# Release notes§

This lists the change brought by all major releases. The corresponding source code may be found based on tags on github.

### Version 0.16§

All dependencies have been updated to their latest versions.

#### Modified§

- Adjust
`UnitQuaternion`

s,`Rotation3`

s, and`Rotation2`

s generated from the`Standard`

distribution to be uniformly distributed.

#### Added§

- Add a feature
`stdweb`

to activate the dependency feature`rand/stdweb`

. - Add blas-like methods
`.imin()`

and`.imax()`

that return the index of the minimum and maximum entry of a vector. - Add construction of a
`Point`

from an array by implementing the`From`

trait. - Add support for generating uniformly distributed random unit column vectors using the
`Standard`

distribution.

### Version 0.15§

The most notable change of this release is the support for using part of the library without the rust standard
library (i.e. it supports `#![no_std]`

). See the corresponding documentation.

#### Modified§

- Rename the
`core`

module to`base`

to avoid conflicts with the`core`

crate implicitly imported when`#![no_std]`

is enabled. - Constructors of the
`MatrixSlice*`

types have been renamed from`new_*`

to`from_slice_*`

. This was necessary to avoid the`incoherent_fundamental_impls`

lint that is going to become a hard error.

#### Added§

- Add
`UnitQuaternion`

constructor`::new_eps(...)`

and`::from_scaled_axis_eps(...)`

that return the identity if the magnitude of the input axisangle is smaller than the epsilon provided. - Add methods
`.rotation_between_axis(...)`

and`.scaled_rotation_between_axis(...)`

to`UnitComplex`

to compute the rotation matrix between two 2D**unit**vectors. - Add methods
`.axis_angle()`

to`UnitComplex`

and`UnitQuaternion`

in order to retrieve both the unit rotation axis and the rotation angle simultaneously. - Add functions to construct a random matrix with a user-defined distribution:
`::from_distribution(...)`

.

### Version 0.14§

#### Modified§

- Allow the
`Isometry * Unit<Vector>`

multiplication.

#### Added§

- Add blas-like operations:
`.quadform(...)`

and`.quadform_tr(...)`

to compute respectively the quadratic forms`self = alpha * A.transpose() * B * A + beta * self`

and`alpha * A * B * A.transpose() + beta * self`

. Here,`A, B`

are matrices with`B`

square, and`alpha, beta`

are reals. - Add blas-like operations:
`.gemv_tr(...)`

that behaves like`.gemv`

except that the provided matrix is assumed to be transposed. - Add blas-like operations:
`cmpy, cdpy`

for component-wise multiplications and division with scalar factors: -`self <- alpha * self + beta * a * b`

-`self <- alpha * self + beta / a * b`

`.cross_matrix()`

returns the cross-product matrix of a given 3D vector, i.e., the matrix`M`

such that for all vector`v`

we have`M * v == self.cross(&v)`

.`.iamin()`

that returns the index of the vector entry with smallest absolute value.- The
`mint`

feature that can be enabled in order to allow conversions from and to types of the mint crate. - Aliases for matrix and vector slices. Their are named by adding
`Slice`

before the dimension numbers, i.e., a 3x5 matrix slice with dimensions known at compile-time is called`MatrixSlice3x5`

. A vector slice with dimensions unknown at compile-time is called`DVectorSlice`

. - Add functions for constructing matrix slices from a slice
`&[N]`

, e.g.,`MatrixSlice2::new(...)`

and`MatrixSlice2::new_with_strides(...)`

. - The
`::repeat(...)`

constructor that is an alternative name to`::from_element(...)`

. `UnitQuaternion::scaled_rotation_between_axis(...)`

and`UnitQuaternion::rotation_between_axis(...)`

that take Unit vectors instead of Vector as arguments.

### Version 0.13§

The **nalgebra-lapack** crate has been updated. This now includes a broad range
matrix decompositions using LAPACK bindings.

This adds support for serialization using the abomonation crate.

#### Breaking semantic change§

- The implementation of slicing with steps now matches the documentation. Before, step identified the number to add to pass from one column/row index to the next one. This made 0 step invalid. Now (and on the documentation so far), the step is the number of ignored row/columns between each row/column. Thus, a step of 0 means that no row/column is ignored. For example, a step of, say, 3 on previous versions should now bet set to 2.

#### Modified§

- The trait
`Axpy`

has been replaced by a metod`.axpy`

. - The alias
`MatrixNM`

is now deprecated. Use`MatrixMN`

instead (we reordered M and N to be in alphabetical order). - In-place componentwise multiplication and division
`.component_mul_mut(...)`

and`.component_div_mut(...)`

have bee deprecated for a future renaming. Use`.component_mul_assign(...)`

and`.component_div_assign(...)`

instead.

