Learn R Programming

relax (version 1.3.15)

slider: slider / button control widgets

Description

slider and gslider construct a Tcl/Tk-widget with sliders and buttons to demonstrate the effects of variation of parameters on calculations and plots.

Usage

slider(sl.functions, sl.names, sl.mins, sl.maxs, sl.deltas, sl.defaults, but.functions, but.names, no, set.no.value, obj.name, obj.value, reset.function, title, prompt=FALSE, sliders.frame.vertical=TRUE)
gslider(sl.functions, sl.names, sl.mins, sl.maxs, sl.deltas, sl.defaults, but.functions, but.names, no, set.no.value, obj.name, obj.value, reset.function, title, prompt=FALSE, sliders.frame.vertical=TRUE, hscale=1, vscale=1, pos.of.panel = c("bottom","top","left","right")[1])

Arguments

sl.functions
set of functions or function connected to the slider(s)
sl.names
labels of the sliders
sl.mins
minimum values of the sliders' ranges
sl.maxs
maximum values of the sliders' ranges
sl.deltas
change of step per click
sl.defaults
default values for the sliders
but.functions
function or list of functions that are assigned to the button(s)
but.names
labels of the buttons
no
slider(no=i) requests slider i
set.no.value
slider(set.no.value=c(i,val)) sets slider i to value val
obj.name
slider(obj.name=name) requests the value of variable name from environment slider.env
obj.value
slider(obj.name=name,obj.value=value) assigns value to variable name in environment slider.env
reset.function
function that induce a reset.button and contains the commands of it.
title
title of the control window
prompt
if TRUE slider functions are called by moving a slider, if FALSE slider functions are called after releasing the mouse button
sliders.frame.vertical
if TRUE the sliders are stacked one above the other; otherwise they are positioned side by side
hscale
horizontal scale factor for image size; compare tkrplot in package tkrplot
vscale
vertical scale factor for image size; compare tkrplot in package tkrplot
pos.of.panel
position of the panel field for sliders and buttons. Value of pos.of.panel: bottom, top, left or right.

Value

Using slider in definition mode slider returns the value of new created the top level widget. slider(no=i) returns the actual value of slider i. slider(obj.name=name) returns the value of variable name in environment slider.env. gslider return in definition mode the result of tkrplot which was called to construct the widget.

Details

slider constructs a separated panel for controlling the parameters whereas gslider integrates a graphical device and buttons and sliders within one window.

The following actions can be done: a) definition of (multiple) sliders and buttons, b) request or specification of slider values, and c) request or specification of variables in the environment slider.env. The management takes place in the environment slider.env. If slider.env is not found it is generated.

Definition ... of sliders: First of all you have to define sliders, buttons and the attributes of them. Sliders are established by six arguments: sl.functions, sl.names, sl.minima, sl.maxima,sl.deltas, and sl.defaults. The first argument, sl.functions, is either a list of functions or a single function that contains the commands for the sliders. If there are three sliders and slider 2 is moved with the mouse the function stored in sl.functions[[2]] (or in case of one function for all sliders the function sl.functions) is called.

DEFINITION ... of buttons: Buttons are defined by a vector of labels but.names and a list of functions: but.functions. If button i is pressed the function stored in but.functions[[i]] is called.

REQUESTING ... a slider: slider(no=1) returns the actual value of slider 1, slider(no=2) returns the value of slider 2, etc. You are allowed to include expressions of the type slider(no=i) in functions describing the effect of sliders or buttons.

SETTING ... a slider: slider(set.no.value=c(2,333)) sets slider 2 to value 333. slider(set.no.value=c(i,value)) can be included in the functions defining the effects of moving sliders or pushing buttons.

VARIABLES ... of the environment slider.env: Sometimes information has to be trransferred back and forth between functions defining the effects of sliders and buttons. Imagine for example two sliders: one to control p and another one to control q, but they should satisfy: p+q=1. Consequently, you have to correct the value of the first slider after the second one was moved. To prevent the creation of global variables store them in the environment slider.env. Use slider(obj.name="p.save",obj.value=1-slider(no=2)) to assign value 1-slider(no=2) to the variable p.save . slider(obj.name=p.save) returns the value of variable p.save.

Dependencies The function gslider depends on package tkrplot.

