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Conditionally Remove Dataframe Rows with R [duplicate]
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Logic index:
d<-d[!(d$A=="B" & d$E==0),]
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[源码实例] c/c++获取网卡mac地址 - C/C++ - 清泛网 - 专注C/C++及内核技术
...mac地址代码如下：#include "stdafx.h"#include <afx.h>#include < nb30.h > #pragma comment(lib,"netapi32.lib")typedef struct _ASTAT...代码如下：
#include "stdafx.h"
#include <afx.h>
#include < nb30.h >
#pragma comment(lib,"netapi32.lib")
typedef struct _ASTAT_
{
ADAPTER_STA...
MFC 日期时间控件CDateTimeCtrl自绘 - C/C++ - 清泛网 - 专注C/C++及内核技术
...绘先看效果：方法同ComboBox自绘（http: www.tsingfun.com html 2016 code_1110 100.html），采用图片拼接的方式，本例实现较基础仍有细节待...先看效果：
方法同ComboBox自绘（https://www.tsingfun.com/down/code/100.html），采用图片拼接的方式，本...
CSS3滚动条美化效果 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...sparent;
}
::-webkit-scrollbar-track {
box-shadow: 1px 1px 5px rgba(0,0,0,.2) inset;
}
::-webkit-scrollbar-thumb {
min-height: 20px;
background-clip: content-box;
box-shadow: 0 0 0 5px rgba(0,0,0,.2) inset;
}
::-webkit-scrollbar-corner {
background: transparent;
}
如...
css中@media screen and (-webkit-min-device-pixel-ratio:0)解析 - 更多技...
css中@media screen and (-webkit-min-device-pixel-ratio:0)解析@media screen and (-webkit-min-device-pixel-ratio:0) {.down_info caption h5{height:60px; line-height:60px;}}Webkit内核浏览...
@media screen and (-webkit-min-device-pixel-ratio:0) {
.down_info caption h5{height:60px; line-height:60...
Arduino控制RGB三色LED灯实验、程序代码、连线图、仿真 - 创客硬件开发 - ...
...控制，针对Arudino UNO板子中带有"~"的3、5、6、9、10、11数字端口写入一个模拟值，通知高电平与低电平持续时间的比值控制LED的亮度变化或者电机的转速。例如：欲使得内置的Arudino UNO 中的led亮度变为原来的一般，编写anal...
How do I resolve cherry-pick conflicts using their changes?
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201
First you should undo your cherry-pick, try to run this
git cherry-pick --abort
Second, try ...
How do I change the figure size with subplots?
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answered Feb 8 '13 at 10:48
Rutger KassiesRutger Kassies
41.9k1111 gold badges9090 silver badges9090 bronze badges
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Python serialization - Why pickle?
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edited Jan 28 '14 at 23:06
answered Jan 23 '12 at 8:45
au...
Eager load polymorphic
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209
My guess is that your models look like this:
class User < ActiveRecord::Base
has_many :re...