Formating of Program Using cout

#include <iostream>

#include <iomanip>

 

using namespace std;

 

int main(void)

{long m=56, n=-1;

double x=12.56,y = .123456789e-4;

 

cout<<"12345678901234567890123456789012345678901234567890" <<endl;

 

//six significant figures by default are displayed

cout<<"six significant figures by default are displayed; values run together\n";

cout<<x;

cout<<y;

cout<<endl;

 

//setw establishes a field width for the value immediately following it

cout

<<"setw establishes a field width for the value immediately following it\n";

cout<<setw(10)<<x;

cout<<setw(20)<<y ;

cout<<endl;

 

//setprecision establishes the precision until it is changed.

//setprecision by itself sets the total number of digits to be displayed

 

cout<<"setprecision of 8 sets total number of digits to be displayed\n";

 

cout<<setprecision(8)<<x<<'\n';

cout<<y ; //setprecision of 8 still in play

cout<<endl;

 

 

cout<<"setprecision of 4\n";

 

cout<<setw(20)<<setprecision(4)<<x<<'\n';

cout<<setw(20)<<y ; //setprecision of 4 still in play

cout<<endl;

cout<<endl;

 

//the exact format can be controled by using setiosflags.

//it applies until changed.

//the number of decimal places to be printed can be set by using

//setiosflags(ios::fixed) in conjunction with setprecision.

//together the meaning of setprecion is to set the number of decimal

//places to be printed.

 

cout<<"the exact format can be controled by using setiosflags(ios::fixed)\n";

cout <<"setprecision of 5 now in play"<<endl;

 

cout<<setw(20)<<setprecision(5)<< setiosflags(ios::fixed)<<x<<'\n';

cout<<setw(20)<<y ; //setprecision of 5 still in play

cout<<endl;

cout<<endl;

cout << "or \n";

cout<<setw(20)<< fixed <<x<<'\n';

cout<<endl;

cout<<endl;

 

//you can return to scientific format when you want

cout<<

"return to scientific when you want\nprecison here has returned to default\n";

cout<<setw(20)<< scientific <<y<<'\n';

 

 

// print integers

cout<<"print integers\n";

cout<<setw(10)<< n <<'\n';

cout<<setw(10)<< m <<'\n';

 

// print integers with justification

cout<<" print integers with justification\n";

cout<<setw(10)<< setiosflags(ios::left) <<n <<'\n';

cout<<setw(10)<< right<< m <<'\n';

 

//you can find out the amount of storage associated with a given type

cout << "the sizeof(long) is "<< sizeof(long)<<endl;

 

 

// you can get integers printed in alternate bases.

cout <<"m is "<< m << " ; m in hex is "<< hex<< setw(20) << m <<endl;

cout <<dec <<"n is "<< n << " ; n in hex is "<< hex<< setw(20) << n <<endl;

 

cout<<" m and n in octal are ";

cout << oct<< setw(20) << m << setw(20)<< n;

 

 

cout<<endl;

return 0;

}

 

[pt@cs aix]$ c++ cout2.cpp

[pt@cs aix]$ a.out

12345678901234567890123456789012345678901234567890

six significant figures by default are displayed; values run together

12.561.23457e-05

setw establishes a field width for the value immediately following it

12.56 1.23457e-05

setprecision of 8 sets total number of digits to be displayed

12.56

1.2345679e-05

setprecision of 4

12.56

1.235e-05

 

the exact format can be controled by using setiosflags(ios::fixed)

setprecision of 5 now in play

12.56000

0.00001

 

or

12.56000

 

 

return to scientific when you want

precison here has returned to default

1.23457e-05

print integers

-1

56

print integers with justification

-1

56

the sizeof(long) is 4

m is 56 ; m in hex is 38

n is -1 ; n in hex is ffffffff

m and n in octal are 70 37777777777