Hello all,
I have a situation where I'd like to plot points from multiple groups of
data in one plot. I'd like each group's points to be colored a
different
color. I've seen people comment on how you can alternate colors by
providing a range of colors and then it will loop through each color as it
plots individual points. However, that just goes by individual points and
not by group.
Next I thought if, for example, I had 2 groups, I could make a 2 color
vector. Then I could merge the data from my two groups alternating into an
X and Y vector, but that doesn't work either because the 2 groups may not
have equal numbers of members. For example
-------------------------------
Group1_Xdata <- c(1,2,3,4,5)
Group2_Xdata <- c(10,20,30,40,50)
Colors <- c("red","blue")
Merged_XData <- c(1,10,2,10,3,30,4,40,5,50)
(SAME MERGE FOR Y DATA)
-----------------------------
That would work to make group1 red and group2 blue, but if Group 2 had 6
members instead of 5, then the 6th member would come out red.
Any thoughts? Also, I want to be able to code this generically enough that
I can have any number of groups and colors.
Best Regards,
Dave
Hello again,
I think this will help me:
http://www.math.montana.edu/Rweb/Rhelp/points.html
I'll email again if it doesn't.
Dave
-----Original Message-----
From: David Thibault
Sent: Thursday, February 26, 2004 11:13 AM
To: R-help at r-project.org
Subject: Help with multicolored points in one plot
Hello all,
I have a situation where I'd like to plot points from multiple groups of
data in one plot. I'd like each group's points to be colored a
different
color. I've seen people comment on how you can alternate colors by
providing a range of colors and then it will loop through each color as it
plots individual points. However, that just goes by individual points and
not by group.
Next I thought if, for example, I had 2 groups, I could make a 2 color
vector. Then I could merge the data from my two groups alternating into an
X and Y vector, but that doesn't work either because the 2 groups may not
have equal numbers of members. For example
-------------------------------
Group1_Xdata <- c(1,2,3,4,5)
Group2_Xdata <- c(10,20,30,40,50)
Colors <- c("red","blue")
Merged_XData <- c(1,10,2,10,3,30,4,40,5,50)
(SAME MERGE FOR Y DATA)
-----------------------------
That would work to make group1 red and group2 blue, but if Group 2 had 6
members instead of 5, then the 6th member would come out red.
Any thoughts? Also, I want to be able to code this generically enough that
I can have any number of groups and colors.
Best Regards,
Dave
On Thu, 26 Feb 2004, David Thibault wrote:> Hello all, > > I have a situation where I'd like to plot points from multiple groups of > data in one plot. I'd like each group's points to be colored a different > color. I've seen people comment on how you can alternate colors by > providing a range of colors and then it will loop through each color as it > plots individual points. However, that just goes by individual points and > not by group. >Concatenate the groups into a single x vector and y vector, together with a vector of group identifiers (eg 1,1,1,1,1,2,2,2,2,2,2,2,3,3), then plot(y~x, col=group) or to get more control prettycolors<- c("forestgreen","goldenrod","sienna") plot(y~x, col=prettycolors[group]) There are examples in demo(graphics). -thomas
On Thursday 26 February 2004 10:13, David Thibault wrote:> Hello all, > > I have a situation where I'd like to plot points from multiple groups of > data in one plot. I'd like each group's points to be colored a > different color. I've seen people comment on how you can alternate > colors by providing a range of colors and then it will loop through each > color as it plots individual points. However, that just goes by > individual points and not by group. > > Next I thought if, for example, I had 2 groups, I could make a 2 color > vector. Then I could merge the data from my two groups alternating into > an X and Y vector, but that doesn't work either because the 2 groups may > not have equal numbers of members. For example > ------------------------------- > Group1_Xdata <- c(1,2,3,4,5) > Group2_Xdata <- c(10,20,30,40,50) > > Colors <- c("red","blue") > Merged_XData <- c(1,10,2,10,3,30,4,40,5,50) > > (SAME MERGE FOR Y DATA) > ----------------------------- > That would work to make group1 red and group2 blue, but if Group 2 had 6 > members instead of 5, then the 6th member would come out red. > > Any thoughts? Also, I want to be able to code this generically enough > that I can have any number of groups and colors.Trellis graphics (using the lattice package in R) has a fairly systematic approach for doing this. See example(xyplot) for some examples. For your data, a possible usage could be: x <- c(Group1_Xdata, Group2_Xdata) y <- c(Group1_Ydata, Group2_Ydata) g <- c(rep(1, length(Group1_Xdata)), rep(2, length(Group2_Xdata))) xyplot(y ~ x, groups = g) or if you want to control the colors xyplot(y ~ x, groups = g, col = c("red", "blue")) With base graphics, something similar could be achieved with plot(x, y, col = c("red", "blue")[g]) lattice is more systematic in the sense that it has globally modifiable settings to control various graphical parameters (not only color) used to distinguish between groups, with reasonable defaults. Hth, Deepayan