> -----Original Message----- > From: r-help-boun...@r-project.org > [mailto:r-help-boun...@r-project.org] On Behalf Of Mark Knecht > Sent: Sunday, June 28, 2009 7:32 PM > To: Gabor Grothendieck > Cc: r-help@r-project.org > Subject: Re: [R] newbie - read.csv creates a (data.frame, > table, array, matrix, ...) and plotting one column > > Thank you VERY much Gabor. I learned a LOT from this little post: > > 1) I can read/modify/write data in the array using the sub function > 2) I can address columns using $COLUMN_HEADER > 3) I can do an XY plot using X ~ Y > > Brilliant! Thanks! > > Small result PDF attached. > > Cheers, > Mark > > On Sun, Jun 28, 2009 at 7:04 PM, Gabor > Grothendieck<ggrothendi...@gmail.com> wrote: > > Try removing double quotes and commas from T1$EQUITY > > and then convert it to numeric: > > > > T1$EQUITY <- as.numeric(sub('[",]', '', T1$EQUITY)) > > plot(EQUITY ~ TRADE, T1) > > > > > > On Sun, Jun 28, 2009 at 9:14 PM, Mark > Knecht<markkne...@gmail.com> wrote: > >> On Sun, Jun 28, 2009 at 4:02 PM, Mark > Knecht<markkne...@gmail.com> wrote: > >>> Hi all, > >>> Newbie alert. > >> <SNIP> > >>> > >>> The second question is about plotting one column from data set. > >>> I've used read.csv to read in somethign called PFA_VWAP. > row.names, > >>> names and dim all return sensible values. The command > >>> PFA_VWAP_Equity<-PFA_VWAP[,10] seems to load the new > variable with the > >>> right data for the equity curve, but how do I plot it? > >>> plot(PFA_VWAP_Equity) gives me a chart that doesn't make > sense to me. > >>> Note however that the original values that make up column 10 were > >>> surrounded by quotes so I'm not sure how to tell what > sort of data R > >>> thinks is in column 10. Is it numeric or text? I think > it's integer > >>> from the last command. > >> <SNIP> > >> > >> So I've tried to boil this down to the something simple > others can try > >> and duplicate my confusion, or just see what's going on from this > >> post. > >> > >> Basically I'm trying to get a handle on the difference > between a list > >> and an array, and how to take my data read with read.csv > and plot it > >> on a scatter chart. > >> > >> 1) Here's a small portion of one of my data files. I put > this at C:\Test1.csv > >> > >> PORTFOLIO EQUITY TABLE > >> TRADE,MARK-SYS,DATE/TIME,PL/SIZE,PS METHOD,POS SIZE,POS > >> PL,DRAWDOWN,DRAWDOWN(%),EQUITY > >> 1,1,1/9/2004 1:11:00 PM,-146.00,As > Given,1,-146.00,146.00,1.460,"9,854.00" > >> 2,1,1/12/2004 1:11:00 PM,874.00,As > Given,1,874.00,0.00,0,"10,728.00" > >> 3,1,1/13/2004 1:11:00 PM,224.00,As > Given,1,224.00,0.00,0,"10,952.00" > >> 4,1,1/28/2004 12:28:00 PM,-626.00,As > Given,1,-626.00,626.00,5.716,"10,326.00" > >> 5,1,2/9/2004 1:11:00 PM,64.00,As > Given,1,64.00,562.00,5.131,"10,390.00" > >> 6,1,2/13/2004 1:11:00 PM,-116.00,As > Given,1,-116.00,678.00,6.191,"10,274.00" > >> 7,1,2/20/2004 1:11:00 PM,364.00,As > Given,1,364.00,314.00,2.867,"10,638.00" > >> 8,1,2/23/2004 11:23:00 AM,-626.00,As > Given,1,-626.00,940.00,8.583,"10,012.00" > >> 9,1,2/24/2004 1:11:00 PM,114.00,As > Given,1,114.00,826.00,7.542,"10,126.00" > >> 10,1,2/25/2004 1:11:00 PM,444.00,As > Given,1,444.00,382.00,3.488,"10,570.00" > >> > >> (In case of line breakage everything from TRADE to EQUITY > is on line 2 > >> and there are 10 lines that follow making 12 lines total.) > >> > >> 2) I read this into R creating T1 using the command > >> > >> T1<-read.csv("C:\\Test1.csv",skip=1,header=TRUE) > >> > >> 3) If I type T1 and hit return then I see the data. > >> > >> 4) dim(T1) says 10 10 which is correct. > >> > >> 5) I can read the two columns I want to use to create the > scatter plot using: > >> > >>> T1[,1] > >> [1] 1 2 3 4 5 6 7 8 9 10 > >>> T1[,10] > >> [1] 9,854.00 10,728.00 10,952.00 10,326.00 10,390.00 10,274.00 > >> 10,638.00 10,012.00 10,126.00 10,570.00 > >> Levels: 10,012.00 10,126.00 10,274.00 10,326.00 10,390.00 10,570.00 > >> 10,638.00 10,728.00 10,952.00 9,854.00 > >>> > >> > >> Now, here's the confusion. plot(T1[,1],T1[,10]) creates a plot, but > >> the range on both X & Y is 1-10. I want 1-10 on the X axis but need > >> the values in the first line of the T1[,10] return as the Y axis. > >> > >> How can I create that scatter plot? > >> > >> Thanks, > >> Mark > >> > >> ______________________________________________ > >> R-help@r-project.org mailing list > >> https://stat.ethz.ch/mailman/listinfo/r-help > >> PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > >> and provide commented, minimal, self-contained, reproducible code. > >> > > >
Mark, I'm glad you are making progress. However, you are going to want to continue reading up on matrices, arrays, lists, and data frames. What read.csv creates is a data frame which is not the same as a matrix or an array. As you move forward you will want to keep these structues separate in your mind. Best of luck, Dan Daniel Nordlund Bothell, WA USA ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
