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Help Reformatting a Data table

2 messages · Michael E. Steiper, Dennis Murphy

Michael E. Steiper
# 
Hi, I am a relative newbie to R, so thanks in advance for the patience.

I am interesting in changing a table with year data into a format that
is friendlier for making bar charts. I currently have a table with the
same year appearing a number of times as separate rows.  I want to
change this so that each row is equivalent to a particular year.

Here is an example of my current format:

TAX	YEAR	NUMBER
A	2000	          2
A	2001		  2
A	2002	          3
A	2003	           1
B	2000	          3
B	2001	          4
B	2002	          3
B	2004	           2

A<-data.frame(c("A", "A", "A", "A", "B","B","B","B"),
c(2000,2001,2002,2003,2000,2001,2002,2004), c(2,2,3,1,3,4,3,2))
colnames(A) = c("TAX", "YEAR", "NUMBER")

I want to Change this to the following:

YEAR	A	B
2000	       2	3
2001	       	2	4
2002	       3	3
2003	       1	0
2004    	0	2

Any help would be appreciated!

Of course, while I am posting, I'll also ask for any tips for creating
a barchart with the X axis being "YEAR".

Thanks for the time

Mike
Dennis Murphy
# 
Here's one way to do it using the reshape package:

library('reshape')
cast(A, YEAR ~ TAX, value = 'NUMBER', fill = 0)
  YEAR A B
1 2000 2 3
2 2001 2 4
3 2002 3 3
4 2003 1 0
5 2004 0 2

HTH,
Dennis

On Tue, Oct 18, 2011 at 7:51 PM, Michael E. Steiper
<michaelsteiper at gmail.com> wrote: