Plot3d: Plot3d generates a 3-dimensional plot using the package...

In gmonette/p3d: Plot 3d Data and Fitted Surfaces

Plot3d generates a 3-dimensional plot using the package rgl.

Description

Plot3d generates a 3-dimensional plot of points using the package rgl. A grid of points for the x and z variables and an optional factor variable is kept as an object in order to allowing plotting fitted surfaces that are functions of the x and z variables and the optional factor.

Usage

## S3 method for class 'formula'

Plot3d(formula = attr(data, "formula"),
    data = sys.parent(),
    groups = NULL,
    subset = NULL,
    xlab = names(dd)[2],
    ylab = names(dd)[1],
    zlab = names(dd)[3],
    verbose = 0,
    col = c("blue", "green", "orange", "magenta", "cyan", "red", "yellow", "gray"),
    surface = FALSE,
    fit = "smooth",
    surface.col = col,
    lines.col = "gray",
    lines.lwd = 1,
    theta = 0,
    phi = 15,
    fov = 15,
    zoom = 1,
    keep.view = FALSE,
    ...)

## S3 method for class 'lm'

  Plot3d(fit, ...)

## S3 default method

  Plot3d(x, y, z, xlab, ylab, zlab, groups = NULL, ...)

Arguments

formula	a two sided formula of the form y ~ x + z | [g] where y is the variable plotted on the vertical axis, x is plotted on the horizontal axis and z is plotted along the axis coming out of the screen. g is interpreted as a factor and the index of its levels is used to select the value of col used.
data	a data frame in which formula is evaluated.
groups	a variable used to join points belonging to the same group by lines
subset	is a condition to select a subset of data.
xlab, ylab, zlab	labels for respective axes
verbose
col
surface	if TRUE, a non-parametric regression surface(s) are drawn.
fit
surface.col
lines.col
lines.lwd
theta, phi, fov, zoom	are arguments passed to view3d for the initial view. theta is the amount of rotation of the object aroud a vertical axis in degrees clockwise as seen from above, phi is the elevation of the eye in degrees above a horizontal plane. By default, rotation maintains the verticality of the vertical axis to respect the way in which regression is normally visualized. fov = 0 produces an orthogonal projection with no perspective distortion. However, the impression of seeing data in 3D may be difficult to evoke. Thus a frontal orthographic projection is achieved with phi = 0, fov = 0, theta = 0.
keep.view	if TRUE, the previous point of view is maintained.
...

Examples

## Not run: 
    library(p3d)
    data(Smoking)
    head(Smoking)
    rownames(Smoking) = Smoking$Country

    Init3d(family = 'serif', cex = 1.5)
    Plot3d( LE ~ CigCon + HealthExpPC | Continent, Smoking)
    Axes3d()
    Identify3d(pad=1)


    fit = lm( LE ~ CigCon + log(HealthExpPC) +I(CigCon^2) + I(log(HealthExpPC)^2) + I(CigCon*log(HealthExpPC)), Smoking)
    Fit3d( fit )
    fitl <- lm( LE ~ CigCon + HealthExpPC, Smoking)
    Fit3d( fitl, col = 'pink')
# HEpCap is highly 'skewed': dense on left, long tail on right
    require( lattice )
    densityplot( Smoking$HealthExpPC )

# Useful to use a transformation to make spread more even
#  e.g. log
# First make sure all values are positive:

    sort( Smoking$HealthExpPC)

# Do log transformation:

    Smoking$LogHE <- log(Smoking$HealthExpPC)    # create log HE

    densityplot( Smoking$LogHE )

# Also usefult to have categories:

    Smoking$HECat <- cut(Smoking$LogHE, 7)       # create categories
    summary(Smoking)

    Plot3d( LE ~ CigCon + LogHE |HECat, Smoking )  # condition on level of HEpC
    Axes3d()
    Ell3d()
    Identify3d(pad=1)

# Simple regression

    fit.lin <- lm( LE ~ CigCon, Smoking)
    Fit3d( fit.lin )
    fit.lin2 <- lm(LE ~ CigCon, subset(Smoking, Continent != "Africa"))
    Fit3d( fit.lin2)
    Pop3d(4)

# Use multiple regression (advanced version with quadratic surface)

    fit = lm( LE ~ CigCon + I(LogHE^2) +I(CigCon^2) + I(LogHE^2) + I(CigCon*LogHE), Smoking)
    Fit3d( fit, col = 'red' )
    Pop3d(2)

# refit omitting Africa:

    fit.na = lm( LE ~ CigCon + I(LogHE^2) +I(CigCon^2) + I(LogHE^2)
               + I(CigCon*LogHE), Smoking, subset = Continent != "Africa")
    Fit3d( fit.na, col = 'red' )

# Marginal relationship

    Pop3d(4)    # pop twice for each fit
    fit.quad <- lm( LE ~ CigCon + I(CigCon^2) , Smoking)
    Fit3d( fit.quad, col = 'green')

#  A quadratic surface within each Continent (overfitting?!)

    fit2 = lm( LE ~ Continent*(CigCon + HealthExpPC +I(CigCon^2) +
            I(HealthExpPC^2) + I(CigCon*HealthExpPC)), Smoking)
    Fit3d( fit2 )

#  For a 2D view of the y versus x

    view3d(0,0,0)   # note the first parameter, theta, rotates clockwise in the vertical axis
                    # from the initial position given by view3d(0,0,0); the second
                    # parameter, phi, tilts the graph around a horizontal screen axis
                    # towards the viewer.  The third parameter, fov, affects the
                    # amount of 'perspective'. fov = 0 yields an orthographic
                    # projection

## End(Not run)

gmonette/p3d documentation built on Nov. 16, 2023, 11:31 p.m.