R: how to rotate label of secondary Y axis?? {base} - r

I've created secondary Y axis, and I've put a label there as well using mtext. However, I can't figure out how to rotate my secondary Y label in the way to face a plot - like my red Y2 label ?
My dummy data, adopted from : http://robjhyndman.com/hyndsight/r-graph-with-two-y-axes/
x <- 1:5
y1 <- rnorm(5)
y2 <- rnorm(5,20)
par(mar=c(5,4,4,5)+.1)
plot(x,y1,type="l",col="red")
par(new=TRUE)
plot(x, y2,,type="l",col="blue",xaxt="n",yaxt="n",xlab="",ylab="")
axis(4)
mtext("y2",side=4,line=3)
legend("topleft",col=c("red","blue"),lty=1,legend=c("y1","y2"))
result:
I've tried srt = ..., of las = ..., neither of them does work.
I don't necessary need to use mtext, is there please another simple solution ?
Thank you !

Use text instead of mtext:
set.seed(1)
x <- 1:5
y1 <- rnorm(5)
y2 <- rnorm(5,20)
par(mar=c(5,4,4,5)+.1)
plot(x,y1,type="l",col="red")
par(new=TRUE)
plot(x, y2,,type="l",col="blue",xaxt="n",yaxt="n",xlab="",ylab="")
axis(4)
text(par("usr")[2]*1.11,mean(par("usr")[3:4]), "y2", srt = -90, xpd = TRUE, pos = 4)
legend("topleft",col=c("red","blue"),lty=1,legend=c("y1","y2"))
(via)

Related

How to plot a surface in rgl plot3d

So I have this code that produces the exact surface
f = function(x, y){
z = ((x^2)+(3*y^2))*exp(-(x^2)-(y^2))
}
plot3d(f, col = colorRampPalette(c("blue", "white")),
xlab = "X", ylab = "Y", zlab = "Z",
xlim = c(-3, 3), ylim = c(-3, 3),
aspect = c(1, 1, 0.5))
Giving the following plot:
Now I have some code that does a random walk metropolis algorithm to reproduce the above image. I think it works as if I do another plot of these calculated values I get the next image with 500 points. Here is the code
open3d()
plot3d(x0, y0, f(x0, y0), type = "p")
Which gives the following plot:
I know it's hard looking at this still image but being able to rotate the sampling is working.
Now here is my question: How can I use plot3d() so that I can have a surface that connects all these points and gives a more jagged representation of the exact plot? Or how can I have each point in the z axis as a bar from the xy plane? I just want something more 3 dimensional than points and I can't find how to do this.
Thanks for your help
You can do this by triangulating the surface. You don't give us your actual data, but I can create some similar data using
f = function(x, y){
z = ((x^2)+(3*y^2))*exp(-(x^2)-(y^2))
}
x <- runif(500, -3, 3)
y <- runif(500, -3, 3)
z <- f(x, y)
Then the plotting is done using the method in ?persp3d.deldir:
library(deldir)
library(rgl)
col <- colorRampPalette(c("blue", "white"))(20)[1 + round(19*(z - min(z))/diff(range(z)))]
dxyz <- deldir::deldir(x, y, z = z, suppressMsge = TRUE)
persp3d(dxyz, col = col, front = "lines", back = "lines")
This might need some cosmetic fixes, e.g.
aspect3d(2, 2, 1)
After some rotation, this gives me the following plot:
I'm not sure to understand what you want. If my understanding is correct, here is a solution. Define a parametric representation of your surface:
fx <- function(u,v) u
fy <- function(u,v) v
fz <- function(u,v){
((u^2)+(3*v^2))*exp(-(u^2)-(v^2))
}
Let's say you have these points:
x0 <- seq(-3, 3, length.out = 20)
y0 <- seq(-3, 3, length.out = 20)
Then you can use the function parametric3d of the misc3d package, with the option fill=FALSE to get a wireframe:
library(misc3d)
parametric3d(fx, fy, fz, u=x0, v=y0,
color="blue", fill = FALSE)
Is it what you want?
To get some vertical bars, use the function segments3d of rgl:
i <- 8
bar <- rbind(c(x0[i],y0[i],0),c(x0[i],y0[i],f(x0[i],y0[i])))
segments3d(bar, color="red")
Here is a plot with only 50 points using my original code.
When I then apply what was said by Stéphane Laurent I then get this plot which feels too accurate when given the actual points I have
Perhaps you need to explain to me what is actually happening in the function parametric3d

Using UTF-8 codes for use in intToUtf8() in R?

I'm trying to use UTF-8 code to put a symbol in some text in an R figure. If I wanted a black circle, I could use the code intToUtf8(9679). Where can I find a database that lists the values for other symbols? I want to find the code to create a red circle (i.e., pch=16, col="red"), but I can't find a list of what all of the unicode values are for specific symbols.
# example R code
x <- 1:10
y1 <- rnorm(10, x*2, 0.5)
y2 <- rnorm(10, x, 0.5)
plot(x, y1, xlab='x-value', ylab='', pch=16)
points(x, y2, pch=16, col='red')
mtext(paste0('value for y1 (', intToUtf8(9679), ') and y2 (', intToUtf8(9679), ')'), side=2, line=2)
# except that I want the second black circle in the axis label to be a red circle
Thank you for your help,
Mikey
Here is the solution I ended up using. It's not the most efficient, but it works:
x <- 1:10
y1 <- rnorm(10, x*2, 0.5)
y2 <- rnorm(10, x, 0.5)
plot(x, y1, xlab='x-value', ylab='', pch=16)
points(x, y2, pch=16, col='red')
mtext('value for y1 (\u25CF) and y2 ( )', side=2, line=2)
mtext(' \u25CF', side=2, line=2, col='red')
# alternatively, the following would also work in place of line 6
mtext(paste0('value for y1 (', intToUtf8(9679),' and y2 ( )'), side=2, line=2)
If you want to find more unicode character information for your specific symbol, you can look here.
Thank you lukeA for your help with this.

