Mass Vector

A point mass consists of a 3-D location and an associated mass, such as

Location: (6, 0, 2) Mass: 3g

In a system of point masses, let p 1 , p 2 …….p n be the n 3-D points and m 1 , m 2 ……. m n be their associated masses. If m is the sum of the masses, the center of gravity C is calculated as

C=1/m(m1p1+m2p2+......+mnpn)

Write a program that repeatedly inputs point-mass system data sets from an input file until an input operation fails. For each data set, display the location matrix, the mass vector, n , and the center of gravity. Each data set includes a location matrix (a matrix in which each row is a point), a one-dimensional array of masses, and the number of point masses, n . Allow n to vary from 3 to 10.

Sample Data File

4

5 -4 3 2

4 3 -2 5

-4 -3 -1 2

-9 8 6 1

This sample should be stored as:

location 5 -4 3

4 3 -2

-4 -3 -1

-9 8 6

mass 2

5

2

1

n 4

Your main function should repeatedly input and process data sets from an input file until end of file is encountered. For each point-mass system data set, display the location matrix, the mass vector, n , and the center of gravity. Implement at least the following functions:

fget_point_mass : Takes an open input file and a maximum value for n as parameters and fills a two-dimensional array output parameter with a location matrix and a one-dimensional array output parameter with a mass vector from the data file. Returns as function value the actual value of n . center_grav : Takes a location matrix, mass vector, and n value as parameters, and calculates and returns as the function value the center of gravity of the system. fwrite_point_mass : Takes an open output file and the location matrix, mass vector, and n value of a point-mass system as parameters and writes the system to the file with meaningful labels.