/*
* This software is subject to the terms of the Eclipse Public License v1.0
* Agreement, available at the following URL:
* http://www.eclipse.org/legal/epl-v10.html.
* You must accept the terms of that agreement to use this software.
*
* Copyright (c) 2002-2013 Pentaho Corporation.. All rights reserved.
*/
package mondrian.olap.fun;
import mondrian.calc.*;
import mondrian.calc.impl.AbstractDoubleCalc;
import mondrian.calc.impl.ValueCalc;
import mondrian.mdx.ResolvedFunCall;
import mondrian.olap.*;
/**
* Definition of the <code>Covariance</code> and
* <code>CovarianceN</code> MDX functions.
*
* @author jhyde
* @since Mar 23, 2006
*/
class CovarianceFunDef extends FunDefBase {
static final ReflectiveMultiResolver CovarianceResolver =
new ReflectiveMultiResolver(
"Covariance",
"Covariance(<Set>, <Numeric Expression>[, <Numeric Expression>])",
"Returns the covariance of two series evaluated over a set (biased).",
new String[]{"fnxn", "fnxnn"},
CovarianceFunDef.class);
static final MultiResolver CovarianceNResolver =
new ReflectiveMultiResolver(
"CovarianceN",
"CovarianceN(<Set>, <Numeric Expression>[, <Numeric Expression>])",
"Returns the covariance of two series evaluated over a set (unbiased).",
new String[]{"fnxn", "fnxnn"},
CovarianceFunDef.class);
private final boolean biased;
public CovarianceFunDef(FunDef dummyFunDef) {
super(dummyFunDef);
this.biased = dummyFunDef.getName().equals("Covariance");
}
public Calc compileCall(ResolvedFunCall call, ExpCompiler compiler) {
final ListCalc listCalc =
compiler.compileList(call.getArg(0));
final Calc calc1 =
compiler.compileScalar(call.getArg(1), true);
final Calc calc2 =
call.getArgCount() > 2
? compiler.compileScalar(call.getArg(2), true)
: new ValueCalc(call);
return new AbstractDoubleCalc(call, new Calc[] {listCalc, calc1, calc2})
{
public double evaluateDouble(Evaluator evaluator) {
TupleList memberList = listCalc.evaluateList(evaluator);
final int savepoint = evaluator.savepoint();
try {
evaluator.setNonEmpty(false);
final double covariance =
(Double) covariance(
evaluator,
memberList,
calc1,
calc2,
biased);
return covariance;
} finally {
evaluator.restore(savepoint);
}
}
public boolean dependsOn(Hierarchy hierarchy) {
return anyDependsButFirst(getCalcs(), hierarchy);
}
};
}
}
// End CovarianceFunDef.java