A. The Plotter Output Syntax
When used in plotter mode, the plugins write information about each plot which is generated to standard output. This output is designed to be parsed by some kind of wrapper which presents the plots in a more user friendly way.
A.1. Formal Syntax Definition
output = 1*(imagedata) imagedata = title start end-p image width height 1*(plotdata) end plotdata = dimension unit avg min max last title = "TITLE" ws string lf start = "START" ws integer lf end-p = "END" ws integer lf image = "IMAGE" ws string lf width = "WIDTH" ws integer lf height = "HEIGHT" ws integer lf dimension = "DIMENSION" ws string lf unit = "UNIT" ws string lf avg = "AVG" ws float lf min = "MIN" ws float lf max = "MAX" ws float lf last = "LAST" ws float lf end = "END" lf string = chars-nb *chars-b ; a string is a concatenation of one non blank character ; and any number of characters including blanks. chars-nb = (%x21-FF) ; a non blank character is any character with an ASCII ; value greater 32 decimal. chars-b = (%x20-FF) ; a character including blank is any character with an ; ASCII value greater or equal 32 decimal. integer = ["-"] 1*(%x30-39) ; an integer is a optional minus followed by at least one ; decimal digit. float = ["-"] 1*(%x30-39) "." 1*(%x30-39) ; a float is a optional minus followed by at least one ; decimal digit followed by a dot followed by at least one ; decimal digit. ws = 1*(%d32) ; whitespace is one or more blank character (ASCII 32). lf = %d10 ; line feed is one linefeed character (ASCII 10).
Notes about the syntax definition:
A.2. Convenient Description
While ABNF may be the perfect tool to define the syntax of the plotter output, describing it is a lot simplier.
The output consists of several blocks each describing one image. Each block consists of lines where each line in turn consists of a keyword and a value separated by one or more blanks. There is one exception to the keyword-value pair rule, which is the “END” line without value, which ends one image block.2
Within each image block there are several “plot” blocks, each containing information about one plot i. e. one curve.
The semantics of the lines—in order of apperance—are:
2Two different cases where “END” is used may be considered a design error.
3Seconds since 1970-01-01 00:00:00 UTC
|Copyright © 2006, 2007 Peter Gritsch|