#### Added§

`alga::general::Real`

is now re-exported by nalgebra. elements.)`::zeros(...)`

that creates a matrix filled with zeroes.`::from_partial_diagonal(...)`

that creates a matrix from diagonal elements. The matrix can be rectangular. If not enough elements are provided, the rest of the diagonal is set to 0.`.conjugate_transpose()`

computes the transposed conjugate of a complex matrix.`.conjugate_transpose_to(...)`

computes the transposed conjugate of a complex matrix. The result written into a user-provided matrix.`.transpose_to(...)`

is the same as`.transpose()`

but stores the result in the provided matrix.`.conjugate_transpose_to(...)`

is the same as`.conjugate_transpose()`

but stores the result in the provided matrix.- Implements
`IntoIterator`

for`&Matrix`

,`&mut Matrix`

and`Matrix`

. `.mul_to(...)`

multiplies two matrices and stores the result to the given buffer.`.tr_mul_to(...)`

left-multiplies`self.transpose()`

to another matrix and stores the result to the given buffer.`.add_scalar(...)`

that adds a scalar to each component of a matrix.`.add_scalar_mut(...)`

that adds in-place a scalar to each component of a matrix.`.kronecker(a, b)`

computes the kronecker product (i.e. matrix tensor product) of two matrices.`.apply(f)`

replaces each component of a matrix with the results of the closure`f`

called on each of them.

Pure Rust implementation of some Blas operations:

`.iamax()`

retuns the index of the maximum value of a vector.`.axpy(...)`

computes`self = a * x + b * self`

.`.gemv(...)`

computes`self = alpha * a * x + beta * self`

with a matrix and vector`a`

and`x`

.`.ger(...)`

computes`self = alpha * x^t * y + beta * self`

where`x`

and`y`

are vectors.`.gemm(...)`

computes`self = alpha * a * b + beta * self`

where`a`

and`b`

are matrices.`.gemv_symm(...)`

is the same as`.gemv`

except that`self`

is assumed symmetric.`.ger_symm(...)`

is the same as`.ger`

except that`self`

is assumed symmetric.

New slicing methods:

`.rows_range(...)`

that retrieves a reference to a range of rows.`.rows_range_mut(...)`

that retrieves a mutable reference to a range of rows.`.columns_range(...)`

that retrieves a reference to a range of columns.`.columns_range_mut(...)`

that retrieves a mutable reference to a range of columns.

Matrix decompositions implemented in pure Rust:

- Cholesky, SVD, LU, QR, Hessenberg, Schur, Symmetric eigendecompositions, Bidiagonal, Symmetric tridiagonal
- Computation of householder reflectors and givens rotations.

Matrix edition:

`.upper_triangle()`

extracts the upper triangle of a matrix, including the diagonal.`.lower_triangle()`

extracts the lower triangle of a matrix, including the diagonal.`.fill(...)`

fills the matrix with a single value.`.fill_with_identity(...)`

fills the matrix with the identity.`.fill_diagonal(...)`

fills the matrix diagonal with a single value.`.fill_row(...)`

fills a selected matrix row with a single value.`.fill_column(...)`

fills a selected matrix column with a single value.`.set_diagonal(...)`

sets the matrix diagonal.`.set_row(...)`

sets a selected row.`.set_column(...)`

sets a selected column.`.fill_lower_triangle(...)`

fills some sub-diagonals bellow the main diagonal with a value.`.fill_upper_triangle(...)`

fills some sub-diagonals above the main diagonal with a value.`.swap_rows(...)`

swaps two rows.`.swap_columns(...)`

swaps two columns.

Column removal:

`.remove_column(...)`

removes one column.`.remove_fixed_columns<D>(...)`

removes`D`

columns.`.remove_columns(...)`

removes a number of columns known at run-time.

Row removal:

`.remove_row(...)`

removes one row.`.remove_fixed_rows<D>(...)`

removes`D`

rows.`.remove_rows(...)`

removes a number of rows known at run-time.

Column insertion:

`.insert_column(...)`

adds one column at the given position.`.insert_fixed_columns<D>(...)`

adds`D`

columns at the given position.`.insert_columns(...)`

adds at the given position a number of columns known at run-time.

Row insertion:

`.insert_row(...)`

adds one row at the given position.`.insert_fixed_rows<D>(...)`

adds`D`

rows at the given position.`.insert_rows(...)`

adds at the given position a number of rows known at run-time.

Resizing:

`.resize(nrows, ncols, ...)`

resizes`self`

such that it contains`nrows`

rows and`ncols`

columns.`.fixed_resize<R, C>(...)`

resizes`self`

such that it contains`R`

rows and`C`

columns.

### Version 0.12§

The main change of this release is the update of the dependency serde to 1.0.

