<?xml version="1.0" encoding="utf-8" ?><rss version="2.0"><channel><title><![CDATA[i_newbie的博客]]></title><description><![CDATA[]]></description><link>https://blog.youkuaiyun.com/i_newbie</link><language>zh-cn</language><generator>https://blog.youkuaiyun.com/</generator><copyright><![CDATA[Copyright &copy; i_newbie]]></copyright><item><title><![CDATA[conda与pip差别]]></title><link>https://blog.youkuaiyun.com/i_newbie/article/details/148831938</link><guid>https://blog.youkuaiyun.com/i_newbie/article/details/148831938</guid><author>i_newbie</author><pubDate>Sun, 22 Jun 2025 20:15:01 +0800</pubDate><description><![CDATA[因此，为了脚本大小不超过100M，还是建议使用pip安装包。]]></description><category></category></item><item><title><![CDATA[Anaconda批量导入离线包]]></title><link>https://blog.youkuaiyun.com/i_newbie/article/details/126695812</link><guid>https://blog.youkuaiyun.com/i_newbie/article/details/126695812</guid><author>i_newbie</author><pubDate>Sun, 04 Sep 2022 22:51:19 +0800</pubDate><description><![CDATA[Anaconda,离线批量导入包]]></description><category></category></item><item><title><![CDATA[Series转Dataframe注意事项]]></title><link>https://blog.youkuaiyun.com/i_newbie/article/details/126695587</link><guid>https://blog.youkuaiyun.com/i_newbie/article/details/126695587</guid><author>i_newbie</author><pubDate>Sun, 04 Sep 2022 22:22:11 +0800</pubDate><description><![CDATA[series与dataframe转换]]></description><category></category></item><item><title><![CDATA[pandas离线文档获取路径]]></title><link>https://blog.youkuaiyun.com/i_newbie/article/details/126338467</link><guid>https://blog.youkuaiyun.com/i_newbie/article/details/126338467</guid><author>i_newbie</author><pubDate>Sun, 14 Aug 2022 23:43:05 +0800</pubDate><description><![CDATA[pandas离线文档]]></description><category></category></item><item><title><![CDATA[删除重复列名数据]]></title><link>https://blog.youkuaiyun.com/i_newbie/article/details/126337802</link><guid>https://blog.youkuaiyun.com/i_newbie/article/details/126337802</guid><author>i_newbie</author><pubDate>Sun, 14 Aug 2022 23:14:23 +0800</pubDate><description><![CDATA[pandas删除重复列名数据]]></description><category></category></item><item><title><![CDATA[pandas删除重复列]]></title><link>https://blog.youkuaiyun.com/i_newbie/article/details/126294411</link><guid>https://blog.youkuaiyun.com/i_newbie/article/details/126294411</guid><author>i_newbie</author><pubDate>Thu, 11 Aug 2022 22:31:53 +0800</pubDate><description><![CDATA[pandas删除完全重复的列，行列转换]]></description><category></category></item><item><title><![CDATA[loc与iloc的区别]]></title><link>https://blog.youkuaiyun.com/i_newbie/article/details/126293892</link><guid>https://blog.youkuaiyun.com/i_newbie/article/details/126293892</guid><author>i_newbie</author><pubDate>Thu, 11 Aug 2022 22:09:24 +0800</pubDate><description><![CDATA[loc与iloc区别]]></description><category></category></item><item><title><![CDATA[搭建纯净的python环境]]></title><link>https://blog.youkuaiyun.com/i_newbie/article/details/126003898</link><guid>https://blog.youkuaiyun.com/i_newbie/article/details/126003898</guid><author>i_newbie</author><pubDate>Tue, 26 Jul 2022 22:40:41 +0800</pubDate><description><![CDATA[干净的python打包环境]]></description><category></category></item><item><title><![CDATA[pandas调整数据列的顺序]]></title><link>https://blog.youkuaiyun.com/i_newbie/article/details/125983829</link><guid>https://blog.youkuaiyun.com/i_newbie/article/details/125983829</guid><author>i_newbie</author><pubDate>Mon, 25 Jul 2022 22:19:32 +0800</pubDate><description><![CDATA[实用的数据列顺序调整]]></description><category></category></item><item><title><![CDATA[pyinstaller打包命令]]></title><link>https://blog.youkuaiyun.com/i_newbie/article/details/125882344</link><guid>https://blog.youkuaiyun.com/i_newbie/article/details/125882344</guid><author>i_newbie</author><pubDate>Tue, 19 Jul 2022 23:07:02 +0800</pubDate><description><![CDATA[pyinstaller打包]]></description><category></category></item><item><title><![CDATA[【Mysql细节】if结构条件为一个范围值的写法规范]]></title><link>https://blog.youkuaiyun.com/i_newbie/article/details/124721142</link><guid>https://blog.youkuaiyun.com/i_newbie/article/details/124721142</guid><author>i_newbie</author><pubDate>Wed, 11 May 2022 22:57:53 +0800</pubDate><description><![CDATA[if语句的第一个表达式如果是一个范围，可以拆分为两个表达式并通过and连接，如下所示
select score,if(score&gt;=70 and score&lt;80,1,0) as mendium
from sc;


