setw also works with floating-point numbers (remember that a decimal point
is a character)
If you dont want numbers to appear in scientific notation, use fixed.
If you want whole numbers printed with a .0 appended, use showpoint.
If you want to control the number of decimal places that are displayed, use setprecision(n), where n is the number of decimal places
desired. Unlike setw, setprecision stays in effect until you
explicitly change it.