New SymbolicExpressionLengthTreeAnalyzer

[bburlacu]

This new analyzer can be used to visualize the distribution of tree lengths within the running population, in the form of a histogram (it will show the frequency, i.e. number of individuals in the population, of each possible tree length).

The histogram consists of a number of bins equal to the number of possible tree lengths, ranging from the minimum to the maximum allowed tree length (so the interval width will always be 1), and depending on this number, it can automatically adjust the scale which is displayed on the X-axis.

Additionally, the analyzer has an option to record the history of the tree length distributions from each generation.

[bburlacu]

r6978: Added SymbolicExpressionTreeLengthAnalyzer. Added new scalingFactory visual property for table data rows (for dynamically adjusting the histogram scale depending on the number of bins) + scaling logic inside the tree length analyzer, adjusted DataTableView.

[mkommend]

Reviewing comments:

• The naming of the results generated by the analyzer must be improved
• Addressing results or parameters in code should be done by constants instead of literals

[bburlacu]

r7124: Improved naming of variables and replaced literals with constants. Added new IsVisibleInLegend visual property for data rows.

[bburlacu]

r7126: Modified the DataTableView to take the IsVisibleInLegend property into account for all chart types. Added default value for the IsVisibleInLegend property in the storable constructor (the property is true by default, identical to the old behavior).

[mkommend]

The analyzer currently does not work with the OSGA.

[bburlacu]

r7143: Refactored some bits in the SymbolicExpressionTreeLengthAnalyzer. It now works with GA and it mostly works with OSGA, short of an interesting bug that I couldn't yet track down.

The bug occurs in the following situation:

• Using OSGA with the SymbolicExpressionTreeLengthAnalyzer turned on
• Everything works until the user wants to see the graphical histogram
• During the update of the bar chart/histogram, at some point the chart throws an overflow exception (possible a divide by zero or related). The exception is followed by a long stack trace involving WinForms? and the Graphics system.

The user can click continue and run again (if the histogram is not displayed then everything is fine)

[bburlacu]

r7147: Fixed a couple of bugs in the SymbolicExpressionTreeLengthAnalyzer and made some minor aesthetic changes (relating to the way chart columns are displayed).

[mkommend]

Reviewing comments:

• Improve the y-axis scaling
• Hide rarely changed and lookup parameters
• Name the DataTables correctly
• Remove the unnecessary generations counter

[bburlacu]

r7150: Simplified the Y-axis scaling, removed generations counter, hid some parameters and renamed the history data table.

[bburlacu]

r7223: Fixed bug in the CalculateHistogram method inside the DataTableView, adjusted the way vertical scaling is performed in the SymbolicExpressionTreeLengthAnalyzer.

[mkommend]

r7227: Corrected AfterDeserialization in SymbolicExpressionTreeLengthAnalyzer.

[mkommend]

Can you please have a look at the changes regarding the DataTable histogram.

[abeham]

Works very well, thanks!

[ascheibe]

r7230 fixed compiler warnings and removed duplicated interface

[mkommend]

Thx for changing this minor code issues.

[bburlacu]

r861: Fixed bug in storable constructor call in the SymbolicExpressionTreeLengthAnalyzer.