Formatting Output

• setw(int)
  • #include <iomanip>
  • cout << setw(4) << 22;
  • The next item output will take at least the given number of spaces.
  • This is only a temporary change to the stream.
  • This is a way to right align the output.
  • Experiemnt with this.
  • We normally show this with a constant, but any int expression will do.
• By default, the stream trys to show floating point numbers in a resonalbe way.
• But you can change to give what you want.
• Floating Point stream manipulators
  • These change the state of the stream until it is changed again.
  • Note, mixing these have in the past produced strange behavior
  • showpoint
    • cout << showpoint
    • By default floating point numbers will only have a decimal point if required.
    • If it contains an int for example.
    • This will cause the decimal point to be displayed.

    • f = 8.0;
      cout << f << showpoint << " with showpoint " << f << endl;
      
      Produces
      8 with showpoint 8.00000
      
      	      

  • fixed, scientific
    • Show all floating point numbers in either fixed or scientific notation.
  • setprecision(int )
    • Sets the decimal precision for the stream.