python判断字符串是否为小数的方法

'''

1、判断小数点个数是不是1  count

2、分割，判断小数点右边是不是整数

3、判断小数点左边

   是整数is_digit

   如果是负整数，按照'-'符号右边的不会是整数

'''                              

def is_float(s):

    s = str(s)

    if s.count('.') ==1:

        left = s.split('.')[0]

        right = s.split('.')[1]

        if right.isdigit():

            if left.count('-')==1 and left.startswith('-'):

                num = left.split['-'][-1]

                if num.isdigit():

                    return True

            elif left.isdigit():

                return Ture

    return False