但是，绝对不能直接如下所示，否则结果全是真，不符合需求
select score,if(70&lt;=score&lt;80,1,0) as mendium
from sc;



...]]></description><category></category></item><item><title><![CDATA[【Mysql细节】插入日期数据报格式错误：Data truncation: Incorrect datetime value]]></title><link>https://blog.youkuaiyun.com/i_newbie/article/details/124649769</link><guid>https://blog.youkuaiyun.com/i_newbie/article/details/124649769</guid><author>i_newbie</author><pubDate>Sun, 08 May 2022 16:21:24 +0800</pubDate><description><![CDATA[看图吧：
为什么会在插入的第四条数据报格式错误呢？
首先这些插入数据是直接复制的（不是纯手写）。看到报错第一反应是不是觉得自己的数据格式有问题啊，细看又没有发现有啥问题。
那我是如何解决的呢？
1.先把第一条插入的日期数据改为xxxx/xx/xx格式，运行可行
2.再把第二条第三条的日期数据的‘-’删除，自己手打，运行可行
结论
所以真的是想打人了，复制的数据出问题可能需要自己手打一遍检验。细节细节！

...]]></description><category></category></item><item><title><![CDATA[pandas灵活增加新的空字段]]></title><link>https://blog.youkuaiyun.com/i_newbie/article/details/124373984</link><guid>https://blog.youkuaiyun.com/i_newbie/article/details/124373984</guid><author>i_newbie</author><pubDate>Sun, 24 Apr 2022 01:58:38 +0800</pubDate><description><![CDATA[先说需求：从mongodb中读取数据的某些字段（如A,B,C,D），如果数据没有某个字段（如‘D’字段），就增加该字段且值为空
解决方法：
import pandas as pd
import numpy as np
 
a=np.array([[1,2,3],[4,5,6],[7,8,9]])
df1=pd.DataFrame(a,index=['row0','row1','row2'],columns=list('ABC'))
df1


df1结果：

创建空的且有指定字段的dataframe
df2]]></description><category></category></item><item><title><![CDATA[ValueError: The truth value of a Series is ambiguous]]></title><link>https://blog.youkuaiyun.com/i_newbie/article/details/124338063</link><guid>https://blog.youkuaiyun.com/i_newbie/article/details/124338063</guid><author>i_newbie</author><pubDate>Fri, 22 Apr 2022 09:43:36 +0800</pubDate><description><![CDATA[if df1[df1.销售方式=='B']['成交总金额']&gt;0:

