python数据类型转换
一、int函数能够
（1）把符合数学格式的数字型字符串转换成整数
（2）把浮点数转换成整数，但是只是简单的取整，而非四舍五入。
1 aa = int("124") #Correct 2 print "aa = ", aa #result=124 3 bb = int(123.45) #correct 4 print "bb = ", bb #result=123 5 cc = int("-123.45") #Error,Can't Convert to int 6 print "cc = ",cc 7 dd = int("34a") #Error,Can't Convert to int 8 print "dd = ",dd 9 ee = int("12.3") #Error,Can't Convert to int 10 print ee
二、float函数将整数和字符串转换成浮点数。
aa = float("124") #Correct print "aa = ", aa #result = 124.0 bb = float("123.45") #Correct print "bb = ", bb #result = 123.45 cc = float(-123.6) #Correct print "cc = ",cc #result = -123.6 dd = float("-123.34") #Correct print "dd = ",dd #result = -123.34 ee = float('123v') #Error,Can't Convert to float print ee
三、str函数将数字转换成字符
aa = str(123.4) #Correct print aa #result = '123.4' bb = str(-124.a) #SyntaxError: invalid syntax print bb cc = str("-123.45") #correct print cc #result = '-123.45' dd = str('ddd') #correct print dd #result = ddd ee = str(-124.3) #correct print ee #result = -124.3
