7

所以我试图测试是否有回文。这是我的代码：

此函数返回一个较大字符串的前半部分的字符串。（“TEST”返回“TE”，“HELLO”返回“HE”）

def takeStart(s):
    start = ""

    # The following determines the final index of the first half

    if len(s)%2==0:  
        a = (len(s)/2)-1
    else:
        a = ((len(s)-1)/2)-1

    for i in range(a):
        start+=s[i]
    return start

此函数返回较大字符串的后半部分的字符串。（“TEST”返回“ST”，“HELLO”返回“LO”）

def takeEnd(s):  
    end = ""

    # The following determines the beginning index of the second half

    if len(s)%2==0:
        a = (len(s)/2)
    else:
        a = ((len(s)-1)/2)

    for i in range(a,len(s)):
        end+=s[i]
    return end

这个函数翻转一个字符串。（“TEST”返回“TSET”，“HELLO”返回“OLLEH”）

def flip(s):
    flipped = ""
    for i in range(1,len(s)):
        flipped+=s[len(s)-i]
    flipped+=s[0]
    return flipped

此代码获取两个 3 位数字的每个乘积，并检查它是否是回文

for i in range(100,1000):
    for q in range(100,1000):
        a = i*q
        if takeStart(str(a)) == flip(takeEnd(str(a))):
            print(str(a))

运行此代码时，它会输出：

Traceback (most recent call last):
  File "[redacted]", line 39, in <module>
    if takeStart(str(a)) == flip(takeEnd(str(a))):
  File "[redacted]", line 14, in takeStart
    for i in range(a):
TypeError: 'float' object cannot be interpreted as an integer

好吧，我以为我只是将 a 转换为整数，一切都应该膨胀。

这样做似乎可以消除所有错误，但没有任何输出。（每隔一段时间就会有新行，这让我觉得它正在工作但没有输出任何数据）

关于为什么会发生这种情况的任何想法？

更新：我现在的代码：

def takeStart(s):
    start = ""
    if len(s)%2==0:
        a = (len(s)//2)
    else:
        a = (len(s)-1)//2
    return start[0:a]

def takeEnd(s):  
    end = ""
    if len(s)%2==0:
        a = (len(s)//2)
    else:
        a = ((len(s)-1)//2)

    return end[int(a):len(s)]

def flip(s):
    return s[::-1]

for i in range(100,1000):
    for q in range(100,1000):
        a = i*q
        if takeStart(str(a)) == flip(takeEnd(str(a))):
            print(str(a))

这只是输出每个数字。我测试了每种方法，它们返回的是空字符串。（我假设），这就是为什么每个数字都通过回文检查和打印的原因。

4

2 回答 2

11
于 2013-10-22T00:54:11.020 回答
0

Pythons range() function does not support floats but numpys arange() function does

To use arange() function, you need to install and import the numpy package. We’ll here use the arange() function for generating a range of float numbers. The arange() has the same signature as the built-in range() method. But we can pass float type arguments as parameters to this function.

import numpy
arange (start, stop, step)

In a full code example this looks as follows:

from numpy import arange

print("Float range using NumPy arange():")

print("\nTest 1:")
for i in arange(0.0, 1.0, 0.1):
    print(i, end=', ')
于 2019-08-27T11:39:13.110 回答