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DESCRIPTIONPlotting is driven by data. The plot data may be specified within a ploticus script, or it may be contained in a file, or be the result of executing a shell command. proc getdata is used to specify or read in plotting data.Ploticus uses field-oriented data. Most plotting is done based on fields. For example, a bargraph can be rendered based upon the values in field #2 of each row of data. A set of data should contain one or more rows (lines). Fields may be delimited in one of three ways. The delimitation must be specified in proc getdata. The three ways are:
Fields may be surrounded by "double quotes"; this must be done when a field contains embedded delimiter characters. The number of fields should be consistent across records. A comment character (specified as a proc getdata attribute) may be given as the first character on a line; it causes that line to be ignored. Beginning in version 1.40 it is possible to set ploticus variables from within a data file using the construct: #set VARIABLE = value. EXAMPLESGallery examples include:scat7.dat (white-space delimited) stock.csv (comma delimited) timeline3 (data specified within script) km2 (data specified within script). DETAILSThe plotting procedures generally access specific fields and process the data from top to bottom. For example, a bar graph might be made by drawing one bar for each data record based on the value in field 2.
Proc getdata
is used to read in a data file for plotting.
After proc getdata has been executed,
the plotting procedures can access the data by
record and field.
HANDLING MISSING DATAPloticus can handle missing plot data values. In data sets that are to be plotted, missing items should be denoted by a value that is not plottable, e.g. for numeric data, a value that is non-numeric. The plotting procedures omit non-plottable values (the details of how this is handled are given in the man page for each plotting proc). An Gallery example involving missing numeric data represented by dashes(-) is volunteers |
![]() data display engine Copyright Steve Grubb ![]() |