Examples

Run this code

# example 1, sliders only
## Not run: 
# ## This example cannot be run by examples() but should work in an interactive R session
# plot.sample.norm<-function(){
#  refresh.code<-function(...){
#    mu<-slider(no=1); sd<-slider(no=2); n<-slider(no=3)
#    x<-rnorm(n,mu,sd)
#    plot(x)
#  }
#  slider(refresh.code,sl.names=c("value of mu","value of sd","n number of observations"),
#        sl.mins=c(-10,.01,5),sl.maxs=c(+10,50,100),sl.deltas=c(.01,.01,1),sl.defaults=c(0,1,20))
# }
# plot.sample.norm()
# ## End(Not run)

# example 2, sliders and buttons
## Not run: 
# ## This example cannot be run by examples() but should work in an interactive R session
# plot.sample.norm.2<-function(){
#  refresh.code<-function(...){
#    mu<-slider(no=1); sd<-slider(no=2); n<-slider(no=3)
#    type=  slider(obj.name="type")
#    x<-rnorm(n,mu,sd)
#    plot(seq(x),x,ylim=c(-20,20),type=type)
#  }
#  slider(obj.name="type",obj.value="l")
#  slider(refresh.code,sl.names=c("value of mu","value of sd","n number of observations"),
#        sl.mins=c(-10,.01,5),sl.maxs=c(10,10,100),sl.deltas=c(.01,.01,1),sl.defaults=c(0,1,20),
#        but.functions=list(
#               function(...){slider(obj.name="type",obj.value="l");refresh.code()},
#               function(...){slider(obj.name="type",obj.value="p");refresh.code()},
#               function(...){slider(obj.name="type",obj.value="b");refresh.code()}
#        ),
#        but.names=c("lines","points","both"))
# }
# plot.sample.norm.2()
# ## End(Not run)

# example 2a, sliders and buttons and graphics in one window
## Not run: 
# ## This example cannot be run by examples() but should work in an interactive R session
# plot.sample.norm.2<-function(){
#  refresh.code<-function(...){
#    mu<-slider(no=1); sd<-slider(no=2); n<-slider(no=3)
#    type=  slider(obj.name="type")
#    x<-rnorm(n,mu,sd)
#    plot(seq(x),x,ylim=c(-20,20),type=type)
#  }
#  slider(obj.name="type",obj.value="l")
#  gslider(refresh.code,sl.names=c("value of mu","value of sd","n number of observations"),
#        sl.mins=c(-10,.01,5),sl.maxs=c(10,10,100),sl.deltas=c(.01,.01,1),sl.defaults=c(0,1,20),
#        but.functions=list(
#               function(...){slider(obj.name="type",obj.value="l");refresh.code()},
#               function(...){slider(obj.name="type",obj.value="p");refresh.code()},
#               function(...){slider(obj.name="type",obj.value="b");refresh.code()}
#        ),
#        but.names=c("lines","points","both"))
# }
# plot.sample.norm.2()
# ## End(Not run)

# example 3, dependent sliders
## Not run: 
# ## This example cannot be run by examples() but should work in an interactive R session
# print.of.p.and.q<-function(){
#  refresh.code<-function(...){
#    p.old<-slider(obj.name="p.old")
#    p<-slider(no=1); if(abs(p-p.old)>0.001) {slider(set.no.value=c(2,1-p))}
#    q<-slider(no=2); if(abs(q-(1-p))>0.001) {slider(set.no.value=c(1,1-q))}
#    slider(obj.name="p.old",obj.value=p)
#    cat("p=",p,"q=",1-p,"\n")
#  }
#  slider(refresh.code,sl.names=c("value of p","value of q"),
#        sl.mins=c(0,0),sl.maxs=c(1,1),sl.deltas=c(.01,.01),sl.defaults=c(.2,.8))
#  slider(obj.name="p.old",obj.value=slider(no=1))
# }
# print.of.p.and.q()
# ## End(Not run)

# example 4, rotating a surface
## Not run: 
# ## This example cannot be run by examples() but should work in an interactive R session
# R.veil.in.the.wind<-function(){
#   # Mark Hempelmann / Peter Wolf
#   par(bg="blue4", col="white", col.main="white", 
#       col.sub="white", font.sub=2, fg="white") # set colors and fonts
#   refresh.code<-function(...){
#     samp        <- function(N,D) N*(1/4+D)/(1/4+D*N) 
#     z<-outer(seq(1, 800, by=10), seq(.0025, 0.2, .0025)^2/1.96^2, samp) # create 3d matrix
#     h<-100 
#     z[10:70,20:25]<-z[10:70,20:25]+h; z[65:70,26:45]<-z[65:70,26:45]+h
#     z[64:45,43:48]<-z[64:45,43:48]+h; z[44:39,26:45]<-z[44:39,26:45]+h
#     x<-26:59; y<-11:38; zz<-outer(x,y,"+"); zz<-zz*(65<zz)*(zz<73)
#     cz<-10+col(zz)[zz>0];rz<-25+row(zz)[zz>0]; z[cbind(cz,rz)]<-z[cbind(cz,rz)]+h
#     theta<-slider(no=1); phi<-slider(no=2)
#     persp(x=seq(1,800,by=10),y=seq(.0025,0.2,.0025),z=z,theta=theta,phi=phi, 
#           scale=T, shade=.9, box=F, ltheta = 45,
#           lphi = 45, col="aquamarine", border="NA",ticktype="detailed")   
#   }
#   slider(refresh.code, c("theta", "phi"), c(0, 0),c(360, 360),c(.2, .2),c(85, 270)  )
# }
# R.veil.in.the.wind()
# ## End(Not run)

Run the code above in your browser using DataLab