Drop unused factor levels in a subsetted data frame

Drop unused factor levels in a subsetted data frame

r dataframe r-factor r-faq

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Confusion between factor levels and factor labels

r r-factor r-faq

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Factors in R: more than an annoyance?

r language-design internals r-factor

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Coerce multiple columns to factors at once

r dataframe r-factor

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Why use as.factor() instead of just factor()

r r-factor

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Imported a csv-dataset to R but the values becomes factors

r r-factor read.csv

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Plotting with ggplot2: "Error: Discrete value supplied to continuous scale" on categorical y-axis

r ggplot2 scale categorical-data r-factor

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Unseen factor levels when appending new records with unseen string values to a dataframe, cause Warning and result in NA

r dataframe append r-factor

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How to concatenate factors, without them being converted to integer level?

r concatenation r-factor

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How do I convert certain columns of a data frame to become factors? [duplicate]

r numeric r-factor

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Sort a factor based on value in one or more other columns

r r-factor

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Concatenate rows of a data frame

r vector concatenation paste r-factor

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Colouring plot by factor in R

r colors plot r-factor

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Change stringsAsFactors settings for data.frame

r dataframe default options r-factor

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Converting a factor to numeric without losing information R (as.numeric() doesn't seem to work) [duplicate]

r r-factor

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