Hi, I have a three vectors: month, year, and partial pressure of carbon dioxide for 2914 observations. I am trying to use a program to analyze the seasonality of the data, but the program requires that the data be in a 2914x2 (2914 rows, 2 columns) matrix such that column one is the year and month (i.e. February 2012 would be 20121 and June 1985 would be 19856) and column 2 is the partial pressure of carbon dioxide. I've tried countless times to get the data in this format but no matter what I do when I concatenate it forms a 2914x3 matrix. Is there a way to actually concatenate the year and month vectors to get in the format "yearmonth" like 20121 or 19856? Thanks so much!