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mysql - how many columns is too many?
... bubakazouba
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answered Sep 24 '09 at 20:45
ChssPly76ChssPly76
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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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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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AndomarAndomar
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The general answer to your question is that it depends. And you get to decide b...