SumFunction.java

/*
* Copyright (c) 2005, Graph Builder
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* modification, are permitted provided that the following conditions
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package com.graphbuilder.math.func;

/**
The sum function.
*/
public class SumFunction implements Function {

	public SumFunction() {}

	/**
	Returns the sum of the values in the array from [0, numParam).
	*/
	public double of(double[] d, int numParam) {
		double sum = 0;

		for (int i = 0; i < numParam; i++)
			sum += d[i];

		return sum;
	}

	/**
	Returns true for 1 or more parameters, false otherwise.
	*/
	public boolean acceptNumParam(int numParam) {
		return numParam > 0;
	}

	public String toString() {
		return "sum(x1, x2, ..., xn)";
	}
}