Stochastic Local Search Based CSP Solver use stochastic local search algorithms to solve constraint satisfaction problems. Constraint satisfaction problems (CSPs) are pervasive in AI problems. A constraint satisfaction problem is the problem of assigning values to variables that satisfy some constraints. This CSP solver uses stochastic local search algorithms to attempt to find assignments to the variables which satisfy the constraints using heuristics in a local neighbourhood.

A constraint satisfaction problem, or CSP, is a problem which can be expressed as a set of variables, each with a particular domain, and a set of constraint relations between variables. A solution to a CSP is an assignment of a unique value to each variable such that all the of the constraint relations are satisfied.
This applet is designed to let you create such a problem and solve it using and experimenting with a variety of stochastic local search algorithms.

Creating Problems:
Building a problem yourself should be straightforward - just make sure that you're in "Create Mode". To create variables, click on the "Create Variable" button, then click on the white canvas to bring up a dialog box where you can specify all the variable information. Creating Constraints is just as easy. Check the extended help if you're having problems, or if you don't understand what all the terminology means.

Solving Problems:
Once you have acquired a CSP you want to solve, click the "Solve" tab above the main canvas to start solving.

First initialize the search by clicking on the "Initialize" button.

Then there are three ways to solve the CSPs:
1. Select a variable by clicking on it, and change it's current value.
2. Step through the search using the "Step" or "Fine Step" button, letting the program automatically pick a neighbour at each step.
3. Let the program do all the work by clicking "Auto Solve".
4. You can adjust the speed of Auto Solve by selecting the desired checkbox under 'Auto Solve Speed' under the 'Hill Options' menu.

At any point during the search you can return to a previous assignment using the "Trace" window by pressing the "Step Back" button or by selecting a previous assignment in the Trace display and then pressing "Set CSP". You may also watch the progress of the search by pressing the show plot button.

Requirements:
* Java

The license of this software is Freeware, you can free download and free use this calculator software.