/*
* 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>StdevP</code> builtin MDX function, and its alias
* <code>StddevP</code>.
*
* @author jhyde
* @since Mar 23, 2006
*/
class StdevPFunDef extends AbstractAggregateFunDef {
static final Resolver StdevpResolver =
new ReflectiveMultiResolver(
"StdevP",
"StdevP(<Set>[, <Numeric Expression>])",
"Returns the standard deviation of a numeric expression evaluated over a set (biased).",
new String[]{"fnx", "fnxn"},
StdevPFunDef.class);
static final Resolver StddevpResolver =
new ReflectiveMultiResolver(
"StddevP",
"StddevP(<Set>[, <Numeric Expression>])",
"Alias for StdevP.",
new String[]{"fnx", "fnxn"},
StdevPFunDef.class);
public StdevPFunDef(FunDef dummyFunDef) {
super(dummyFunDef);
}
public Calc compileCall(ResolvedFunCall call, ExpCompiler compiler) {
final ListCalc listCalc =
compiler.compileList(call.getArg(0));
final Calc calc =
call.getArgCount() > 1
? compiler.compileScalar(call.getArg(1), true)
: new ValueCalc(call);
return new AbstractDoubleCalc(call, new Calc[] {listCalc, calc}) {
public double evaluateDouble(Evaluator evaluator) {
final int savepoint = evaluator.savepoint();
try {
evaluator.setNonEmpty(false);
TupleList list = evaluateCurrentList(listCalc, evaluator);
final double stdev =
(Double) stdev(
evaluator, list, calc, true);
return stdev;
} finally {
evaluator.restore(savepoint);
}
}
public boolean dependsOn(Hierarchy hierarchy) {
return anyDependsButFirst(getCalcs(), hierarchy);
}
};
}
}
// End StdevPFunDef.java