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### 7.7 Operators

The operators are pretty much the same as in the C language. The common ones are:

Arithmetic
  `+` (add)
  `-` (subtract)
  `*` (multiply)
  `/` (divide)
  `%` (modulus)
Logical
  `!` (not)
  `&&` (and)
  `||` (or)
  `^` (exclusive-or)
  `==` (numeric identity)
  `!=` (numeric non-identity)
  `<` (less than)
  `>` (greater than)
  `<=` (less than or equal)
  `>=` (greater than or equal)
  Note: the comparison operators `<`, `>`, `<=`, `>=`, `==` and `!=` can be used on Strings as well as numeric values with common-sense meanings (comparison based on Locale-specific string ordering); this is a feature of the JEL-based expression language even though it doesn't work like that in the Java language itself.
Bitwise
  `&` (and)
  `|` (or)
  `^` (exclusive-or)
  `<<` (left shift)
  `>>` (right shift)
  `>>>` (logical right shift)
Numeric Typecasts
  `(byte)` (numeric -> signed byte)
  `(short)` (numeric -> 2-byte integer)
  `(int)` (numeric -> 4-byte integer)
  `(long)` (numeric -> 8-byte integer)
  `(float)` (numeric -> 4-byte floating point)
  `(double)` (numeric -> 8-byte floating point)
  Note you may find the numeric conversion functions in the Maths class described in Appendix B.1 below more convenient for numeric conversions than these.
Other
  `+` (string concatenation)
  `[]` (array dereferencing - first element is zero)
  `?:` (conditional switch)
  `instanceof` (class membership)

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TOPCAT - Tool for OPerations on Catalogues And Tables
Starlink User Note253
TOPCAT web page: http://www.starlink.ac.uk/topcat/
Author email: m.b.taylor@bristol.ac.uk
Mailing list: topcat-user@jiscmail.ac.uk