 | NumericPrelude-0.0: An experimental alternative hierarchy of numeric type classes | Contents | Index |
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| MathObj.PartialFraction | | Portability | portable | | Stability | provisional | | Maintainer | numericprelude@henning-thielemann.de |
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| Description |
Implementation of partial fractions.
Useful e.g. for fractions of integers and fractions of polynomials.
For the considered ring the prime factorization must be unique.
- **
What about negative primes in denominator factors?
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| Synopsis |
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| data T a = Cons a (Map (ToOrd a) [a]) | | | fromFractionSum :: C a => a -> [(a, [a])] -> T a | | | toFractionSum :: C a => T a -> (a, [(a, [a])]) | | | appPrec :: Int | | | toFraction :: C a => T a -> T a | | | toFactoredFraction :: C a => T a -> ([a], a) | | | multiToFraction :: C a => a -> [a] -> T a | | | hornerRev :: C a => a -> [a] -> a | | | fromFactoredFraction :: (C a, C a) => [a] -> a -> T a | | | fromFactoredFractionAlt :: (C a, C a) => [a] -> a -> T a | | | multiFromFraction :: C a => [a] -> a -> (a, [a]) | | | fromValue :: a -> T a | | | reduceHeads :: C a => T a -> T a | | | carryRipple :: C a => a -> [a] -> (a, [a]) | | | normalizeModulo :: C a => T a -> T a | | | removeZeros :: (C a, C a) => T a -> T a | | | zipWith :: C a => (a -> a -> a) -> ([a] -> [a] -> [a]) -> T a -> T a -> T a | | | mulFrac :: C a => T a -> T a -> (a, a) | | | mulFrac' :: C a => T a -> T a -> (T a, T a) | | | mulFracStupid :: C a => T a -> T a -> ((T a, T a), T a) | | | mulFracOverlap :: C a => T a -> T a -> ((T a, T a), T a) | | | scaleFrac :: (C a, C a) => T a -> T a -> T a | | | scaleInt :: (C a, C a) => a -> T a -> T a | | | mul :: (C a, C a) => T a -> T a -> T a | | | mulFast :: (C a, C a) => T a -> T a -> T a | | | indexMapMapWithKey :: (a -> b -> c) -> Map (ToOrd a) b -> Map (ToOrd a) c | | | indexMapToList :: Map (ToOrd a) b -> [(a, b)] | | | indexMapFromList :: C a => [(a, b)] -> Map (ToOrd a) b | | | mapApplySplit :: Ord a => a -> (c -> c -> c) -> (b -> c) -> (Map a b -> Map a c) -> Map a b -> Map a c |
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| Documentation |
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| data T a |
| Cons z (indexMapFromList [(x0,[y00,y01]), (x1,[y10]), (x2,[y20,y21,y22])])
represents the partial fraction
z + y00x0 + y01x0^2 + y10x1 + y20x2 + y21x2^2 + y22x2^3
The denominators x0, x1, x2, ... must be irreducible,
but we can't check this in general.
It is also not enough to have relatively prime denominators,
because when adding two partial fraction representations
there might concur denominators that have non-trivial common divisors.
| | Constructors | |  Instances | |
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| fromFractionSum :: C a => a -> [(a, [a])] -> T a |
| Unchecked construction.
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| toFractionSum :: C a => T a -> (a, [(a, [a])]) |
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| appPrec :: Int |
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| toFraction :: C a => T a -> T a |
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| toFactoredFraction :: C a => T a -> ([a], a) |
| C is not really necessary here and
only due to invokation of toFraction.
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| multiToFraction :: C a => a -> [a] -> T a |
| C is not really necessary here and
only due to invokation of %.
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| hornerRev :: C a => a -> [a] -> a |
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| fromFactoredFraction :: (C a, C a) => [a] -> a -> T a |
fromFactoredFraction x y
computes the partial fraction representation of y % product x,
where the elements of x must be irreducible.
There are more direct methods for special cases
like polynomials over rational numbers
where the denominators are linear factors.
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| fromFactoredFractionAlt :: (C a, C a) => [a] -> a -> T a |
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| multiFromFraction :: C a => [a] -> a -> (a, [a]) |
| The list of denominators must contain equal elements.
Sorry for this hack.
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| fromValue :: a -> T a |
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| reduceHeads :: C a => T a -> T a |
| A normalization step which separates the integer part
from the leading fraction of each sub-list.
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| carryRipple :: C a => a -> [a] -> (a, [a]) |
| Cf. Number.Positional
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| normalizeModulo :: C a => T a -> T a |
| A normalization step which reduces all elements in sub-lists
modulo their denominators.
Zeros might be the result, that must be remove with removeZeros.
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| removeZeros :: (C a, C a) => T a -> T a |
| Remove trailing zeros in sub-lists
because if lists are converted to fractions by multiToFraction
we must be sure that the denominator of the (cancelled) fraction
is indeed the stored power of the irreducible denominator.
Otherwise mulFrac leads to wrong results.
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| zipWith :: C a => (a -> a -> a) -> ([a] -> [a] -> [a]) -> T a -> T a -> T a |
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| mulFrac :: C a => T a -> T a -> (a, a) |
Transforms a product of two partial fractions
into a sum of two fractions.
The denominators must be at least relatively prime.
Since T requires irreducible denominators,
these are also relatively prime.
Example: mulFrac (1%6) (1%4) fails because of the common divisor 2.
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| mulFrac' :: C a => T a -> T a -> (T a, T a) |
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| mulFracStupid :: C a => T a -> T a -> ((T a, T a), T a) |
| Works always but simply puts the product into the last fraction.
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| mulFracOverlap :: C a => T a -> T a -> ((T a, T a), T a) |
| Also works if the operands share a non-trivial divisor.
However the results are quite arbitrary.
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| scaleFrac :: (C a, C a) => T a -> T a -> T a |
| Expects an irreducible denominator as associate in standard form.
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| scaleInt :: (C a, C a) => a -> T a -> T a |
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| mul :: (C a, C a) => T a -> T a -> T a |
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| mulFast :: (C a, C a) => T a -> T a -> T a |
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| Helper functions for work with Maps with Indexable keys
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| indexMapMapWithKey :: (a -> b -> c) -> Map (ToOrd a) b -> Map (ToOrd a) c |
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| indexMapToList :: Map (ToOrd a) b -> [(a, b)] |
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| indexMapFromList :: C a => [(a, b)] -> Map (ToOrd a) b |
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| mapApplySplit :: Ord a => a -> (c -> c -> c) -> (b -> c) -> (Map a b -> Map a c) -> Map a b -> Map a c |
| Apply a function on a specific element if it exists,
and another function to the rest of the map.
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| Produced by Haddock version 0.7 |