<stránka

	xmlns="https://trac.frantovo.cz/xml-web-generator/wiki/xmlns/strana"

	xmlns:m="https://trac.frantovo.cz/xml-web-generator/wiki/xmlns/makro">

	<nadpis>Generating statistics and charts using XMLTable</nadpis>

	<perex>read a XML file and get a visual overview</perex>

	<m:pořadí-příkladu>03100</m:pořadí-příkladu>

	<text xmlns="http://www.w3.org/1999/xhtml">

		<p>

			We are currently finalizing guidelines called <a href="https://sane-software.globalcode.info/">Sane software manifesto</a> 

			(<a href="https://hg.globalcode.info/sane-software/sane-software-manifesto/">sources</a>).

			This document consists of chapters and items. An item might be a requirement, a recommendation or an information.

			In order to get a high-level overview, we generate statistics showing the counts of items of forementioned types in particular chapters.

			Whole document is built using GNU Make, so we call also <m:name/> commands from the Makefile:

		</p>

		<m:pre jazyk="makefile" src="examples/ssm-xmltable-1.makefile"/>

		<p>

			The first Makefile target stores relational data in the file <code>statistics.rp</code> (which is re/generated only if <code>ssm.en.xml</code> has been changed).

			And then this file is used twice: for terminal output using <code>relpipe-out-tabular</code> and for visual output with a chart using <code>relpipe-out-gui</code>.

		</p>

		<p>

			The <code>relpipe-in-xmltable</code> simply counts items (requirements, recommendations, informations, totals) in each chapter using XPath expressions.

			So we can see how <em>heavy</em> and strict particular chapters are:

		</p>

		<m:pre jazyk="text" src="examples/ssm-xmltable-1.txt"/>

		<p>

			However – for such data – much better than a table is a chart.

			So we pipe the raw relational data prepared in the <code>build/statistics.rp</code> to the <code>relpipe-out-gui</code> command.

			But because this tool counts totals itself and stacks the values in the bar chart,

			we remove the <code>items_total</code> attribute from the relation using <code>relpipe-tr-cut</code> transformation.

			Thanks to regular expressions, it is very concise. But of course, we can make it more explicit:

		</p>

		<m:pre jazyk="bash"><![CDATA[relpipe-tr-cut --relation "chapter" --attribute "(name|requirements|recommendations|informations)"

#            relation name ^                     ^ attribute names to be passed through (others are filtered out)]]></m:pre>

		<p>We also set the window title (using the <code>-title</code> Qt option) and get the chart:</p>

		<m:img src="img/sane-software-statistics-chart-1.png"/>

		<p>

			Using these tools we can get statistics and charts from any XML or other supported format like CSV, Recfile or a <a href="https://sql-dk.globalcode.info/">database</a>.

			We can also do advanced computations using SQL, Guile or AWK before piping the data to the GUI.

		</p>

	</text>

</stránka>