Making a 3D surface from time series data in R

问题

I have a large data set which I would like to make a 3D surface from. I would like the x-axis to be the date, the y-axis to be the time (24h) and the z-axis (height) to be a value I have ($). I am a beginner with R, so the simpler the better!

http://www.quantmod.com/examples/chartSeries3d/ has a nice example, but the code is way to complicated for my skill level!

Any help would be much appreciated - anything I have researched so far needs to have the data sorted, which is not suitable I think.

回答1:

Several options present themselves, persp() and wireframe(), the latter in package lattice.

First some dummy data:

set.seed(3)
dat <- data.frame(Dates = rep(seq(Sys.Date(), Sys.Date() + 9, by = 1), 
                              each = 24),
                  Times = rep(0:23, times = 10),
                  Value = rep(c(0:12,11:1), times = 10) + rnorm(240))

persp() needs the data as the x and y grid locations and a matrix z of observations.

new.dates <- with(dat, sort(unique(Dates)))
new.times <- with(dat, sort(unique(Times)))
new.values <- with(dat, matrix(Value, nrow = 10, ncol = 24, byrow = TRUE))

and can be plotted using:

persp(new.dates, new.times, new.values, ticktype = "detailed", r = 10, 
      theta = 35, scale = FALSE)

The facets can be coloured using the col argument. You could do a lot worse than study the code for chartSeries3d0() at the page you linked to. Most of the code is just drawing proper axes as neither persp() nor wireframe() handle Date objects easily.

As for wireframe(), we

require(lattice)
wireframe(Value ~ as.numeric(Dates) + Times, data = dat, drape = TRUE)

You'll need to do a bit or work to sort out the axis labelling as wireframe() doesn't work with objects of class "Date" at the moment (hence the cast as numeric).

来源：https://stackoverflow.com/questions/6432996/making-a-3d-surface-from-time-series-data-in-r

标签

geometry-surface