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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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Rounding DateTime objects
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130
Floor
long ticks = date.Ticks / span.Ticks;
return new DateTime( ticks * span.Ticks );
Roun...
C++ compile error: has initializer but incomplete type
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238
You need this include:
#include <sstream>
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How do I specify “close existing connections” in sql script
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AndomarAndomar
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8
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Should I URL-encode POST data?
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138
General Answer
The general answer to your question is that it depends. And you get to decide b...
codestyle; put javadoc before or after annotation?
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193
Before the annotation, since the annotation is code that "belongs" to the class.
See examples wi...
express throws error as `body-parser deprecated undefined extended`
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mscdexmscdex
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How to disable action bar permanently
...Holo.Light and want to use the Theme.Holo.Light.NoActionBar variant on pre 3.2 devices you can add this to your styles.xml:
<style name="NoActionBar" parent="@android:style/Theme.Holo.Light">
<item name="android:windowActionBar">false</item>
<item name="android:windowNo...