On Aug 28, 2010, at 9:15 AM, Stephen Liu wrote:
Hi Gavin,
Lot of thank for your detail explanation.
Just looked at;
?with
?within
Both "Evaluate an Expression in a Data Environment"
Usage: Both;
with(data, expr, ...)
within(data, expr, ...)
Details:
.....
‘within’ is similar, except that it examines the environment after
the evaluation of ‘expr’ and makes the corresponding modifications
to ‘data’ (this may fail in the data frame case if objects are
created which cannot be stored in a data frame), and returns it.
‘within’ can be used as an alternative to ‘transform’.
What does it mean "..... examines the environment after the
evaluation of 'expr'
I take it to mean that the results of expr (applied to "data" and anything else used as arguments) are then used to update "data", but only if possible, i.e., if those results are congruent with the structure of "data". I read that phrase as covering the "if possible" assessment process.
....." Tks B.R. Stephen B.R. Stephen L ----- Original Message ---- From: Gavin Simpson <gavin.simp...@ucl.ac.uk> To: Stephen Liu <sati...@yahoo.com> Cc: "r-help@r-project.org" <r-help@r-project.org> Sent: Sat, August 28, 2010 3:28:34 PM Subject: Re: [R] About plot graphs On Fri, 2010-08-27 at 22:14 -0700, Stephen Liu wrote:Hi Gavin, Thanks for your advice and the examples explaining plotting settings. The steps on your examples work on my test.2) Don't attach() things, you are asking for troubleIf a function has a formula method (which plot does) then use it likethis: plot(Draft_No. ~ Day_of_year, data = Test01)If the function doesn't have a formula method, then wrap it in a with() call:with(Test01, plot(Day_of_year, Draft_No.))No need for attach.Noted and thanks. What will be the problem caused by "attach()"?If you change the underlying data, this is not reflected in the attached copy, because it is just that, a "copy"[1] created at the point at whichyou attached the object. E.g. ## Some data, which we attach dat <- data.frame(A = 1:10, B = letters[1:10]) attach(dat) ## Look at A A ## Change or dat object by altering the A component dat <- within(dat, A <- LETTERS[1:10]) ## Look at A A ## Look at what A really is with(dat, A) Using with() and within() etc have two key advantages over attach: i) only one version of the data/object exists, ii) the intention of code using: with(dat, "do something with A") is much more clear than "do something with A" A could be anything, anywhere. More info is on the ?attach help page. [1] ?attach contains the details of what I mean by "copy"dev.new(height = 6, width = 12) layout(matrix(1:2, ncol = 2)) op <- par(pty = "s") ## this is the important bit plot(runif(100), rnorm(100)) plot(runif(100), rnorm(100), col = "red") par(op) ## now reset the pars layout(1)What is the function of layout(1) ? TksThe opposite of layout(matrix(1:4, ncol = 2)) for example. It ( layout(1) ) says create a layout with a single plotting region. So we use it to reset the current device back tonormal. I find it is good working practice to tidy up after doing plotslike this. In the code above, we change both the layout() and theplotting parameters (via par() ), and the last two lines of code in thatexample reset these changes. GB.R. satimis ----- Original Message ---- From: Gavin Simpson <gavin.simp...@ucl.ac.uk> To: Stephen Liu <sati...@yahoo.com> Cc: "r-help@r-project.org" <r-help@r-project.org> Sent: Fri, August 27, 2010 5:38:40 PM Subject: Re: [R] About plot graphs On Fri, 2010-08-27 at 02:05 -0700, Stephen Liu wrote:Hi Gavin, Thanks for your advice which works for me. (rectangular window) dev.new(height = 6, width = 12) layout(matrix(1:2, nrow=1)) plot(Test01$Day_of_year, Test01$Draft_No.) attach(Test01) plot(Day_of_year,Draft_No.)1) I can't reproduce this; where/what is Test01? But don;t bother sending, see my example below 2) Don't attach() things, you are asking for trouble If a function has a formula method (which plot does) then use it like this: plot(Draft_No. ~ Day_of_year, data = Test01)If the function doesn't have a formula method, then wrap it in a with()call: with(Test01, plot(Day_of_year, Draft_No.)) No need for attach.(rectangular window in vertical position) dev.new(height = 12, width = 4) layout(matrix(1:2, nrow=2)) plot(Test01$Day_of_year, Test01$Draft_No.) plot(Day_of_year,Draft_No.)