manips.cpp

Code

/*
 *   manips.cpp
 *   CIS 250
 *   David Klick
 *   2014-01-04
 *
 *   Demonstration of some stream manipulators
 */

#include <iostream>
#include <iomanip>
using std::cin;
using std::cout;
using std::endl;
using std::setfill;
using std::setw;
using std::left;
using std::right;
using std::showpos;
using std::noshowpos;
using std::internal;
using std::hex;
using std::uppercase;
using std::showbase;
using std::noshowbase;
using std::setprecision;
using std::dec;
using std::showpoint;
using std::fixed;
using std::boolalpha;
using std::setiosflags;
using std::ios;
using std::scientific;

int main(int argc, char* argv[]) {
    int i = 17;
    double x = 98.7654321;
    double y = 72.0;
    bool truth = true;

    // set width and fill character
    cout << setfill('*') << setw(5) << i << endl;

    // left justification
    cout << left << setw(5) << i << endl;

    // show sign even if positive
    cout << right << setw(5) << showpos << i << endl;

    // do padding between sign and value
    cout << setw(5) << internal << i << endl;

    // do padding between sign and value
    cout << setw(5) << noshowpos << i << endl;

    // uppercase hex output with 0 fill
    cout << setw(5) << hex << uppercase << setfill('0') << i << endl;

    // prepend base indicator
    cout << setw(5) << showbase << i << noshowbase << endl;

    // display fp number in field 8 wide with 2 decimal positions
    //   this doesn't do quite what is expected - the setprecision is
    //   interpreted as significant digits instead of decimal positions
    //   because the display format internally is scientific
    cout << dec << setw(8) << setprecision(2) << x << endl;

    // show number in fixed format
    cout << setw(8) << fixed << x << endl;

    // display a number with no significant digits after decimal
    cout << setw(8) << setprecision(0) << y << endl;

    // force display of decimal point
    cout << setw(8) << showpoint << y << endl;

    // display boolean value as both number and as text
    cout << truth << "   " << boolalpha << truth << endl;

    // demonstrate difference of setprecision for fixed/scientific
    //   format vs. general format
    cout << fixed << setprecision(5) << x << endl;
    cout << setiosflags(ios::fixed | ios::scientific) << x << endl;

    // the base manipulators can also be used for input
    cout << "Enter a number in hex: ";
    cin >> hex >> i;
    cout << i << endl;

    return 0;
}

/*
    Sample output:

    ***17
    17***
    **+17
    +**17
    ***17
    00011
    0X011
    00000099
    00098.77
    00000072
    0000072.
    1   true
    98.76543
    98.765
    Enter a number in hex: 1a5
    421
*/