CS 99

Summer 2002: Lab 3 07.11

Solutions

 
1. Geometric Mean
%GeoMean.m

%Name: Trinity
%CUID: 303000
%Date: 11 July 2002
 
%clear workspace variables

clear all;


%Prompt user for values
disp(‘Enter a sequence of numbers, terminated by a negative value.’);
val = input('> ');
 
%initialize variables

count = 0;  %number of values entered by user
prod = 1; %running product of values
 
%update count and prod when input value is non-negative
while val >= 0 

 count = count + 1; 
 prod = prod*val;

 %prompt user for next value
 val = input('> ');
end
 
%report results
if count > 0
 gMean = prod^(1/count);
 disp(['The geometric mean of the values is ' num2str( gMean ) ] );
else
 disp('No input data given');
end
 
2. Not a perfect square


%clear workspace variables

clear all;


%counter variable

n = 1;
%true if we find an integral value for which the relation is a perfect square, false otherwise

foundSqr = 0;
 
while n <= 10000
 val = floor( n + sqrt(n) + 1/2 );
 %a number is a perfect square if its square root is an integer
 if floor( sqrt( val ) ) == ceil( sqrt( val ) )
 disp([ num2str( val ) ' is a perfect square! Whoa.' ]);
 foundSqr = 1;
 end
 n = n + 1;
end
 
%report results
if ~foundSqr
 disp('No perfect squares found');
end