键字class， 其中可以包含函数 用 def#!/usr/bin/env python
# -*- coding:UTF-8 -*-
class Test_N:
""" class get a name and count string or number """
def __init__(self, n):
self.name = n
def sqrt_num(self, cn):
if cn >= 0:
root = cn ** 0.5
return -root, root
else:
print "negative number."
return
def c_str(self, cs):
return len(cs)
@staticmethod
def square_list( *args ):
r = []
for i in args:
r.append(i ** 2)
return r
def genome_len(self, fasta):
return len(fasta)
def anno_genome(self , gff):
handle = open(gff, ‘r‘)
n = 0
for i in handle:
n += 1
handle.close()
return n
x = Test_N("Kate") # initiate the class
print x.name
print "Kate\‘s number is 1235678."
print "It\‘s square root are:"
print x.sqrt_num(1235678) # invoke the function sqrt_num
print "Kate\‘s string is agahccp."
print "It\‘s count is:"
print x.c_str("agahccp") # invoke the function c_str
for i in Test_N.square_list(3,4,5,6,7): # invoke the method squre_list
print i
print x.anno_genome("log.txt") # invoke the function anno_genome
输出结果如下Kate
Kate‘s number is 1235678.
It‘s square root are:
(-1111.6105433109205, 1111.6105433109205)
Kate‘s string is agahccp.
It‘s count is:
7
9
16
25
36
49
36
其中log.txt 是一个有36行的文件，所以输出的最后一个数字是36
