plot level, velocity, acceleration with one x axis

On 5/29/23 2:37 AM, Eric Berger wrote:

How about this:

a <- cbind(AirPassengers, diff(log(AirPassengers)),
diff(diff(log(AirPassengers))))
colnames(a)[2:3] <- c("percent increase", "acceleration")
plot(a, xlab="year", main="AirPassengers")

          My real problem is more difficult:  I'm analyzing CO2 data from Our
World in Data (https://ourworldindata.org/co2-emissions), and I need to
plot the CO2 data on a log scale but velocity and acceleration on linear
scales.  The following is comparable:


str(DAX <- EuStockMarkets[, 'DAX'])
str(DAX. <- cbind(DAX, diff(log(DAX)),
                   diff(diff(log(DAX)))))
colnames(DAX.)[2:3] <- c('vel', 'accel')
plot(DAX.)


          I want the first of the three panels to plot on the log scale, but
the other two on linear scales.  The obvious attempt does not work:


plot(DAX., log=c('y', '', ''))
#Error in length(log) && log != "" :
#  'length = 3' in coercion to 'logical(1)'


          Trying to construct my own axes isn't easy, either:


str(logDAX <- cbind(log(DAX), diff(log(DAX)),
                   diff(diff(log(DAX)))))
colnames(logDAX) <- c('logDAX', 'vel', 'accel')
plot(logDAX, axes=FALSE)
axis(1)
axis(2)


          I'm thinking of creating my own copy of "plot.ts", and changing it so
it accepts the "log" argument as a vector of length equal to ncol of the
ts object to be plotted AND returning an object that would allow a user
to call "axis" ncol times.


          Suggestions?


          Thanks,
          Spencer Graves

HTH,
Eric


On Mon, May 29, 2023 at 7:57?AM Spencer Graves
<spencer.graves at effectivedefense.org> wrote:

Hello, All:


           I want to plot level, velocity, and acceleration in three panels with
only one x axis.  The code below does this using "layout".  However, I
want the three plot areas to be of equal size, and this won't do that:
If I stretch the plot vertically, the relative sizes of the three panels
changes.  There's probably a way to do this with ggplot2, but I have yet
to find it.


           Suggestions?
           Thanks,
           Spencer Graves


str(AirTime <- as.numeric(time(AirPassengers)))
str(AP <- as.numeric(AirPassengers))

def.par <- par(no.readonly = TRUE) # save default, for resetting...
(mat3x1 <- matrix(1:3, 3))
plot3x1 <- layout(mat3x1, heights=c(1.4, 1, 1.5))
layout.show(plot3x1)

par(mar=c(0, 4.1, 4.1, 2.1))
plot(AirTime, AP, log='y', type='l', axes=FALSE,
       main='AirPassengers', ylab='AirPassengers')
box(col='grey')
axis(2, las=1)

par(mar=c(0, 4.1, 0, 2.1))
vAP <- diff(log(AP))
plot(tail(AirTime, -1), vAP, type='l',
       ylab='percent increase', axes=FALSE)
box(col='grey')
axis(2, las=1)

par(mar=c(5.1, 4.1, 0, 2.1))
plot(tail(AirTime, -2), diff(vAP), type='l',
       ylab='acceleration', xlab='year',
       las=1)
box(col='grey')

par(def.par)