package org.boris.expr.function.excel;
import org.boris.expr.Expr;
import org.boris.expr.ExprArray;
import org.boris.expr.ExprDouble;
import org.boris.expr.ExprError;
import org.boris.expr.ExprEvaluatable;
import org.boris.expr.ExprException;
import org.boris.expr.ExprInteger;
import org.boris.expr.ExprMissing;
import org.boris.expr.ExprNumber;
import org.boris.expr.ExprString;
import org.boris.expr.function.AbstractFunction;
public class AVEDEV extends AbstractFunction
{
public Expr evaluate(Expr[] args) throws ExprException {
assertMinArgCount(args, 1);
double[] values = { 0, 0 };
for (Expr a : args)
AVERAGE.eval(a, values, true);
if (values[1] == 0) {
return ExprError.NUM;
}
double average = values[0] / values[1];
values[0] = values[1] = 0;
for (Expr a : args)
eval(a, average, values, true);
return new ExprDouble(values[0] / values[1]);
}
public static void eval(Expr a, double average, double[] values,
boolean strict) throws ExprException {
if (a instanceof ExprEvaluatable)
a = ((ExprEvaluatable) a).evaluate();
if (a == null)
return;
if (a instanceof ExprMissing)
return;
if (a instanceof ExprString) {
if (strict)
throw new ExprException("Unexpected argument for AVERAGE: " + a);
else
return;
}
if (a instanceof ExprDouble || a instanceof ExprInteger) {
double d = ((ExprNumber) a).doubleValue();
values[0] += Math.abs(average - d);
values[1] += 1;
return;
}
if (a instanceof ExprArray) {
ExprArray arr = (ExprArray) a;
int rows = arr.rows();
int cols = arr.columns();
for (int i = 0; i < rows; i++) {
for (int j = 0; j < cols; j++) {
eval(arr.get(i, j), average, values, false);
}
}
return;
}
throw new ExprException("Unexpected argument for AVEDEV: " + a);
}
}