Data science: R meta programing
14 Nov 2015Load CSV files into dynamically named dataframe objects
I had the option of statically defining a R variable and loading the corresponding CSV file into it. For example,
temperature <- read.csv("./data_files/temperature.csv")
This isn’t pragmatic since we have to update variable and filename according to changing data files. The seeming better option is to search for all CSV files in a directory, and dynamically load their respective data into dynamically assigned variable names. For example,
# get all files in the data_files directory
csv_files <- Sys.glob("./data_files/*.csv")
# loop over files
for (file in csv_files) {
# load the file contents into R
df = read.csv(file)
# convert "data_files/temperature.csv" to "temperature" for the variable name
full_path = strsplit(file, "/")
paths = full_path[[1]]
file_name = paths[length(paths)]
parts = strsplit(file_name, ".", fixed = TRUE)
var_name = parts[[1]][1]
# dynamically assign value to to R variaible.
# ie, "temperature" is a R data.frame
assign(var_name, df)
}