Advanced
Vertical Bar Graph, version 3.2
by Sirius Computer Consultants Limited
Retrieving
Graph Data from Files
Both
the applet and servlet can be set to retrieve the graph
data from a data file. The data file is simply a list of
the data names with the value for each data element of the
graph.
The
first 20 character positions of a line in this file specify
the data element name whilst position 21 onwards represent
the value for that data element.
Comment
Lines: Any line in the file which is either blank or
begins with <!-- will be ignored. Therefore comment lines
may be added to file by beginning the line with <!--.
We recommend
that, rather than building a data file from scratch, that
you take a copy of the example file bardata.txt
file and modify the values to suite your implementation.
In both
the applet and servlet, the data file is specified via a
URL parameter and therefore the file can be placed in any
directory (or server) accessible via a URL. However we recommend,for
ease of maintainability, keeping this data file in the same
directory as your web page which incorporates the bar graph.
Data
Element Naming Convention.
The
graph is capable of displaying multiple series of data in
the same chart and therefore it is necessary to specify
which series each piece of data belongs. In addition it
is also important to specify the order in which data should
be taken for each series. This is done by the Name of each
element.
The
data name format is,
dataNseriesM
where
N is an integer number representing this data position within
the series and M is an integer specifying the series. Both
the data and series numbering should be continuous and begin
with 1.
For example if we have 3 series of data each with four pieces
of data the data names would be,
data1series1
data2series1
data3series1
data4series1
data1series2
data2series2
data3series2
data4series2
data1series3
data2series3
data3series3
data4series3
Data
Values
The
data value for each piece of data can either be an integer
or real / floating point number. In addition if the data
file is being constructed for use by the applet, two further
elements may be added, which define a URL and a Target frame
for this data's bar. To add a URL and target frame to a
piece of data simply add the URL and target frame name to
the end of the line separating each with comma ","
character.
e.g..
data1series1 7000,http://www.jpowered.com,framename
In the
applet implementation the URL and Target elements may also
be used to execute a piece of JavaScript within the HTML
page. For further details on this please see the section
"Bar Graph & JavaScript"
Please
Note: URL and Frame specification is not valid for the
servlet implementation.
[