day4_生成小数的程序

def is_float(s):
    s = str(s).strip()
    if s.count('.') == 1:
        left, right = s.split('.')
        if left.isdigit() and right.isdigit():  # 正小数
            return True
        # 负小数
        elif left.startswith('-') and left.count('-') == 1 and\
                left.split('-')[-1].isdigit() and right.isdigit():
            return True
    return False


print(is_float('-.1'))
print(is_float('5.1'))
print(is_float('5.q'))
print(is_float('5.q.1'))
print(is_float('-5.1'))
print(is_float('--5.1'))
print(is_float('-a.1'))
print(is_float('.1'))
print(is_float('a.1'))
print(is_float('a12'))
print(is_float('2..22-5.6'))