R vectors, data frames, factors, apply family, tidyverse verbs with dplyr and ggplot2 grammar of graphics.
40 cards · basic cards · AI-written, checked twice. Edit anything.
- What does c() do in R?
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Combines values into a vector- How do you get the length of a vector?
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Use length()- What does rep(3, 5) create?
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A vector with 3 repeated 5 times- What does seq(1, 10, by=2) create?
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A sequence from 1 to 10 incrementing by 2- How do you access the third element of vector x?
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x[3]- What are the four main vector types in R?
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numeric, character, logical, complex- What does as.numeric('42') do?
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Converts the string to the number 42- What is the purpose of is.numeric()?
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Tests whether an object is numeric, returning TRUE or FALSE- How do you create a data frame in R?
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Use data.frame() function- What does nrow(df) return?
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The number of rows in data frame df- What does ncol(df) return?
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The number of columns in data frame df- How do you access the column named 'age' from df?
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df$age or df[['age']]- What does head(df) show by default?
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The first 6 rows of df- What does tail(df, 10) show?
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The last 10 rows of df- How do you add a new column to df?
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df$newcol <- values or df[['newcol']] <- values
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