(height = 12, width = 6) can't work. The graphs plotted are distorted offsquare shape. I must reduce "width = 4" Why? TIABecause you don't appreciate that the dimensions of the device are not the same as the dimensions of the plotting region *on* the device. Most notably, the margins on the device are given by par("mar") for exampleand are not square:par("mar")[1] 5.1 4.1 4.1 2.1 So more space is set aside on the bottom then anywhere else, and the margin on the right is quite small.You have already been provided with an answer that you dismissed becauseyou didn't appear to appreciate what you were being told. Compare this: dev.new(height = 6, width = 12) layout(matrix(1:2, ncol = 2)) plot(runif(100), rnorm(100)) plot(runif(100), rnorm(100), col = "red") layout(1) with this: dev.new(height = 6, width = 12) layout(matrix(1:2, ncol = 2)) op <- par(pty = "s") ## this is the important bit plot(runif(100), rnorm(100)) plot(runif(100), rnorm(100), col = "red") par(op) ## now reset the pars layout(1)So now the regions are square, we have the asymmetric margins like all Rplots and we have drawn this on a device that has ~ appropriate dimensions. If you want to fiddle more with this, then you'll need to make the margins equal, but you don't want to do that really as you need morespace in certain areas to accommodate axis labels and tick labels etc.For the vertical one, this works for me, though note that because of the margins, pty = "s" is making the individual plotting regions smaller torespect the square plotting region you asked for. dev.new(height = 12, width = 6) layout(matrix(1:2, ncol = 1)) op <- par(pty = "s") ## this is the important bit plot(runif(100), rnorm(100)) plot(runif(100), rnorm(100), col = "red") par(op) ## now reset the pars layout(1) This is because you have 5.1 plus 4.1 lines of margin in the verticaldirection per plot (so 18.4 lines in total) versus 4.1 + 2.1 = 6.2 lines of margin in the horizontal direction. So to make the plots square, the horizontal direction is restricted. If we take a bit of space out of thetop/bottom margins, things improve (note I reduce the height as it doesn't fit properly on my monitor): dev.new(height = 10, width = 5) layout(matrix(1:2, ncol = 1)) op <- par(pty = "s", mar = c(4,4,3,2) + 0.1) plot(runif(100), rnorm(100)) plot(runif(100), rnorm(100), col = "red") par(op) ## now reset the pars layout(1) So as we reduce the vertical space required for margins, the square panels start to occupy more and more of the total device. Finally, notice how I provided examples that *you*, *me* and *anyone* else on the list can use to test behaviour/point out problems. Ths is what we call a reproducible example. If you want help without goinground the houses (lots of dead ends), specifying an example like I did (your problem is not with *your* data but with using the R functions, so who cares what the data are?) above allows us very quickly to home in onthe problem you have.Looked at ?dev.new can't resolve. Whether use another command such as; dev.cur() dev.list() dev.next(which = dev.cur()) dev.prev(which = dev.cur()) dev.off(which = dev.cur()) dev.set(which = dev.next()) graphics.off() ?If you had read ?dev.new (and understood it), you would know that thosecommands you list can't possibly help. HTH GB.R. Stephen L ----- Original Message ---- From: Gavin Simpson <gavin.simp...@ucl.ac.uk> To: Stephen Liu <sati...@yahoo.com> Cc: "r-help@r-project.org" <r-help@r-project.org> Sent: Fri, August 27, 2010 4:21:13 PM Subject: Re: [R] About plot graphs On Thu, 2010-08-26 at 21:01 -0700, Stephen Liu wrote:Hi Greg,<snip />windows(width=12, height=6)Error: could not find function "windows"So you aren't on Windows then... Hence why the posting guide asks forsessionInfo() details; sometimes it matters.Anyway, a OS independent way of doing this is to use dev.new() and passalong the arguments you would have provided to the device via e.g. windows(): dev.new(height = 6, width = 12) HTH G?windowsNo documentation for 'windows' in specified packages and libraries: you could try '??windows'window(width=12, height=6)Error in hasTsp(x) : element 1 is empty; the part of the args list of 'attr' being evaluated was: (x, "tsp")?windowwindow {stats} http://stat.ethz.ch/R-manual/R-devel/library/stats/html/window.htmlwindow package:stats R DocumentationTime Windows Description: ‘window’ is a generic function which extracts the subset of the object ‘x’ observed between the times ‘start’ and ‘end’. If afrequency is specified, the series is then re-sampled at the newfrequency.window(layout(matrix(1:2, nrow=1), width=12, height=6))[1] 2 attr(,"tsp") [1] 1 1 1 Still pop up a square window B.R Stephen L ----- Original Message ---- From: Greg Snow <greg.s...