# ipe::Linear Class Reference
Ipe Geometry

Linear transformation in the plane (2x2 matrix). More...

`#include <ipegeo.h>`

List of all members.

## Public Member Functions

- Linear ()
- Linear (Angle angle)
- Linear (double m11, double m21, double m12, double m22)
- Linear (String str)
- Linear inverse () const
- bool isIdentity () const
- Vector operator* (const Vector &rhs) const
- bool operator== (const Linear &rhs) const
- double determinant () const

## Public Attributes

- double a [4]

## Related Functions

(Note that these are not member functions.)

- Stream & operator<< (Stream &stream, const Linear &rhs)
- Linear operator* (const Linear &lhs, const Linear &rhs)

## Detailed Description

Linear transformation in the plane (2x2 matrix).

## Constructor & Destructor Documentation

ipe::Linear::Linear | ( |  | ) | `[inline]`

Create identity matrix.

Linear::Linear | ( | Angle | angle | ) | `[explicit]`

Create matrix representing a rotation by angle.

ipe::Linear::Linear | ( | double | m11,
|  | double | m21,
|  | double | m12,
|  | double | m22
| ) |  | `[inline, explicit]`

Create linear matrix with given coefficients.

Linear::Linear | ( | String | str | ) | `[explicit]`

Parse string.

## Member Function Documentation

Linear Linear::inverse | ( |  | ) | const

Return inverse.

bool ipe::Linear::isIdentity | ( |  | ) | const`[inline]`

Is this the identity matrix?

Vector operator* | ( | const Vector & | rhs | ) | const`[inline]`

Linear matrix times vector.

Matrix times vector.

bool ipe::Linear::operator== | ( | const Linear & | rhs | ) | const`[inline]`

Check for equality of two linear matrices.

double ipe::Linear::determinant | ( |  | ) | const`[inline]`

Return determinant of a linear matrix.

## Friends And Related Function Documentation

Stream & operator<< | ( | Stream & | stream,
|  | const Linear & | rhs
| ) |  | `[related]`

Linear operator* | ( | const Linear & | lhs,
|  | const Linear & | rhs
| ) |  | `[related]`

Linear matrix multiplication.

## Member Data Documentation

double ipe::Linear::a[4]

The documentation for this class was generated from the following files:

- ipegeo.h
- ipegeo.cpp