python-问题解决

雨点打透心脏的1/2处 2021-09-23 10:36 4403阅读 0赞

*  can't multiply sequence by non-int of type 'str'
 *  invalid decimal literal
 *  ValueError: math domain error
 *  missing whitespace after ‘,’
 *  missing whitespace around operator
 *  no newline at end of file
 *  PEP 8: expected 2 blank lines after class or function definition, found 1
 *  This dictionary creation could be rewritten as a dictionary literal

**（标题）can't multiply sequence by non-int of type 'str'**

![20200627225622317.png][]

通过键盘输入返回值的类型是字符串，要进行数学运算要强制转换

//像java这样：int a在这里是无效语法
    
    //可以这样（两种方式都可以）
    1：a = int(input('请输入乘数:'))
    2：int(a)*int(b)

**（标题）invalid decimal literal**

![20200803004911863.png][]

翻译了一下：十进制文本无效

这里犯了个打错，变量的命名规则呀，不能数字开头

**（标题）ValueError: math domain error**

![20191105205042412.png][]

![20191105205102751.png][]

报错

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjcxNzkyOA_size_16_color_FFFFFF_t_70][]

原因：某些操作不符合数学定义，如对负数取对数，对负数开平方

问题出现在这里：

![20191105205337690.png][]

取值为10,20,30的时候，里面是负数，不符合

**（标题）missing whitespace after ‘,’**

![20200627222735912.png][]

解决方法：逗号后面加个空格

**（标题）missing whitespace around operator**

![20200627223147207.png][]

解决方法：=左右各加一个空格

**（标题）no newline at end of file**

![20200627221351974.png][]

看到一个 warning：no newline at end of file

文件每一行都以换行结束，只需要在文件结尾回车即可

具体原因：

避免include文件时，展开后与后面的文件连为一行，造成错误。

**（标题）PEP 8: expected 2 blank lines after class or function definition, found 1**

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjcxNzkyOA_size_16_color_FFFFFF_t_70 1][]

**意思是“有两个空白行，但是没有发现。”**

**在声明函数的那一行的上方必须有两行的空行，否则便出现这个情况。**

**（标题）This dictionary creation could be rewritten as a dictionary literal**

![20200801215012369.png][]

之所以出现这个的原因，是因为这两句可以合并

更多其他关闭这个提示：[https://stackoverflow.com/questions/8406242/why-does-pycharms-inspector-complain-about-d][https_stackoverflow.com_questions_8406242_why-does-pycharms-inspector-complain-about-d]

[20200627225622317.png]: /images/20210923/454c5cdad69a4d12a7a6923652a730bd.png
[20200803004911863.png]: /images/20210923/ceb62d4f80fd4e50a0a89a5680d407ad.png
[20191105205042412.png]: /images/20210923/cbe3f9c215e140d581f997a82ed5f3c7.png
[20191105205102751.png]: /images/20210923/6ac00d873c5d4892a05469518493c951.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjcxNzkyOA_size_16_color_FFFFFF_t_70]: /images/20210923/62f68bf1822746a6bab2703325907b2c.png
[20191105205337690.png]: /images/20210923/42ea98a5412b48f9a7b2c691323aea2e.png
[20200627222735912.png]: /images/20210923/5509b5cb8a88403f8c30b3166af5fbfd.png
[20200627223147207.png]: /images/20210923/b5971d6da2c2480e8af593c7556ebda1.png
[20200627221351974.png]: /images/20210923/9881de5901664aa79c3b25ef2b323a50.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjcxNzkyOA_size_16_color_FFFFFF_t_70 1]: /images/20210923/a5ae043b7fe44402a97b8831707c44c3.png
[20200801215012369.png]: /images/20210923/2e20bd5f238645cf831fb69b00edf8b4.png
[https_stackoverflow.com_questions_8406242_why-does-pycharms-inspector-complain-about-d]: https://stackoverflow.com/questions/8406242/why-does-pycharms-inspector-complain-about-d