Simple time series questions

I'm sure this is a really simple problem, but I've spent hours digging and
I keep running into roadblocks.

I'm trying to get a simple chart with three time series.  Similar to the
attached example 
http://www.nabble.com/file/p25398419/Excel%2Bchart%2Bexample.pdf
Excel+chart+example.pdf , something that was quite easy to do in Excel,
except that I need a log y-axis: something that R can do and Excel can't.

The data is in the attached CSV file 
http://www.nabble.com/file/p25398419/test%2Bchart%2Bdata.csv
test+chart+data.csv .  I can read it in OK, and create separate charts:

testdata<- read.table("C:\\Files\\test chart data.csv", head = T, sep =
",",na.strings = "na")
test_date = as.Date(testdata$Date,"%d-%m-%y")
test_data_model = testdata$Model
test_date_baseA = testdata$BaseDataA
test_date_baseB = testdata$BaseDataB
plot(test_date, test_data_model,type='l',log="y")
plot(test_date, test_data_baseA,type='l',log="y")
plot(test_date, test_data_baseB,type='l',log="y")
grid()

(Clearly at this point, each chart over-writes the previous one.)

Next I try to get them onto a single chart, sharing the same y-axis.  I'm
sure I haven't done this very elegantly, but here goes:

frame_model = data.frame(a=test_date,b=test_data_model)
frame_A = data.frame(a=test_date,b=test_data_baseA)
frame_B = data.frame(a=test_date,b=test_data_baseB)
ts_model = ts(frame_model$b)
ts_a = ts(frame_A$b)
ts_b = ts(frame_B$b)
ts.plot(ts_model,ts_a,ts_b,col=c("blue","red","green"),log="y")

The problem is that I no longer have the date along the y-axis.  How can I
get that back?

Finally, when I plot the separate time series, the grid() function
geneates a grid where the vertical lines are not lined up with the year
tick marks.  I interpreted the topic help as saying that by default they
would match the tick marks.  How can I achieve that?

Thanks for any suggestions,

Guy Green

This script worked for me. Be sure to put in your correct link.

  link <- "C:\\R_Home\\Charts & Graphs Blog\\R_Chart_Doc\\text_data.csv"
  testdata<- read.table(link, head = T, sep = ",",na.strings = "na")
  test_date = as.Date(testdata$Date,"%d-%m-%y") 

  plot(test_date, testdata$Model, type="l", log="y") 
  points(test_date, testdata$BaseDataA, type = "l", col = "red")
  points(test_date, testdata$BaseDataB, type = "l", col = "blue")

You add 2nd and 3rd series with points command

Hope this helps.

Kelly

 http://chartsgraphs.wordpress.com http://chartsgraphs.wordpress.com 

Thanks - that works great.

Do you have any suggestions about the grid() problem - i.e. that the
vertical gridlines do not line up with the x-axis tickmarks (which are
years)?

I can't see on what basis the vertical gridlines are being positioned, but
it doesn't look good that they are not lined up with anything.

Thanks,

Guy


DKOD wrote:

This script worked for me. Be sure to put in your correct link.

  link <- "C:\\R_Home\\Charts & Graphs Blog\\R_Chart_Doc\\text_data.csv"
  testdata<- read.table(link, head = T, sep = ",",na.strings = "na")
  test_date = as.Date(testdata$Date,"%d-%m-%y") 

  plot(test_date, testdata$Model, type="l", log="y") 
  points(test_date, testdata$BaseDataA, type = "l", col = "red")
  points(test_date, testdata$BaseDataB, type = "l", col = "blue")

You add 2nd and 3rd series with points command

Hope this helps.

Kelly

 http://chartsgraphs.wordpress.com http://chartsgraphs.wordpress.com 

Try this script. I converted test_date to numeric decimal year

link <- "C:\\R_Home\\Charts & Graphs Blog\\R_Chart_Doc\\text_data.csv"
?testdata<- read.table(link, head = T, sep = ",",na.strings = "na")
?test_date = as.Date(testdata$Date,"%d-%m-%y")

# Convert dates to decimal year
?my_yr <- as.numeric(format(test_date,format="%Y"))
?my_mo <- as.numeric(format(test_date, format="%m"))
?dec_yr <- my_yr + (my_mo+0.5)/12

?plot(dec_yr, testdata$Model, type="l", log="y", xaxs="i", yaxs="i",
? ? axes=T, xlim = c(2003, 2008))
?points(dec_yr, testdata$BaseDataA, type = "l", col = "red")
?points(dec_yr, testdata$BaseDataB, type = "l", col = "blue")
?grid( col="grey",lty=1)
?box()

Kelly

http://chartsgraphs.wordpress.com http://chartsgraphs.wordpress.com


gug wrote:

Thanks - that works great.

Do you have any suggestions about the grid() problem - i.e. that the
vertical gridlines do not line up with the x-axis tickmarks (which are
years)?

I can't see on what basis the vertical gridlines are being positioned, but
it doesn't look good that they are not lined up with anything.

Thanks,

Guy


DKOD wrote:

This script worked for me. Be sure to put in your correct link.

? link <- "C:\\R_Home\\Charts & Graphs Blog\\R_Chart_Doc\\text_data.csv"
? testdata<- read.table(link, head = T, sep = ",",na.strings = "na")
? test_date = as.Date(testdata$Date,"%d-%m-%y")

? plot(test_date, testdata$Model, type="l", log="y")
? points(test_date, testdata$BaseDataA, type = "l", col = "red")
? points(test_date, testdata$BaseDataB, type = "l", col = "blue")

You add 2nd and 3rd series with points command

Hope this helps.

Kelly

?http://chartsgraphs.wordpress.com http://chartsgraphs.wordpress.com

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