Boxplots in R. Y interval (tick marks) and grid

I have the following code:
boxplot(c(Scatt_nocoop, Scatt_coop),
xlab="Scattered", col=c("red","red"),
names=c("Non-cooperative"," Cooperative "),
ylim = c(0,2.5))
I am trying to add tick marks in the Y axis every 0.1, to then add a grid.
Also, I would like to get the Y axis in percentage rather than with numbers.
Thank you!
not sure what your data looks like, but I guess you want something like this:
x1 <- rnorm(100) + 2
x2 <- rnorm(100) + 2
df <- data.frame(x = c(x1, x2), g = rep(1:2,each=100))
boxplot(df$x~df$g,
xlab="Scattered", col=c("red","red"),
names=c("Non-cooperative"," Cooperative "),
ylim = c(0,5),
yaxt = "n")
add ticks and (manual) grid lines
axis(2, at = seq(0,5,0.1))
lapply(seq(0,5,0.1), function(x) abline(a = x,b = 0))

Plotting two Poisson processes on one plot

I have two Poisson processes:
n <- 100
x <- seq(0, 10, length = 1000)
y1 <- cumsum(rpois(1000, 1 / n))
y2 <- -cumsum(rpois(1000, 1 / n))
I would like to plot them in one plot and expect that y1 lies above x-axis and y2 lies below x-axis. I tried the following code:
plot(x, y1)
par(new = TRUE)
plot(x, y2, col = "red",
axes = FALSE,
xlab = '', ylab = '',
xlim = c(0, 10), ylim = c(min(y2), max(y1)))
but it did not work. Can someone please tell me how to fix this? (I am working with R for my code)
Many thanks in advance
How about
plot(x,y1, ylim=range(y1,y2), type="l")
lines(x, y2, col="red")
I would suggest trying to avoid multiple calls to plot with par(new=TRUE). That is usually very messy. Here we use lines() to add to an existing plot. The only catch is that the x and y limits won't change based on the new data, so we use ylim in the first plot() call to set a range appropriate for all the data.
Or if you don't want to worry about limits (like MrFlick mentioned) or the number of lines, you could also tide up your data and using melt and ggplot
df <- data.frame(x, y1, y2)
library(reshape2)
library(ggplot2)
mdf <- melt(df, "x")
ggplot(mdf, aes(x, value, color = variable)) +
geom_line()

Controlling z labels in contourplot

I am trying to control how many z labels should be written in my contour plot plotted with contourplot() from the lattice library.
I have 30 contour lines but I only want the first 5 to be labelled. I tried a bunch of things like
contourplot(z ~ z+y, data=d3, cuts=30, font=3, xlab="x axis", ylab="y axis", scales=list(at=seq(2,10,by=2)))
contourplot(z ~ z+y, data=d3, cuts=30, font=3, xlab="x axis", ylab="y axis", at=seq(2,10,by=2))
but nothing works.
Also, is it possible to plot two contourplot() on the same graph? I tried
contourplot(z ~ z+y, data=d3, cuts=30)
par(new=T)
contourplot(z ~ z+y, data=d3, cuts=20)
but it's not working.
Thanks!
Here is my take:
library(lattice)
x <- rep(seq(-1.5,1.5,length=50),50)
y <- rep(seq(-1.5,1.5,length=50),rep(50,50))
z <- exp(-(x^2+y^2+x*y))
# here is default plot
lp1 <- contourplot(z~x*y)
# here is an enhanced one
my.panel <- function(at, labels, ...) {
# draw odd and even contour lines with or without labels
panel.contourplot(..., at=at[seq(1, length(at), 2)], col="blue", lty=2)
panel.contourplot(..., at=at[seq(2, length(at), 2)], col="red",
labels=as.character(at[seq(2, length(at), 2)]))
}
lp2 <- contourplot(z~x*y, panel=my.panel, at=seq(0.2, 0.8, by=0.2))
lp3 <- update(lp2, at=seq(0.2,0.8,by=0.1))
lp4 <- update(lp3, lwd=2, label.style="align")
library(gridExtra)
grid.arrange(lp1, lp2, lp3, lp4)
You can adapt the custom panel function to best suit your needs (e.g. other scale for leveling the z-axis, color, etc.).
You can specify the labels as a character vector argument and set the last values with rep("", 5), so perhaps for the example you offered on an earlier question about contour
x = seq(0, 10, by = 0.5)
y = seq(0, 10, by = 0.5)
z <- outer(x, y)
d3 <- expand.grid(x=x,y=y); d3$z <- as.vector(z)
contourplot(z~x+y, data=d3)
# labeled '5'-'90'
contourplot(z~x+y, data=d3,
at=seq(5,90, by=5),
labels=c(seq(5,25, by=5),rep("", 16) ),
main="Labels only at the first 5 contour lines")
# contourplot seems to ignore 'extra' labels
# c() will coerce the 'numeric' elements to 'character' if any others are 'character'
?contourplot # and follow the link in the info about labels to ?panel.levelplot

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