RosettaCodeData/Task/Functional-coverage-tree/Python/functional-coverage-tree-3.py

464 lines
13 KiB
Python

'''Functional coverage tree'''
from itertools import chain, product
from functools import reduce
# main :: IO ()
def main():
'''Tabular outline serialisation of a parse tree
decorated with computations of:
1. Weighted coverage of each tree node.
2. Each node's share of the total project's
remaining work.
'''
columnWidths = [31, 9, 9, 9]
delimiter = '|'
reportLines = REPORT.splitlines()
columnTitles = init(columnNames(delimiter)(reportLines[0]))
# ------ SERIALISATION OF DECORATED PARSE TREE -------
print(titleLine(delimiter)(columnWidths)(
columnTitles + ['share of residue']
))
print(indentedLinesFromTree(' ', tabulation(columnWidths))(
# -------- TWO COMPUTATIONS BY TRAVERSAL ---------
withResidueShares(1.0)(
foldTree(weightedCoverage)(
# --- TREE FROM PARSE OF OUTLINE TEXT ----
fmapTree(
recordFromKeysDefaultsDelimiterAndLine(
columnTitles
)(
[str, float, float])([
'?', 1.0, 0.0
])(delimiter)
)(
forestFromIndentLevels(
indentLevelsFromLines(
reportLines[1:]
)
)[0]
)
)
)
))
# ---- WEIGHTED COVERAGE, AND SHARE OF TOTAL RESIDUE -----
# weightedCoverage :: Tree Dict ->
# [Tree Dict] -> Tree Dict
def weightedCoverage(x):
'''The weighted coverage of a tree node,
as a function of the weighted averages
of its children.
'''
def go(xs):
cws = [
(r['coverage'], r['weight']) for r
in [root(x) for x in xs]
]
totalWeight = reduce(lambda a, x: a + x[1], cws, 0)
return Node(dict(
x, **{
'coverage': round(reduce(
lambda a, cw: a + (cw[0] * cw[1]),
cws, x['coverage']
) / (totalWeight if 0 < totalWeight else 1), 5)
}
))(xs)
return go
# withResidueShares :: Float -> Tree Dict -> Tree Dict
def withResidueShares(shareOfTotal):
'''A Tree of dictionaries additionally decorated with each
node's proportion of the total project's outstanding work.
'''
def go(fraction, node):
[nodeRoot, nodeNest] = ap([root, nest])([node])
weights = [root(x)['weight'] for x in nodeNest]
siblingsTotal = sum(weights)
return Node(
insertDict('residual_share')(
round(fraction * (1 - nodeRoot['coverage']), 5)
)(nodeRoot)
)(
map(
go,
[fraction * (w / siblingsTotal) for w in weights],
nodeNest
)
)
return lambda tree: go(shareOfTotal, tree)
# ------------------ OUTLINE TABULATION ------------------
# tabulation :: [Int] -> String -> Dict -> String
def tabulation(columnWidths):
'''Indented string representation of a node
in a functional coverage tree.
'''
return lambda indent, dct: '| '.join(map(
lambda k, w: (
(indent if 10 < w else '') + str(dct.get(k, ''))
).ljust(w, ' '),
dct.keys(),
columnWidths
))
# titleLine :: String -> [Int] -> [String] -> String
def titleLine(delimiter):
'''A string consisting of a spaced and delimited
series of upper-case column titles.
'''
return lambda columnWidths: lambda ks: (
delimiter + ' '
).join(map(
lambda k, w: k.ljust(w, ' '),
[k.upper() for k in ks],
columnWidths
))
# ------------ GENERIC AND REUSABLE FUNCTIONS ------------
# Node :: a -> [Tree a] -> Tree a
def Node(v):
'''Constructor for a Tree node which connects a
value of some kind to a list of zero or
more child trees.
'''
return lambda xs: {'type': 'Tree', 'root': v, 'nest': xs}
# ap (<*>) :: [(a -> b)] -> [a] -> [b]
def ap(fs):
'''The application of each of a list of functions,
to each of a list of values.
'''
def go(xs):
return [
f(x) for (f, x)
in product(fs, xs)
]
return go
# columnNames :: String -> String -> [String]
def columnNames(delimiter):
'''A list of lower-case keys derived from
a header line and a delimiter character.
'''
return compose(
fmapList(compose(toLower, strip)),
splitOn(delimiter)
)
# compose :: ((a -> a), ...) -> (a -> a)
def compose(*fs):
'''Composition, from right to left,
of a series of functions.
'''
return lambda x: reduce(
lambda a, f: f(a),
fs[::-1], x
)
# concatMap :: (a -> [b]) -> [a] -> [b]
def concatMap(f):
'''A concatenated list over which a function has been mapped.
The list monad can be derived by using a function f which
wraps its output in a list,
(using an empty list to represent computational failure).
'''
def go(xs):
return chain.from_iterable(map(f, xs))
return go
# div :: Int -> Int -> Int
def div(x):
'''Integer division.'''
return lambda y: x // y
# first :: (a -> b) -> ((a, c) -> (b, c))
def first(f):
'''A simple function lifted to a function over a tuple,
with f applied only the first of two values.
'''
return lambda xy: (f(xy[0]), xy[1])
# flip :: (a -> b -> c) -> b -> a -> c
def flip(f):
'''The (curried or uncurried) function f with its
arguments reversed.
'''
return lambda a: lambda b: f(b)(a)
# fmapList :: (a -> b) -> [a] -> [b]
def fmapList(f):
'''fmap over a list.
f lifted to a function over a list.
'''
return lambda xs: [f(x) for x in xs]
# fmapTree :: (a -> b) -> Tree a -> Tree b
def fmapTree(f):
'''A new tree holding the results of
an application of f to each root in
the existing tree.