@imail.org> To: Stephen Liu <sati...@yahoo.com>; "r-help@r-project.org" <r-help@r-project.org> Sent: Fri, August 27, 2010 10:51:21 AM Subject: RE: [R] About plot graphsWhen you run any graphics command (layout in this case) and there is not acurrent graphics device (more technically only the null device) then adefaultgraphics device is opened, that is what you are seeing. What you need todoinstead is open the device yourself before calling layout. Which devicethatisdepends greatly on information that the posting guide strongly suggeststhatyou provide (another hint). One possibility is:windows(width=12, height=6)Followed by layout and the plotting commands. But whether that will workonyour machine or not is still a bit of a mystery. -- Gregory (Greg) L. Snow Ph.D. Statistical Data Center Intermountain Healthcare greg.s...@imail.org 801.408.8111-----Original Message----- From: r-help-boun...@r-project.org [mailto:r-help-boun...@r- project.org] On Behalf Of Stephen Liu Sent: Thursday, August 26, 2010 8:02 PM To: r-help@r-project.org Subject: Re: [R] About plot graphs Hi Greg, Thanks for your advice.I'm not prepared altering the shape of the graphs to be plotted. WhatI'm trying to do is to pop up a rectangle layout window with following command. The command; layout(matrix(1:2, nrow=1))pop up a square window. What I need is a rectangular window for thegraphs to be plotted. Otherwise the graphs are squeezed changing shape.I looked at ?layout but can't resolve how to make it. Can you help?TIA B.R. Stephen L ----- Original Message ---- From: Greg Snow <greg.s...@imail.org> To: Stephen Liu <sati...@yahoo.com>; "r-help@r-project.org" <r-help@r-project.org> Sent: Fri, August 27, 2010 9:00:01 AM Subject: RE: [R] About plot graphsThere is a graphical parameter that controls whether a plot is squareor takesup the maximum amount of room (rectangle), see ?par and look at theentry for pty.It is possible that you set pty='s' or it may be that the plot methodsets it, without us knowing what type of object Date and Test01$Date are we don't knowwhich method is creating your plot and cannot be much more help (thatis meantas a subtle hint to provide the information requested in the footer ofevery post and the posting guide).Some methods may set pty='s' as default but have an option to changeit. -- Gregory (Greg) L. Snow Ph.D. Statistical Data Center Intermountain Healthcare greg.s...@imail.org 801.408.8111-----Original Message----- From: r-help-boun...@r-project.org [mailto:r-help-boun...@r- project.org] On Behalf Of Stephen Liu Sent: Thursday, August 26, 2010 8:45 AM To: r-help@r-project.org Subject: [R] About plot graphs Hi folks, Following command prints 2 graphs side-by-side:- layout(matrix(1:2, nrow=1)) plot(Date,Input_No.) plot(Test01$Date, Test01$Input_No.) However each is a square graph I need a rectangular layout. Plsadvisehow to make it. TIA B.R. satimis ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-helpPLEASE do read the posting guide http://www.R-project.org/ posting-guide.htmland provide commented, minimal, self-contained, reproducible code.______________________________________________ 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.______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guidehttp://www.R-project.org/posting-guide.htmland provide commented, minimal, self-contained, reproducible code.-- %~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~% Dr. Gavin Simpson [t] +44 (0)20 7679 0522 ECRC, UCL Geography, [f] +44 (0)20 7679 0565 Pearson Building, [e] gavin.simpsonATNOSPAMucl.ac.uk Gower Street, London [w] http://www.ucl.ac.uk/~ucfagls/ UK. WC1E 6BT. [w] http://www.freshwaters.org.uk %~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%-- %~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~% Dr. Gavin Simpson [t] +44 (0)20 7679 0522 ECRC, UCL Geography, [f] +44 (0)20 7679 0565 Pearson Building, [e] gavin.simpsonATNOSPAMucl.ac.uk Gower Street, London [w] http://www.ucl.ac.uk/~ucfagls/ UK. WC1E 6BT. [w] http://www.freshwaters.org.uk %~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~% ______________________________________________ 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.
David Winsemius, MD West Hartford, CT ______________________________________________ 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.