#### Added§

`.trace()`

that computes the trace of a matrix (the sum of its diagonal elements.)

### Version 0.11§

The website has been fully rewritten and gives a good overview of all the added/modified features.

This version is a major rewrite of the library. Major changes are:

- Algebraic traits are now defined by the alga
crate. All other mathematical traits, except
`Axpy`

have been removed from**nalgebra**. - Methods are now preferred to free functions because they do not require any trait to be used any more.
- Most algebraic entities can be parametrized by type-level integers
to specify their dimensions. Using
`Dynamic`

instead of a type-level integer indicates that the dimension known at run-time only. - Statically-sized
**rectangular**matrices. - More transformation types have been added: unit-sized complex numbers (for
2D rotations), affine/projective/general transformations with
`Affine2/3`

,`Projective2/3`

, and`Transform2/3`

. - Serde serialization is now supported instead of
`rustc_serialize`

. Enable it with the`serde-serialize`

feature. - Matrix
**slices**are now implemented.

#### Added§

Lots of features including rectangular matrices, slices, and Serde serialization. Refer to the brand new website for more details. The following free-functions have been added as well:

`::id()`

that returns the universal identity element of type`Id`

.`::inf_sup()`

that returns both the infimum and supremum of a value at the same time.`::partial_sort2()`

that attempts to sort two values in increasing order.`::wrap()`

that moves a value to the given interval by adding or removing the interval width to it.

#### Modified§

`::cast`

->`::convert`

`point.as_vector()`

->`point.coords`

`na::origin`

->`P::origin()`

`na::is_zero`

->`.is_zero()`

(from num::Zero)`.transform`

->`.transform_point`

/`.transform_vector`

`.translate`

->`.translate_point`

`::dimension::<P>`

->`::dimension::<P::Vector>`

`::angle_between`

->`::angle`

Componentwise multiplication and division has been replaced by methods:

- multiplication ->
`.componentwise_mul`

,`.componentwise_mul_mut`

. - division ->
`.componentwise_div`

,`.componentwise_div_mut`

.

The following free-functions are now replaced by methods (with the same names)
only:
`::cross`

, `::cholesky`

, `::determinant`

, `::diagonal`

, `::eigen_qr`

(becomes
`.eig`

), `::hessenberg`

, `::qr`

, `::to_homogeneous`

, `::to_rotation_matrix`

,
`::transpose`

, `::shape`

.

The following free-functions are now replaced by static methods only:

`::householder_matrix`

under the name`::new_householder_generic`

`::identity`

`::new_identity`

under the name`::identity`

`::from_homogeneous`

`::repeat`

under the name`::from_element`

The following free-function are now replaced methods accessible through traits only:

`::transform`

-> methods`.transform_point`

and`.transform_vector`

of the`alga::linear::Transformation`

trait.`::inverse_transform`

-> methods`.inverse_transform_point`

and`.inverse_transform_vector`

of the`alga::linear::ProjectiveTransformation`

trait.`::translate`

,`::inverse_translate`

,`::rotate`

,`::inverse_rotate`

-> methods from the`alga::linear::Similarity`

trait instead. Those have the same names but end with`_point`

or`_vector`

, e.g.,`.translate_point`

and`.translate_vector`

.`::orthonormal_subspace_basis`

-> method with the same name from`alga::linear::FiniteDimInnerSpace`

.`::canonical_basis_element`

and`::canonical_basis`

-> methods with the same names from`alga::linear::FiniteDimVectorSpace`

.`::rotation_between`

-> method with the same name from the`alga::linear::Rotation`

trait.`::is_zero`

-> method with the same name from`num::Zero`

.

#### Removed§

- The free functions
`::prepend_rotation`

,`::append_rotation`

,`::append_rotation_wrt_center`

,`::append_rotation_wrt_point`

,`::append_transformation`

, and`::append_translation`

have been removed. Instead create the rotation or translation object explicitly and use multiplication to compose it with anything else. - The free function
`::outer`

has been removed. Use column-vector × row-vector multiplication instead. `::approx_eq`

,`::approx_eq_eps`

have been removed. Use the`relative_eq!`

macro from the approx crate instead.`::covariance`

has been removed. There is no replacement for now.`::mean`

has been removed. There is no replacement for now.`::sample_sphere`

has been removed. There is no replacement for now.`::cross_matrix`

has been removed. There is no replacement for now.`::absolute_rotate`

has been removed. There is no replacement for now.`::rotation`

,`::transformation`

,`::translation`

,`::inverse_rotation`

,`::inverse_transformation`

,`::inverse_translation`

have been removed. Use the appropriate methods/field of each transformation type, e.g.,`rotation.angle()`

and`rotation.axis()`

.

### Version 0.10§

#### Added§

Binary operations are now allowed between references as well. For example
`Vector3<f32> + &Vector3<f32>`

is now possible.

