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Drop unused factor levels in a subsetted data frame
...columns in a dataframe, you can use:
subdf <- subset(df, numbers <= 3)
subdf[] <- lapply(subdf, function(x) if(is.factor(x)) factor(x) else x)
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console.log javascript [Function]
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Benjamin
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answered Feb 27 '12 at 6:26
PaulPaul
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Xcode Command /usr/bin/codesign failed with exit code 1 : errSecInternalComponent
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edited Mar 30 '19 at 23:36
Ben Leggiero
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In Vim, how do you search for a word boundary character, like the \b in regexp?
...ynonym to "regex".
– henrebotha
May 3 '18 at 12:33
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Setting global styles for Views in Android
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Steve PomeroySteve Pomeroy
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C++ compile error: has initializer but incomplete type
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238
You need this include:
#include <sstream>
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Vim - how to run a command immediately when starting vim?
...m' option *SHELL* *COMSPEC* *TERM*
2. Process the arguments
3. Execute Ex commands, from environment variables and/or files *vimrc* *exrc*
4. Load the plugin scripts. *load-plugins*
5. Set 'shellpipe' and 'shellredir'
6. Set 'updatecount' to zero, if "-...
Rounding DateTime objects
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130
Floor
long ticks = date.Ticks / span.Ticks;
return new DateTime( ticks * span.Ticks );
Roun...
App Inventor 2 BLE扩展源码分析 - WriteBytes vs WriteStrings 23字节硬编...
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- BluetoothLE.java（2975行）-- 公开API层
- BluetoothLEint.java（3165行）-- 内部实现层
二、核心发现：23字节硬编码限制
2.1 WriteStrings 的写入路径
位于 BLEWriteOperation.write() 方法第678-690行：
if (mClass == String.class) {
byte[]...