Padovan n-step number sequences: Difference between revisions
m
→Python: Functional
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<lang python>'''Padovan N-step series'''
from itertools import islice, repeat
# padovans :: Int -> [Int]
def padovans(n):
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def recurrence(ns):
return ns[0], ns[1:] + [sum(take(n)(ns))]
return unfoldr(recurrence)(
take(1 + n)(
repeat(1) if 3 > n else padovans(n - 1)
)
) if 0 <= n else []
# ------------------------- TEST -------------------------
# main :: IO ()
def main():
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def sample(n):
return take(15)(padovans(n))
def columnWidth(n):
def go(xs):
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])
return go
print(
fTable('Padovan n-step series:')(repr)(
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)(sample)(range(2, 1 + 8))
)
# ----------------------- GENERIC ------------------------
# unfoldr :: (b -> Maybe (a, b)) -> b -> [a]
def unfoldr(f):
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valueResidue = f(valueResidue[1])
return go
# take :: Int -> [a] -> [a]
# take :: Int -> String -> String
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)
return go
# ---------------------- FORMATTING ----------------------
# fTable :: String -> (a -> String) ->
# (b -> String) -> (a -> b) -> [a] -> String
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ys = [xShow(x) for x in xs]
w = max(map(len, ys))
def arrowed(x, y):
return y.rjust(w, ' ') + ' ->' + (
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return gofx
return gox
# MAIN ---
if __name__ == '__main__':
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