Zoo tutorials: [ SQL | Linux | XML ]
ProgZoo: [ Java | C# | VB | C++ | Perl ]
Log in

A Gentle Introduction to
Programming

Converting between number types

 

Data types

Converting between number types

When converting from a floating point number to an integer there is likely to be a loss of precision - for example 3.1 will become 3.

When converting from an integer to a floating point there is no such danger.

1. [ Java ] integer to floating point


Big

Not much can go wrong. The conversion is automatic.

However notice:

  • the calculation i/10 is performed as an integer calculation and gives 123.0
  • the calculation i/10.0 is performed as a floating point calculation and gives 123.4

2. [ Java ] Rounding to an integer


Big

We can use Math.round to convert a double to a long or a float to an int.

We can recast explicitly and have the fractional part of the number discarded.