Get count by day for particular coulmn
Hi,
On Fri, Jun 7, 2013 at 7:38 AM, R_Antony <antony.akkara at ge.com> wrote:
here i have a dataframe for eg:- DATETIME COL_A COL_B COL_C COL_D 1/1/2007 0:01 0 3 0 0 1/1/2007 0:02 0 0 3 0 1/1/2007 0:03 0 3 0 0 ....................... ..... ... ... .... 1/2/2007 0 0 3 0 1/2/2007 0:01 0 3 4 0 1/2/2007 0:02 0 3 0 0 ....................... ..... ... ... .... 1/3/2007 0 0 0 0 1/3/2007 0:01 0 0 4 0 1/3/2007 0:02 0 3 0 0 ....................... ..... ... ... .... My requirement what is, i have to get the count for each "day " where COL_B = 3 For eg:- here i need to get like DATETIME COUNT(COL_B=3) ------------ ------------ 1/1/2007 2 1/2/2007 3 1/3/2007 1 ============================= =============================
Since you didn't provide reproducible data (dput() is great for that),
here's an example with fake data:
MyDF <- data.frame(DATETIME = c("1/1/2007", "1/1/2007", "1/1/2007",
"1/2/2007", "1/2/2007", "1/2/2007", "1/3/2007", "1/3/2007",
"1/3/2007"),
COL_A = c(0, 0, 0, 1, 0, 1, 2, 3, 1),
COL_B = c(0, 3, 0, 3, 3, 1, 0, 1, 2),
COL_C = c(1, 2, 3, 1, 2, 3, 1, 2, 3), stringsAsFactors=FALSE)
aggregate(COL_B ~ DATETIME, data=MyDF, FUN=function(x)sum(x == 3))
and this way i tried to get, MyDF[MyDF["DATETIME"]=="1/2/2007"] ---> here this only select the row where DATETIME - column coming as "1/2/2007" - date and not selecting other rows where same date is coming (eg:- 1/1/2007 0:01). And here i need to get the complete records for that particular day, when i give date without giving timestamp.
You omitted a comma: MyDF[MyDF["DATETIME"]=="1/2/2007", ] You might prefer: subset(MyDF, DATETIME == "1/2/2007") Sarah
Sarah Goslee http://www.functionaldiversity.org