# struct Geode::Matrix4x3(T)

## Overview

Matrix with 4 rows and 3 columns. Provides a rectangular array of scalars of the same type.

T is the scalar type. Indices i and j refer to the zero-based row and column index respectively. Unless noted otherwise, all operations are in row-major order.

## Defined in:

geode/matrices/matrix4.cr

## Macro Summary

• [](*rows)

Constructs a matrix with existing elements.

## Constructor Detail

def self.new(matrix : CommonMatrix(T, 4, 3)) #

Copies contents from another matrix.

def self.new(&) #

Creates a new matrix by iterating through each element.

Yields the indices (i and j) for the matrix element. The block should return the value to use for the corresponding element.

``Matrix4x3.new { |i, j| i * 10 + j }``

def self.new(rows : Indexable(Indexable(T))) #

Creates a new matrix from nested collections.

The size of rows must be 4. Each row of elements in rows must have a size of 3.

def self.new(elements : Indexable(T)) #

Creates a new matrix from a flat collection of elements.

The size of elements must be equal to 4 x 3 (12). Items in elements are consumed in row-major order.

def self.zero : self #

Creates a matrix filled with zeroes.

## Class Method Detail

def self.[](row_0 : Indexable, row_1 : Indexable, row_2 : Indexable, row_3 : Indexable) #

Constructs a matrix with existing elements.

The type of the elements is specified by the type parameter. Each value is cast to the type T.

## Instance Method Detail

def &*(other : CommonMatrix(U, 3, P)) : Matrix forall U, P #

Multiplies this matrix by another.

The other matrix's row count (M) must be equal to this matrix's column count (N). Produces a new matrix with the row count from this matrix and the column count from other. Matrices can be of any size and type as long as this condition is met.

Values will wrap instead of overflowing and raising an error.

def &*(other : Matrix3x1) : Matrix4x1 #

Multiplies this matrix by another.

The other matrix's row count (M) must be equal to this matrix's column count (N). Produces a new matrix with the row count from this matrix and the column count from other. Matrices can be of any size and type as long as this condition is met.

Values will wrap instead of overflowing and raising an error.

def &*(other : Matrix3x2) : Matrix4x2 #

Multiplies this matrix by another.

The other matrix's row count (M) must be equal to this matrix's column count (N). Produces a new matrix with the row count from this matrix and the column count from other. Matrices can be of any size and type as long as this condition is met.

Values will wrap instead of overflowing and raising an error.

def &*(other : Matrix3x3) : Matrix4x3 #

Multiplies this matrix by another.

The other matrix's row count (M) must be equal to this matrix's column count (N). Produces a new matrix with the row count from this matrix and the column count from other. Matrices can be of any size and type as long as this condition is met.

Values will wrap instead of overflowing and raising an error.

def &*(other : Matrix3x4) : Matrix4x4 #

Multiplies this matrix by another.

The other matrix's row count (M) must be equal to this matrix's column count (N). Produces a new matrix with the row count from this matrix and the column count from other. Matrices can be of any size and type as long as this condition is met.

Values will wrap instead of overflowing and raising an error.

def *(other : CommonMatrix(U, 3, P)) : Matrix forall U, P #

Multiplies this matrix by another.

The other matrix's row count (M) must be equal to this matrix's column count (N). Produces a new matrix with the row count from this matrix and the column count from other. Matrices can be of any size and type as long as this condition is met.

def *(other : Matrix3x1) : Matrix4x1 #

Multiplies this matrix by another.

The other matrix's row count (M) must be equal to this matrix's column count (N). Produces a new matrix with the row count from this matrix and the column count from other. Matrices can be of any size and type as long as this condition is met.

def *(other : Matrix3x2) : Matrix4x2 #

Multiplies this matrix by another.

The other matrix's row count (M) must be equal to this matrix's column count (N). Produces a new matrix with the row count from this matrix and the column count from other. Matrices can be of any size and type as long as this condition is met.

def *(other : Matrix3x3) : Matrix4x3 #

Multiplies this matrix by another.

The other matrix's row count (M) must be equal to this matrix's column count (N). Produces a new matrix with the row count from this matrix and the column count from other. Matrices can be of any size and type as long as this condition is met.

def *(other : Matrix3x4) : Matrix4x4 #

Multiplies this matrix by another.

The other matrix's row count (M) must be equal to this matrix's column count (N). Produces a new matrix with the row count from this matrix and the column count from other. Matrices can be of any size and type as long as this condition is met.

def a : T #

Retrieves the element at (0, 0)

def b : T #

Retrieves the element at (0, 1)

def c : T #

Retrieves the element at (0, 2)

def d : T #

Retrieves the element at (1, 0)

def e : T #

Retrieves the element at (1, 1)

def f : T #

Retrieves the element at (1, 2)

def g : T #

Retrieves the element at (2, 0)

def h : T #

Retrieves the element at (2, 1)

def i : T #

Retrieves the element at (2, 2)

def j : T #

Retrieves the element at (3, 0)

def k : T #

Retrieves the element at (3, 1)

def l : T #

Retrieves the element at (3, 2)

def map(& : T -> U) : Matrix4x3 forall U #

Returns a new matrix with elements mapped by the given block.

def sub(i : Int, j : Int) : Matrix3x2(T) #

Returns a smaller matrix by removing a row and column.

The row indicated by i and the column indicated by j are removed in the resulting matrix.

def to_slice : Slice(T) #

Returns a slice that points to the elements in this matrix.

NOTE The returned slice is only valid for the caller's scope and sub-calls. The slice points to memory on the stack, it will be invalid after the caller returns.

def to_unsafe : Pointer(T) #

Returns a pointer to the data for this matrix.

The elements are tightly packed and ordered consecutively in memory.

NOTE The returned pointer is only valid for the caller's scope and sub-calls. The pointer refers to memory on the stack, it will be invalid after the caller returns.

def transpose : Matrix3x4(T) #

Returns a new matrix that is transposed from this one.

def unsafe_fetch(index : Int) #

Retrieves the scalar value of the component at the given index, without checking size boundaries.

End-users should never invoke this method directly. Instead, methods like `#[]` and `#[]?` should be used.

This method should only be directly invoked if the index is certain to be in bounds.

def unsafe_fetch_column(j : Int) : Vector4(T) #
Description copied from module Geode::CommonMatrix(T, 4, 3)

Retrieves the column at the specified index.

Returns the elements as a vector. The vector will have a size equal to the number of rows in this matrix. This method does not perform any bounds checks. It should only be used if the indices are guaranteed to be in bounds.

``````matrix = Matrix[[1, 2, 3], [4, 5, 6]]
matrix.unsafe_fetch_column(1) # => (2, 5)``````

def unsafe_fetch_row(i : Int) : Vector3(T) #
Description copied from module Geode::CommonMatrix(T, 4, 3)

Retrieves the row at the specified index.

Returns the elements as a vector. The vector will have a size equal to the number of columns in this matrix. This method does not perform any bounds checks. It should only be used if the indices are guaranteed to be in bounds.

``````matrix = Matrix[[1, 2, 3], [4, 5, 6]]
matrix.unsafe_fetch_row(1) # => (4, 5, 6)``````

## Macro Detail

macro [](*rows) #

Constructs a matrix with existing elements.

The type of the elements is derived from the type of each argument. The size of rows must be 4 and the size of each row must be 3.