students

How to download and try this example

Usage: pl -gif students.htm

This example can take a variable number of data fields.
It uses a loop to iterate across fields 3 .. N (fields 1 and 2 are identifiers).
The first record of data contains field names.
These names are accessed using the $fieldname() function and added to
the legend.



#set COLORLIST = red,yellow,blue,green,orange,pink,black,white

// added scg 8/4/04.. allows spaces to be represented using underscores..
#proc settings
  encodenames: yes

#proc page
pagesize: 7 4
#if @DEVICE in gif,png
  scale: 0.6
#endif

#proc getdata
fieldnameheader: yes
#intrailer	// get data from end of this file
#endproc   //necessary in order to do the following computation involving NRECORDS

// compute XMAX (number of records+1 for bar graphs)
#set XMAX = $arith(@NRECORDS+1)  

// set up area
#proc areadef
title: Student exam scores
rectangle: 1 1 6 3
xrange: 0 @XMAX
yrange: 0 100   // no way currently to do autorange on variable # of fields
xaxis.stubs: datafield=1
xaxis.label: Student
yaxis.stubs: inc 10
yaxis.label: Score

// initialize loop variables
#set I = 3
#set NCLUST = $arith(@NFIELDS-2)

// start loop
#loop

  // set vars for this iteration
  #set FNAME = $fieldname(@I)   // this function is new
  #set ICLUST = $arith(@I-2)
  #set COLOR = $nmember(@ICLUST,@COLORLIST)

  // do bars
  #proc bars
  lenfield: @I
  cluster: @ICLUST / @NCLUST
  color: @COLOR
#hideund
  legendlabel: @FNAME
#showund
  barwidth: 0.1

  // update I and see if time to stop..
  #set I = $arith(@I+1)
  #if @I > @NFIELDS
    #break
  #endif
#endloop

// slap on the legend
#proc legend
format: singleline
location: 1 0.5
sep: 0.5

// here's the data
#proc trailer
data:
id group Exam_a Exam_b Exam_c Exam_d
01001 N 44 45 71 89
01002 N 56 44 54 36
01003 B 46 63 28 87
01004 B 42 28 39 49
01005 B 52 74 84 66