col_types
You can also specify which types the columns in your imported data frame should have. You can do this with col_types. If set to NULL, the default, functions from the readr package will try to find the correct types themselves. You can manually set the types with a string, where each character denotes the class of the column: character, double, integer and logical. _ skips the column as a whole.
potatoes.txt (view), a flat file with tab-delimited records and without column names, is again available in your workspace.
This is a part of the course
“Introduction to Importing Data in R”
Exercise instructions
- In the second
read_tsv()call, edit thecol_typesargument to import all columns as characters (c). Store the resulting data frame inpotatoes_char. - Print out the structure of
potatoes_charand verify whether all column types arechr, short forcharacter.
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
# Column names
properties <- c("area", "temp", "size", "storage", "method",
"texture", "flavor", "moistness")
# Import all data, but force all columns to be character: potatoes_char
potatoes_char <- read_tsv("potatoes.txt", col_types = "iiiiiddd", col_names = properties)
# Print out structure of potatoes_char
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