#### Modified§

Removed unused parameters to methods from the `ApproxEq`

trait. Those were
required before rust 1.0 to help type inference. The are not needed any more
since it now allowed to write for a type `T`

that implements `ApproxEq`

:
`<T as ApproxEq>::approx_epsilon()`

. This replaces the old form:
`ApproxEq::approx_epsilon(None::<T>)`

.

### Version 0.9§

#### Modified§

Renamed:

`::from_col_vector`

->`::from_column_vector`

`::from_col_iter`

->`::from_column_iter`

`.col_slice`

->`.column_slice`

`.set_col`

->`.set_column`

`::canonical_basis_with_dim`

->`::canonical_basis_with_dimension`

`::from_elem`

->`::from_element`

`DiagMut`

->`DiagonalMut`

`UnitQuaternion::new`

becomes`UnitQuaternion::from_scaled_axis`

or`UnitQuaternion::from_axisangle`

. The new`::new`

method now requires a not-normalized quaternion.

Methods names starting with `new_with_`

now start with `from_`

. This is more
idiomatic in Rust.

The `Norm`

trait now uses an associated type instead of a type parameter.
Other similar trait changes are to be expected in the future, e.g., for the
`Diagonal`

trait.

Methods marked `unsafe`

for reasons unrelated to memory safety are no
longer unsafe. Instead, their name end with `_unchecked`

. In particular:

`Rotation3::new_with_matrix`

->`Rotation3::from_matrix_unchecked`

`PerspectiveMatrix3::new_with_matrix`

->`PerspectiveMatrix3::from_matrix_unchecked`

`OrthographicMatrix3::new_with_matrix`

->`OrthographicMatrix3::from_matrix_unchecked`

#### Added§

- A
`Unit<T>`

type that wraps normalized values. In particular,`UnitQuaternion<N>`

is now an alias for`Unit<Quaternion<N>>`

. `.ln()`

,`.exp()`

and`.powf(..)`

for quaternions and unit quaternions.`::from_parts(...)`

to build a quaternion from its scalar and vector parts.- The
`Norm`

trait now has a`try_normalize()`

that returns`None`

if the norm is too small. - The
`BaseFloat`

and`FloatVector`

traits now inherit from`ApproxEq`

as well. It is clear that performing computations with floats requires approximate equality.

Still WIP: add implementations of abstract algebra traits from the `algebra`

crate for vectors, rotations and points. To enable them, activate the
`abstract_algebra`

feature.

### Version 0.8§

#### Modified§

Almost everything (types, methods, and traits) now use full names instead
of abbreviations (e.g. `Vec3`

becomes `Vector3`

). Most changes are abvious.
Note however that:
- `::sqnorm`

becomes `::norm_squared`

.
- `::sqdist`

becomes `::distance_squared`

.
- `::abs`

, `::min`

, etc. did not change as this is a common name for
absolute values on, e.g., the libc.
- Dynamically sized structures keep the `D`

prefix, e.g., `DMat`

becomes
`DMatrix`

.

All files with abbreviated names have been renamed to their full version,
e.g., `vec.rs`

becomes `vector.rs`

.

### Version 0.7§

#### Added§

- Added implementation of assignement operators (+=, -=, etc.) for everything.

#### Modified§

- Points and vectors are now linked to each other with associated types (on the PointAsVector trait).

### Version 0.6§

**Announcement:** a users forum has been created for `nalgebra`

, `ncollide`

, and `nphysics`

. See
you there!

#### Added§

- Added a dependency to generic-array. Feature-gated:
requires
`features="generic_sizes"`

. - Added statically sized vectors with user-defined sizes:
`VectorN`

. Feature-gated: requires`features="generic_sizes"`

. - Added similarity transformations (an uniform scale followed by a rotation followed by a
translation):
`Similarity2`

,`Similarity3`

.

#### Removed§

- Removed zero-sized elements
`Vector0`

,`Point0`

. - Removed 4-dimensional transformations
`Rotation4`

and`Isometry4`

(which had an implementation to incomplete to be useful).

#### Modified§

- Vectors are now multipliable with isometries. This will result into a pure rotation (this is how vectors differ from point semantically: they design directions so they are not translatable).
`{Isometry3, Rotation3}::look_at`

reimplemented and renamed to`::look_at_rh`

and`::look_at_lh`

to agree with the computer graphics community (in particular, the GLM library). Use the`::look_at_rh`

variant to build a view matrix that may be successfully used with`Persp`

and`Ortho`

.- The old
`{Isometry3, Rotation3}::look_at`

implementations are now called`::new_observer_frame`

. - Rename every
`fov`

on`Persp`

to`fovy`

. - Fixed the perspective and orthographic projection matrices.