Search Results

Search found 2 results on 1 pages for 'wahalulu'.

Page 1/1 | 1 

• R equivalent of SELECT DISTINCT on two or more fields/variables

  - by wahalulu

  Say I have a dataframe df with two or more columns, is there an easy way to use unique() or other R function to create a subset of unique combinations of two or more columns? I know I can use sqldf() and write an easy "SELECT DISTINCT var1, var2, ... varN" query, but I am looking for an R way of doing this. It occurred to me to try ftable coerced to a dataframe and use the field names, but I also get the cross tabulations of combinations that don't exist in the dataset: uniques <- as.data.frame(ftable(df$var1, df$var2))

  Read the article

• Writing a script for reading many .csv files with similar filenames

  - by wahalulu

  I have several .csv files with similar filenames except a numeric month (i.e. 03_data.csv, 04_data.csv, 05_data.csv, etc.) that I'd like to read into R. I have two questions: Is there a function in R similar to MATLAB's varname and assignin that will let me create/declare a variable name within a function or loop that will allow me to read the respective .csv file - i.e. 03_data.csv into 03_data data.frame, etc.? I want to write a quick loop to do this because the filenames are similar. As an alternative, is it better to create one dataframe with the first file and then append the rest using a for loop? How would I do that?

  Read the article

1