JEP is a Java API for parsing and evaluating mathematical expressions.
With this library you can allow your users to enter an arbitrary
formula as a string, and instantly evaluate it. JEP supports user
defined variables, constants, and functions. A number of common
mathematical functions and constants are included.

Features:
   * Small size (only 75KB as jar archive)
   * Supports Boolean expressions (!, &&, ||, <, >, !=, ==, >=, and
<=)
   * Fast evaluation (the expression can be evaluated quickly for
different variable values)
   * Includes common math functions
   * Extendable through user defined functions
   * Predefined constants such as 'pi' and 'e'
   * Support for strings, complex numbers, and vectors
   * Support for implicit multiplication (allows use of expressions
such as "3x" instead of "3*x")
   * Allows choice between declared and undeclared variables
   * Java 1.2 compatible (cross-compiled with Sun JDK 1.2.2)
   * Supports Unicode characters (including Greek symbols)
   * Includes JavaCC grammar from which the main classes are generated

Changes in this release:
   * Fixed bug 1046349: bug in sum()
   * Fixed broken links in documentation
   * Fixed bug 1051988: JEPTester falsely reports "No errors"
   * Fixed documentation error 1358815: if - function is documented
wrong
   * Added more tests for sum function
   * Updated build.xml to work with 1.5 JVMs