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The evaluation of expression in the C, C++, and Java programming languages is one of the most difficult topics. Students have problems with both understanding the order of execution and the semantics of operators. To help the students we have developed cWADEIn and jWADEIn. Both systems allow students to explore the process of expression evaluation step-by-step with detailed visualizations and explanations. They also help them to check their understanding of the order of execution and semantics of operators. From research point of view, the goal of the systems is to explore adaptive explanatory visualizations. Either of the systems can work in two modes: exploration and knowledge evaluation.

In the exploration mode the system presents complex visualizations. Color-coding is used to facilitate understanding. Animations are used in many contexts. As the student progresses the speed of those animations increases. Eventually, animations are collapsed. Each visualization step is accompanied by textual explanations. Those explanations are context-sensitive and attempt to shed light on the step at hand as opposed to giving more general information. As the student progresses explanations are being collapsed as well. Eventually, no explanations are shown. In the knowledge evaluation mode the systems checks the student's knowledge of execution order and semantics of operators.


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System development is currently supported by NSF(Directorate for Education and Human Resources) through Award #0426021

Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.


WADEIn Exploration Mode
cWADEIn Explore Mode
WADEIn Evaluation Mode
cWADEIn Evaluation Mode

Try cWADEIn and jWADEIn

Recent Publications

Brusilovsky, P. and Loboda, T. (2006). WADEIn II: A Case for Adaptive Explanatory Visualization. Proceedings of 11th Annual Conference on Innovation and Technology in Computer Science Education, ITiCSE'2006, Bologna, Italy, June 26-28, 2005, ACM Press, pp. 48-52. [PDF]

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Tomek Loboda, Peter Brusilovsky

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