multi.hist function

Multiple histograms with density and normal fits on one page

Multiple histograms with density and normal fits on one page

Given a matrix or data.frame, produce histograms for each variable in a "matrix" form. Include normal fits and density distributions for each plot.

The number of rows and columns may be specified, or calculated. May be used for single variables.

multi.hist(x,nrow=NULL,ncol=NULL,density=TRUE,freq=FALSE,bcol="white",
      dcol=c("black","black"),dlty=c("dashed","dotted"),
      main=NULL,mar=c(2,1,1,1),breaks=21,global=TRUE,...)
histBy(x,var,group,data=NULL,density=TRUE,alpha=.5,breaks=21,col,xlab,
            main="Histograms by group",freq=FALSE,...)

Arguments

  • x: matrix or data.frame
  • var: The variable in x to plot in histBy
  • group: The name of the variable in x to use as the grouping variable
  • data: Needs to be specified if using formula input to histBy
  • nrow: number of rows in the plot
  • ncol: number of columns in the plot
  • density: density=TRUE, show the normal fits and density distributions
  • freq: freq=FALSE shows probability densities and density distribution, freq=TRUE shows frequencies
  • bcol: Color for the bars
  • dcol: The color(s) for the normal and the density fits. Defaults to black.
  • dlty: The line type (lty) of the normal and density fits. (specify the optional graphic parameter lwd to change the line size)
  • main: title for each panel will be set to the column name unless specified
  • mar: Specify the lower, left, upper and right hand side margin in lines -- set to be tighter than normal default of c(5,4,4,2) + .1
  • xlab: Label for the x variable
  • breaks: The number of breaks in histBy (see hist)
  • global: If TRUE, use the same x-axis for all plots
  • alpha: The degree of transparency of the overlapping bars in histBy
  • col: A vector of colors in histBy (defaults to the rainbow)
  • ...: additional graphic parameters (e.g., col)

Details

This allows for quick summaries of multiple distributions. Particularly useful when examining the results of multiple-split halves that come from the reliability function.

By default, will try to make a square plot with equal number of rows and columns. However, the number of columns and rows may be specified for a particular plot.

Author(s)

William Revelle

See Also

bi.bars for drawing pairwise histograms and scatterHist for bivariate scatter and histograms. densityBy, violinBy and violin for density plots.

Examples

multi.hist(sat.act) 
multi.hist(sat.act,bcol="red")
multi.hist(sat.act,dcol="blue")  #make both lines blue
multi.hist(sat.act,dcol= c("blue","red"),dlty=c("dotted", "solid")) 
multi.hist(sat.act,freq=TRUE)   #show the frequency plot
multi.hist(sat.act,nrow=2)
histBy(sat.act,"SATQ","gender") #input by variable names
histBy(SATQ~ gender, data=sat.act) #formula input
psych packageRead PDF manual