X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=core%2Fsrc%2Fnet%2Fsf%2Fopenrocket%2Fsimulation%2Fcustomexpression%2FIndexExpression.java;fp=core%2Fsrc%2Fnet%2Fsf%2Fopenrocket%2Fsimulation%2Fcustomexpression%2FIndexExpression.java;h=6fb084de4154f18ab2b66436acf8334c497bf137;hb=9349577cdfdff682b2aabd6daa24fdc3a7449b58;hp=0000000000000000000000000000000000000000;hpb=30ba0a882f0c061176ba14dbf86d3d6fad096c02;p=debian%2Fopenrocket

diff --git a/core/src/net/sf/openrocket/simulation/customexpression/IndexExpression.java b/core/src/net/sf/openrocket/simulation/customexpression/IndexExpression.java
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index 00000000..6fb084de
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+++ b/core/src/net/sf/openrocket/simulation/customexpression/IndexExpression.java
@@ -0,0 +1,56 @@
+package net.sf.openrocket.simulation.customexpression;
+
+import java.util.List;
+
+import de.congrace.exp4j.Calculable;
+import de.congrace.exp4j.Variable;
+import net.sf.openrocket.document.OpenRocketDocument;
+import net.sf.openrocket.logging.LogHelper;
+import net.sf.openrocket.simulation.customexpression.CustomExpression;
+import net.sf.openrocket.simulation.FlightDataType;
+import net.sf.openrocket.simulation.SimulationStatus;
+import net.sf.openrocket.startup.Application;
+import net.sf.openrocket.util.LinearInterpolator;
+
+public class IndexExpression extends CustomExpression {
+
+	FlightDataType type;
+	private static final LogHelper log = Application.getLogger();
+	
+	public IndexExpression(OpenRocketDocument doc, String indexText, String typeText){
+		super(doc);
+		
+		setExpression(indexText);
+		this.setName("");
+		this.setSymbol(typeText);
+	}
+	
+	@Override
+	public Variable evaluate(SimulationStatus status){
+		
+		Calculable calc = buildExpression();
+		if (calc == null){
+			return new Variable("Unknown");
+		}
+		
+		// From the given datatype, get the time and function values and make an interpolator
+
+		//Note: must get in a way that flight data system will figure out units. Otherwise there will be a type conflict when we get the new data.
+		FlightDataType type = FlightDataType.getType(null, getSymbol(), null);  
+				
+		List<Double> data = status.getFlightData().get(type);
+		List<Double> time = status.getFlightData().get(FlightDataType.TYPE_TIME);
+		LinearInterpolator interp = new LinearInterpolator(time, data); 
+		
+		// Evaluate this expression to get the t value
+		try{
+			double tvalue = calc.calculate().getDoubleValue();
+			return new Variable(hash(), interp.getValue( tvalue ) );
+		}
+		catch (java.util.EmptyStackException e){
+			log.user("Unable to calculate time index for indexed expression "+getExpressionString()+" due to empty stack exception");
+			return new Variable("Unknown");
+		}
+		
+	}
+}