Rank() Over Partition by in R – Easiest Method to Follow

Topbullets.comCurrently I am working on R, SAS and SQL languages and recently I came across a new problem. I want to rank my data set on particular columns. Ranking on a single column is very easy but when it comes for multiple columns, it becomes little tough. I Googled my problem, searched for entire day but could not find any satisfactory solution.
Finally I made my own way and it really worked. Here is the solution to this problem. Continue reading