这种方式写报错，真值模糊

]]></description><category></category></item><item><title><![CDATA[【pandas】读取excel文件表格并对字段进行数据转换]]></title><link>https://blog.youkuaiyun.com/i_newbie/article/details/124239345</link><guid>https://blog.youkuaiyun.com/i_newbie/article/details/124239345</guid><author>i_newbie</author><pubDate>Sun, 17 Apr 2022 23:41:47 +0800</pubDate><description><![CDATA[df = pd.read_excel('案例流水数据.xlsx',
                                    sheet_name = 'Sheet1',
                                    dtype = {'门店编码':str,
                                                     '单号':str,
                                           ]]></description><category></category></item><item><title><![CDATA[【MySQL写法细节】那些不知不觉就会犯的错误]]></title><link>https://blog.youkuaiyun.com/i_newbie/article/details/123359781</link><guid>https://blog.youkuaiyun.com/i_newbie/article/details/123359781</guid><author>i_newbie</author><pubDate>Tue, 08 Mar 2022 18:16:11 +0800</pubDate><description><![CDATA[SELECT u.name,g.grade_num
from (select user_id,sum(grade_num) grade_num
      from grade_info
      group by user_id
      ) g
join `user` u on g.user_id = u.id
where g.grader_num = (SELECT max(g.grade_num) from g)

这种写法有个错误：
为什么不能在子查询的表格基础上，再做一次子查询？？？

..]]></description><category></category></item><item><title><![CDATA[mysql日期格式]]></title><link>https://blog.youkuaiyun.com/i_newbie/article/details/123023880</link><guid>https://blog.youkuaiyun.com/i_newbie/article/details/123023880</guid><author>i_newbie</author><pubDate>Sat, 19 Feb 2022 21:00:55 +0800</pubDate><description><![CDATA[注意时分秒：%H：%i：%s
select DATE_FORMAT(created_at,'%Y-%m-%d %H:%i:%s') as `DATE_FORMAT


]]></description><category></category></item><item><title><![CDATA[使用 decorator 实现一个函数计时器]]></title><link>https://blog.youkuaiyun.com/i_newbie/article/details/122475807</link><guid>https://blog.youkuaiyun.com/i_newbie/article/details/122475807</guid><author>i_newbie</author><pubDate>Thu, 13 Jan 2022 16:05:03 +0800</pubDate><description><![CDATA[实例：
decorators.py
import time
def timer(func):
    def wrapper(*args, **kwargs):
    	#函数花费时间由两个时间方法和该函数组成
        t = time.time()    
        func(*args, **kwargs)
        t = time.time() - t  
        print(f"function {func.__name__} cost {t:.1f} seconds]]></description><category></category></item><item><title><![CDATA[批量复制源目录下的文件到新路径]]></title><link>https://blog.youkuaiyun.com/i_newbie/article/details/122473070</link><guid>https://blog.youkuaiyun.com/i_newbie/article/details/122473070</guid><author>i_newbie</author><pubDate>Thu, 13 Jan 2022 14:36:35 +0800</pubDate><description><![CDATA[os.path模块
shutil模块
shutil.rmtree(src):递归删除一个目录以及目录内的所有内容shutil.copytree(“olddir”,“newdir”)
使用该方法之前，newdir保证不存在。因为执行该方法时，系统会创建newdir。所以在使用该方法批量复制文件前，需要判断你新建的newdir是否存在
例子：
if os.path.exists(to_dir_path):
        shutil.rmtree(to_dir_path)
shutil.copytree(fr]]></description><category></category></item><item><title><![CDATA[python3 map()函数]]></title><link>https://blog.youkuaiyun.com/i_newbie/article/details/122461698</link><guid>https://blog.youkuaiyun.com/i_newbie/article/details/122461698</guid><author>i_newbie</author><pubDate>Wed, 12 Jan 2022 20:35:09 +0800</pubDate><description><![CDATA[描述
map() 会根据提供的函数对指定序列做映射。
第一个参数 function 以参数序列中的每一个元素调用 function 函数，返回包含每次 function 函数返回值的新列表。
语法
map() 函数语法：
map(function, iterable, …)
参数
function – 函数
iterable – 一个或多个序列
实例.：
将列表的字符串元素转为int类型
map(int, [‘1’,‘2’,‘3’,‘4’,‘5’])   &gt;&gt;&gt;[1, 2, 3, 4, 5]]></description><category></category></item></channel></rss>