一、概述
写好的代码能直接运行的概率非常低，总会在不经意间出现各种各样的BUG，有的BUG很简单，看看错误提示就能修改好。但是有的BUG很复杂，需要一些调试的手段来发现并解决错误
二、print
print是最简单最原始的调试方式
代码语言：javascript复制<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">func</span><span class="hljs-params">(x)</span>:</span>
print(<span class="hljs-string">"-----------1"</span>)
print(x)
ret = <span class="hljs-number">10</span> / x
print(<span class="hljs-string">"-----------2"</span>)
<span class="hljs-keyword">return</span> ret
func(<span class="hljs-number">0</span>)缺点：将来得删除调试的print，运行结果也会包含一些垃圾信息
三、断言
使用
凡是用print来辅助调试的地方，都可以缓存断言(assert)语句
逻辑
当程序执行到assert语句时，首先计算第一个表达式的值，如果值为真则继续向下运行。否则断言失败，assert语句会抛出AssertionError异常，异常的信息为第二个表达式的值
缺点
如果将所有的print换成assert也好不到哪里去
优点
在启动程序时可以通过命令参数关闭assert
代码
代码语言：javascript复制<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">func</span><span class="hljs-params">(x)</span>:</span>
<span class="hljs-keyword">assert</span> x != <span class="hljs-number">0</span>, <span class="hljs-string">"x is zero"</span>
ret = <span class="hljs-number">10</span> / x
<span class="hljs-keyword">return</span> ret
func(<span class="hljs-number">0</span>)四、logging
使用：把所有的print替换成logging也是可以的，和assert相比logging不会抛出异常，把错误输入到文件
代码语言：javascript复制<span class="hljs-keyword">import</span> logging
<span class="hljs-comment">#配置输出级别</span>
logging.basicConfig(level=logging.ERROR)
<span class="hljs-string">'''
CRITICAL = 50
FATAL = CRITICAL
ERROR = 40
WARNING = 30
WARN = WARNING
INFO = 20
DEBUG = 10
NOTSET = 0
'''</span>
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">func</span><span class="hljs-params">(x)</span>:</span>
logging.error(<span class="hljs-string">"x = %d"</span>%(x))
ret = <span class="hljs-number">10</span> / x
<span class="hljs-keyword">return</span> ret
func(<span class="hljs-number">0</span>)五、pdb
使用
python的调试器，让程序以单步方式一句一句的运行，可以随时查看运行的状态
以pdb方式调试代码
需要使用黑屏终端： python -m pdb 文件名称
调试命令
n：单步执行代码
p： 变量名
q：退出调试
基本使用
代码语言：javascript复制a = <span class="hljs-number">1</span>
print(<span class="hljs-string">"-------------------------0"</span>)
b = a <span class="hljs-number">1</span>
print(<span class="hljs-string">"-------------------------1"</span>)
print(<span class="hljs-string">"-------------------------2"</span>)
c = <span class="hljs-number">2</span>
print(<span class="hljs-string">"-------------------------3"</span>)
print(<span class="hljs-string">"-------------------------4"</span>)
print(<span class="hljs-string">"-------------------------5"</span>)
d = <span class="hljs-number">0</span>
print(<span class="hljs-string">"-------------------------6"</span>)
c / d
print(<span class="hljs-string">"-------------------------7"</span>)
print(<span class="hljs-string">"-------------------------8"</span>)
f = <span class="hljs-number">10</span>
print(<span class="hljs-string">"-------------------------9"</span>)缺点：麻烦，如果有100000代码，认为错误可能出现在第9000左右，需要运行到9000行才行
自定义开始断点
代码语言：javascript复制<span class="hljs-keyword">import</span> pdb
a = <span class="hljs-number">1</span>
print(<span class="hljs-string">"-------------------------0"</span>)
b = a <span class="hljs-number">1</span>
print(<span class="hljs-string">"-------------------------1"</span>)
print(<span class="hljs-string">"-------------------------2"</span>)
c = <span class="hljs-number">2</span>
print(<span class="hljs-string">"-------------------------3"</span>)
print(<span class="hljs-string">"-------------------------4"</span>)
print(<span class="hljs-string">"-------------------------5"</span>)
d = <span class="hljs-number">0</span>
<span class="hljs-comment">#自定义断点</span>
pdb.set_trace()
print(<span class="hljs-string">"-------------------------6"</span>)
c / d
print(<span class="hljs-string">"-------------------------7"</span>)
print(<span class="hljs-string">"-------------------------8"</span>)
f = <span class="hljs-number">10</span>
print(<span class="hljs-string">"-------------------------9"</span>)六、IDE断点
代码语言：javascript复制<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">func</span><span class="hljs-params">()</span>:</span>
print(<span class="hljs-string">"**********1"</span>)
print(<span class="hljs-string">"**********2"</span>)
print(<span class="hljs-string">"**********3"</span>)
print(<span class="hljs-string">"**********4"</span>)
a = <span class="hljs-number">1</span>
print(<span class="hljs-string">"-------------------------0"</span>)
b = a <span class="hljs-number">1</span>
print(<span class="hljs-string">"-------------------------1"</span>)
print(<span class="hljs-string">"-------------------------2"</span>)
c = <span class="hljs-number">2</span>
print(<span class="hljs-string">"-------------------------3"</span>)
print(<span class="hljs-string">"-------------------------4"</span>)
func()
print(<span class="hljs-string">"-------------------------5"</span>)
d = <span class="hljs-number">0</span>
print(<span class="hljs-string">"-------------------------6"</span>)
c / d
print(<span class="hljs-string">"-------------------------7"</span>)
print(<span class="hljs-string">"-------------------------8"</span>)
f = <span class="hljs-number">10</span>
print(<span class="hljs-string">"-------------------------9"</span>)
