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    <p>This seems to work - sort of. It would probably be a good start anyway.</p> <pre><code>public class CSVFun { // Where to start the scan of the function. static final double Start = 0.0; // End of scan. static final double End = 10000.0; // Fine enough to detect a change in the function. static final double BigStep = 0.1; // Finest resolution. static final double SmallStep = 0.000000001; // Work out some csv for a function. private static void csv(F f) { System.out.println("Function: " + f); // Start at 0. double t = Start; double ft = f.f(t); System.out.println(t + "," + ft); while (t &lt; End) { // Walk to the end. double step = BigStep; // Find a break point. while (t &lt; End &amp;&amp; f.f(t) == ft) { t += step; } if (t &lt; End) { // Back one. t -= step; // Zoom in on the transition point. while (step &gt; SmallStep) { // Go smaller. step /= 10; // Walk forward. while (t &lt; End &amp;&amp; f.f(t) == ft) { t += step; } // Back one. t -= step; } // Before System.out.println(t + "," + ft); // One more forward. t += step; } // Print. if (f.f(t) != ft) { ft = f.f(t); System.out.println(t + "," + ft); } } } // Tests the process with the sample functions below. public static void main(String[] args) { try { for (F f : F.values()) { csv(f); } } catch (Exception ex) { ex.printStackTrace(); } } // The sample functions - Encoded in Java enum F { A { @Override double f(double t) { if (t &lt; 60) { return (0.1); } if (t &gt; 66.0115) { return (0.1); } return 1; } }, B { @Override double f(double t) { if (t &gt; 0.5) { return 2; } return 3; } }, C { @Override double f(double t) { if (t &gt;= 0.5) { return 2; } return 3; } }, D { @Override double f(double t) { if (t &lt; 0.5) { return 2; } return 3; } }, E { @Override double f(double t) { if (t &lt;= 0.5) { return 2; } return 3; } }, F { @Override double f(double t) { if ((t &gt;= 3600) &amp; (t &lt;= 3660)) { return 25; } return 0; } },; abstract double f(double t); } } </code></pre> <p>Output:</p> <pre><code>Function: A 0.0,0.1 59.999999999000565,0.1 60.00000000000056,1.0 66.01149999900045,1.0 66.01150000000045,0.1 Function: B 0.0,3.0 0.49999999999999994,3.0 0.500000001,2.0 Function: C 0.0,3.0 0.49999999999999983,3.0 0.5000000009999999,2.0 Function: D 0.0,2.0 0.49999999999999983,2.0 0.5000000009999999,3.0 Function: E 0.0,2.0 0.49999999999999994,2.0 0.500000001,3.0 Function: F 0.0,0.0 3599.9999999998213,0.0 3600.0000000008213,25.0 3659.999999999771,25.0 3660.000000000771,0.0 </code></pre> <p>Which is close I think.</p>
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    1. POConvert a piecewise function to a CSV file using Java
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    1. COThis is definitely a start, however my main problem is creating a more general converter so that I don't have to write a special case for each possible piecewise expression.
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    2. COI have encoded your examples (as A, B, C, D, E and F) and used a general algorithm to generate a csv for each. I think all that is left is some rounding rules and you're done, unless I have misunderstood your question.
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    3. COAh, I had misunderstood what you were doing.
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