Summary tables of large datasets including character and numerical variables
On Dec 26, 2011, at 5:44 AM, sparandekar wrote:
Hello ! I am attempting to switch from being a long time SAS user to R, and would really appreciate a bit of help ! The first thing I do in getting a large dataset (thousands of obervations and hundreds of variables) is to run a SAS command PROC CONTENTS VARNUM command - this provides me a table with the name of each variable, its type and length; then I run a PROC MEANS - for numerical variables it gives me a table with the number of non-missing values, min, max, mean and std. dev. My data usually has errors and this first step helps me to spot the errors and 'clean' the dataset. The 'summary' function in R and other function as part of Hmisc or Psych package do not work for me. How can I get a table from an R data.frame that has the following structure (header row and example). Rowname Character/Integer Length Non-Missing Minimum Maximum Mean SD HHID Integer 12 32,344 114455007701 514756007812 2.345 x 10^10 1.456 x 10^10 Head Character 38 24,566 - - - -
I generally use ( in order of increasing information content and increasing length of output): names(dfrm) str(dfrm) Hmisc::describe(dfrm) (Several other packages have their own versions of 'describe'.)
David Winsemius, MD West Hartford, CT