Copyright | (c) Amy de Buitléir 2012-2015 |
---|---|

License | BSD-style |

Maintainer | amy@nualeargais.ie |

Stability | experimental |

Portability | portable |

Safe Haskell | Safe |

Language | Haskell98 |

Tools for identifying patterns in data.

- adjustNum :: (Num a, Ord a, Eq a) => a -> a -> a -> a
- absDifference :: Num a => a -> a -> a
- adjustVector :: (Num a, Ord a, Eq a) => [a] -> a -> [a] -> [a]
- adjustVectorPreserveLength :: (Num a, Ord a, Eq a) => [a] -> a -> [a] -> [a]
- euclideanDistanceSquared :: Num a => [a] -> [a] -> a
- magnitudeSquared :: Num a => [a] -> a
- data NormalisedVector a
- normalise :: Floating a => [a] -> NormalisedVector a
- data ScaledVector a
- scale :: Fractional a => [(a, a)] -> [a] -> ScaledVector a
- scaleAll :: (Fractional a, Ord a) => [[a]] -> [ScaledVector a]

# Numbers as patterns

absDifference :: Num a => a -> a -> a Source

# Numeric vectors as patterns

## Raw vectors

adjustVector :: (Num a, Ord a, Eq a) => [a] -> a -> [a] -> [a] Source

adjusts each element of
`adjustVector`

target amount vector`vector`

to move it closer to the corresponding element of
`target`

.
The amount of adjustment is controlled by the learning rate
`amount`

, which is a number between 0 and 1.
Larger values of `amount`

permit more adjustment.
If `amount`

=1, the result will be identical to the `target`

.
If `amount`

=0, the result will be the unmodified `pattern`

.
If `target`

is shorter than `vector`

, the result will be the same
length as `target`

.
If `target`

is longer than `vector`

, the result will be the same
length as `vector`

.

adjustVectorPreserveLength :: (Num a, Ord a, Eq a) => [a] -> a -> [a] -> [a] Source

Same as

, except that the result will always be
the same length as `adjustVector`

`vector`

.
This means that if `target`

is shorter than `vector`

, the
"leftover" elements of `vector`

will be copied the result,
unmodified.

euclideanDistanceSquared :: Num a => [a] -> [a] -> a Source

Calculates the square of the Euclidean distance between two vectors.

magnitudeSquared :: Num a => [a] -> a Source

## Normalised vectors

data NormalisedVector a Source

A vector that has been normalised, i.e., the magnitude of the vector = 1.

Show a => Show (NormalisedVector a) Source |

normalise :: Floating a => [a] -> NormalisedVector a Source

Normalises a vector

## Scaled vectors

data ScaledVector a Source

A vector that has been scaled so that all elements in the vector
are between zero and one. To scale a set of vectors, use

. Alternatively, if you can identify a maximum and
minimum value for each element in a vector, you can scale
individual vectors using `scaleAll`

.`scale`

Show a => Show (ScaledVector a) Source |

scale :: Fractional a => [(a, a)] -> [a] -> ScaledVector a Source

Given a vector `qs`

of pairs of numbers, where each pair represents
the maximum and minimum value to be expected at each index in
`xs`

,

scales the vector `scale`

qs xs`xs`

element by element,
mapping the maximum value expected at that index to one, and the
minimum value to zero.

scaleAll :: (Fractional a, Ord a) => [[a]] -> [ScaledVector a] Source

Scales a set of vectors by determining the maximum and minimum values at each index in the vector, and mapping the maximum value to one, and the minimum value to zero.