RosettaCodeData/Task/Sparkline-in-unicode/Python/sparkline-in-unicode-2.py

171 lines
3.9 KiB
Python

'''Sparkline in Unicode'''
from functools import reduce
import operator
import re
# ------------------- LABELLED SPARKLINE -------------------
# sparkLine :: [Float] -> [String]
def sparkLine(xs):
'''Unicode sparkline summary of a
list of floating point numbers.
'''
def go(xs):
ys = sorted(xs)
mn, mx = ys[0], ys[-1]
n = len(xs)
mid = n // 2
w = (mx - mn) / 8
lbounds = list(map(lambda i: mn + (w * i), range(1, 8)))
le = curry(operator.le)
# spark :: Float -> Char
def spark(x):
def go(i):
return '▁▂▃▄▅▆▇'[i]
return maybe('')(go)(
findIndex(le(x))(lbounds)
)
return [
''.join(map(spark, xs)),
' '.join(map(str, xs)),
'\t'.join([
'Min ' + str(mn),
'Mean ' + str(round(mean(xs), 2)),
'Median ' + str(
(ys[mid - 1] + ys[mid]) / 2 if even(n) else (
ys[mid]
)
),
'Max ' + str(mx)
]),
''
]
return go(xs) if xs else []
# -------------------------- TEST --------------------------
# main :: IO ()
def main():
'''Tested on some sample lists.
'''
print(
unlines(map(
compose(compose(unlines, sparkLine), readFloats),
[
"0, 1, 19, 20",
"0, 999, 4000, 4999, 7000, 7999",
"1 2 3 4 5 6 7 8 7 6 5 4 3 2 1",
"1.5, 0.5 3.5, 2.5 5.5, 4.5 7.5, 6.5"
]
))
)
# ------------------------ GENERIC -------------------------
# Just :: a -> Maybe a
def Just(x):
'''Constructor for an inhabited Maybe (option type) value.
Wrapper containing the result of a computation.
'''
return {'type': 'Maybe', 'Nothing': False, 'Just': x}
# Nothing :: Maybe a
def Nothing():
'''Constructor for an empty Maybe (option type) value.
Empty wrapper returned where a computation is not possible.
'''
return {'type': 'Maybe', 'Nothing': True}
# compose :: ((a -> a), ...) -> (a -> a)
def compose(*fs):
'''Composition, from right to left,
of a series of functions.
'''
def go(f, g):
def fg(x):
return f(g(x))
return fg
return reduce(go, fs, lambda x: x)
# curry :: ((a, b) -> c) -> a -> b -> c
def curry(f):
'''A curried function derived
from an uncurried function.
'''
return lambda x: lambda y: f(x, y)
# even :: Int -> Bool
def even(x):
'''True if x is an integer
multiple of two.
'''
return 0 == x % 2
# findIndex :: (a -> Bool) -> [a] -> Maybe Int
def findIndex(p):
'''Just the first index at which an
element in xs matches p,
or Nothing if no elements match.
'''
def go(xs):
try:
return Just(next(
i for i, v in enumerate(xs) if p(v)
))
except StopIteration:
return Nothing()
return go
# maybe :: b -> (a -> b) -> Maybe a -> b
def maybe(v):
'''Either the default value v, if m is Nothing,
or the application of f to x,
where m is Just(x).
'''
return lambda f: lambda m: v if (
None is m or m.get('Nothing')
) else f(m.get('Just'))
# mean :: [Num] -> Float
def mean(xs):
'''The arithmetic mean of the numeric
values in xs.
'''
return sum(xs) / float(len(xs))
# readFloats :: String -> [Float]
def readFloats(s):
'''A list of floats parsed from
a numeric string delimited by
commas and/or white space.
'''
return list(map(
float,
re.split(r'[\s,]+', s)
))
# unlines :: [String] -> String
def unlines(xs):
'''A single string formed by the intercalation
of a list of strings with the newline character.
'''
return '\n'.join(xs)
# MAIN ---
if __name__ == '__main__':
main()