Number Types

The number types int, float, and double provided by C++ are only crude approximations of the mathematical counterparts: ints can overflow, the arithmetic for floats and doubles incurs rounding errors.

In some areas, especially computational geometry and network algorithms, it is very important to have exact results or, at least, to know bounds on the error of the result.

Examples for the dangers of floating point arithmetic

Therefore, LEDA provides different number types that solve the problem of inexact arithmetic:

Data types that always give mathematically correct answers:

• Integers of Arbitrary Length
• Rational Numbers
• Algebraic Real Numbers

Data type with rounding, but the rounding precision can be arbitrarily large:

• Big Floatingpoint Numbers

Data types for improving the speed of an exact arithmetic type:

• Floating Point Filter
• Interval Arithmetic

Data types for linear algebra:

• Double Valued Vectors and Matrices
• Vectors and Matrices with Integer Entries
• Rational Vectors

Functions of numerical analysis, like computation of minima/maxima, integration, and root finding.

See also:

Simple Data Types

Graph Types

Graph Algorithms

Geometry

Geometry Algorithms

Windows and Panels

GraphWin

GeoWin