Stability | experimental |
---|---|

Maintainer | Alberto Ruiz <aruiz@um.es> |

Tensor computations. Indices can only be contracted if they are of different `Variant`

type.

- type Tensor t = NArray Variant t
- data Variant
- listTensor :: Coord t => [Int] -> [t] -> Tensor t
- superindex :: Coord t => Name -> [Tensor t] -> Tensor t
- subindex :: Coord t => Name -> [Tensor t] -> Tensor t
- vector :: [Double] -> Tensor Double
- covector :: [Double] -> Tensor Double
- transf :: [[Double]] -> Tensor Double
- switch :: Tensor t -> Tensor t
- cov :: NArray i t -> Tensor t
- contrav :: NArray i t -> Tensor t
- forget :: NArray i t -> Array t
- module Numeric.LinearAlgebra.Array

# The Tensor type

Creates a tensor from a list of dimensions and a list of coordinates. A positive dimension means that the index is assumed to be contravariant (vector-like), and a negative dimension means that the index is assumed to be covariant (like a linear function, or covector). Contractions can only be performed between indices of different type.

# Tensor creation utilities

vector :: [Double] -> Tensor DoubleSource

Create a contravariant 1st order tensor from a list of coordinates.

covector :: [Double] -> Tensor DoubleSource

Create a covariant 1st order tensor from a list of coordinates.

transf :: [[Double]] -> Tensor DoubleSource

Create a 1-contravariant, 1-covariant 2nd order from list of lists of coordinates.

# Index manipulation

switch :: Tensor t -> Tensor tSource

Change the `Variant`

nature of all dimensions to the opposite ones.

# General array operations

module Numeric.LinearAlgebra.Array