Class Sum

    • Constructor Detail

      • Sum

        public Sum()
        Create a Sum instance
      • Sum

        public Sum​(Sum original)
            throws NullArgumentException
        Copy constructor, creates a new Sum identical to the original
        Parameters:
        original - the Sum instance to copy
        Throws:
        NullArgumentException - if original is null
    • Method Detail

      • getN

        public long getN()
        Returns the number of values that have been added.
        Specified by:
        getN in interface StorelessUnivariateStatistic
        Returns:
        the number of values.
      • evaluate

        public double evaluate​(double[] values,
                               double[] weights,
                               int begin,
                               int length)
                        throws MathIllegalArgumentException
        The weighted sum of the entries in the specified portion of the input array, or 0 if the designated subarray is empty.

        Throws MathIllegalArgumentException if any of the following are true:

        • the values array is null
        • the weights array is null
        • the weights array does not have the same length as the values array
        • the weights array contains one or more infinite values
        • the weights array contains one or more NaN values
        • the weights array contains negative values
        • the start and length arguments do not determine a valid array

        Uses the formula,

            weighted sum = Σ(values[i] * weights[i])
         

        Parameters:
        values - the input array
        weights - the weights array
        begin - index of the first array element to include
        length - the number of elements to include
        Returns:
        the sum of the values or 0 if length = 0
        Throws:
        MathIllegalArgumentException - if the parameters are not valid
        Since:
        2.1
      • evaluate

        public double evaluate​(double[] values,
                               double[] weights)
                        throws MathIllegalArgumentException
        The weighted sum of the entries in the the input array.

        Throws MathIllegalArgumentException if any of the following are true:

        • the values array is null
        • the weights array is null
        • the weights array does not have the same length as the values array
        • the weights array contains one or more infinite values
        • the weights array contains one or more NaN values
        • the weights array contains negative values

        Uses the formula,

            weighted sum = Σ(values[i] * weights[i])
         

        Parameters:
        values - the input array
        weights - the weights array
        Returns:
        the sum of the values or Double.NaN if length = 0
        Throws:
        MathIllegalArgumentException - if the parameters are not valid
        Since:
        2.1
      • copy

        public static void copy​(Sum source,
                                Sum dest)
                         throws NullArgumentException
        Copies source to dest.

        Neither source nor dest can be null.

        Parameters:
        source - Sum to copy
        dest - Sum to copy to
        Throws:
        NullArgumentException - if either source or dest is null