'''
def go(x):
return Node(
f(x['root'])
)([go(v) for v in x['nest']])
return go
# foldTree :: (a -> [b] -> b) -> Tree a -> b
def foldTree(f):
'''The catamorphism on trees. A summary
value defined by a depth-first fold.
'''
def go(node):
return f(root(node))([
go(x) for x in nest(node)
])
return go
# forestFromIndentLevels :: [(Int, a)] -> [Tree a]
def forestFromIndentLevels(tuples):
'''A list of trees derived from a list of values paired
with integers giving their levels of indentation.
'''
def go(xs):
if xs:
intIndent, v = xs[0]
firstTreeLines, rest = span(
lambda x: intIndent < x[0]
)(xs[1:])
return [Node(v)(go(firstTreeLines))] + go(rest)
else:
return []
return go(tuples)
# fst :: (a, b) -> a
def fst(tpl):
'''First member of a pair.'''
return tpl[0]
# indentLevelsFromLines :: [String] -> [(Int, String)]
def indentLevelsFromLines(xs):
'''Each input line stripped of leading
white space, and tupled with a preceding integer
giving its level of indentation from 0 upwards.
'''
indentTextPairs = list(map(
compose(first(len), span(isSpace)),
xs
))
indentUnit = min(concatMap(
lambda x: [x[0]] if x[0] else []
)(indentTextPairs))
return list(map(
first(flip(div)(indentUnit)),
indentTextPairs
))
# indentedLinesFromTree :: String -> (String -> a -> String) ->
# [Tree a] -> String
def indentedLinesFromTree(strTab, f):
'''An indented line rendering of a tree, in which
the function f stringifies a root value.
'''
def go(indent):
return lambda node: [f(indent, node['root'])] + list(
concatMap(
go(strTab + indent)
)(node['nest'])
)
return lambda tree: '\n'.join(go('')(tree))
# init :: [a] -> [a]
def init(xs):
'''A list containing all the elements
of xs except the last.
'''
return xs[:-1]
# insertDict :: String -> a -> Dict -> Dict
def insertDict(k):
'''A new dictionary updated with a (k, v) pair.'''
def go(v, dct):
return dict(dct, **{k: v})
return lambda v: lambda dct: go(v, dct)
# isSpace :: Char -> Bool
# isSpace :: String -> Bool
def isSpace(s):
'''True if s is not empty, and
contains only white space.
'''
return s.isspace()
# lt (<) :: Ord a => a -> a -> Bool
def lt(x):
'''True if x < y.'''
return lambda y: (x < y)
# nest :: Tree a -> [Tree a]
def nest(t):
'''Accessor function for children of tree node.'''
return t['nest'] if 'nest' in t else None
# recordFromKeysDefaultsAndLine :: String ->
# { name :: String, weight :: Float, completion :: Float }
def recordFromKeysDefaultsDelimiterAndLine(columnTitles):
'''A dictionary of key-value pairs, derived from a
delimited string, together with ordered lists of
key-names, types, default values, and a delimiter.
'''
return lambda ts: lambda vs: lambda delim: lambda s: dict(
map(
lambda k, t, v, x: (k, t(x) if x else v),
columnTitles, ts, vs,
map(strip, splitOn(delim)(s))
)
)
# root :: Tree a -> a
def root(t):
'''Accessor function for data of tree node.'''
return t['root'] if 'root' in t else None
# strip :: String -> String
def strip(s):
'''A copy of s without any leading or trailling
white space.
'''
return s.strip()
# span :: (a -> Bool) -> [a] -> ([a], [a])
def span(p):
'''The longest (possibly empty) prefix of xs
that contains only elements satisfying p,
tupled with the remainder of xs.
span p xs is equivalent to (takeWhile p xs, dropWhile p xs).
'''
def match(ab):
b = ab[1]
return not b or not p(b[0])
def f(ab):
a, b = ab
return a + [b[0]], b[1:]
def go(xs):
return until(match)(f)(([], xs))
return go
# splitOn :: String -> String -> [String]
def splitOn(pat):
'''A list of the strings delimited by
instances of a given pattern in s.
'''
return lambda xs: (
xs.split(pat) if isinstance(xs, str) else None
)
# toLower :: String -> String
def toLower(s):
'''String in lower case.'''
return s.lower()
# until :: (a -> Bool) -> (a -> a) -> a -> a
def until(p):
'''The result of repeatedly applying f until p holds.
The initial seed value is x.
'''
def go(f):
def g(x):
v = x
while not p(v):
v = f(v)
return v
return g
return go
# MAIN ----------------------------------------------------
if __name__ == '__main__':
REPORT = '''NAME_HIERARCHY |WEIGHT |COVERAGE |
cleaning | | |
house1 |40 | |
bedrooms | |0.25 |
bathrooms | | |
bathroom1 | |0.5 |
bathroom2 | | |
outside_lavatory | |1 |
attic | |0.75 |
kitchen | |0.1 |
living_rooms | | |
lounge | | |
dining_room | | |
conservatory | | |
playroom | |1 |
basement | | |
garage | | |
garden | |0.8 |
house2 |60 | |
upstairs | | |
bedrooms | | |
suite_1 | | |
suite_2 | | |
bedroom_3 | | |
bedroom_4 | | |
bathroom | | |
toilet | | |
attics | |0.6 |
groundfloor | | |
kitchen | | |
living_rooms | | |
lounge | | |
dining_room | | |
conservatory | | |
playroom | | |
wet_room_&_toilet | | |
garage | | |
garden | |0.9 |
hot_tub_suite | |1 |
basement | | |
cellars | |1 |
wine_cellar | |1 |
cinema | |0.75 |'''
main()