TaskVine Functional Examples

These three examples show the use of higher order functions map, pair and treereduce which transparently apply Python functions to data via remote tasks:

#!/usr/bin/env python

# Example program to show use of map() abstraction
# which generates PythonTasks automatically.

import ndcctools.taskvine as vine
import sys

def calc_age(birth_year):
    import datetime
    current_year = datetime.date.today().year
    return current_year - birth_year

birth_years = [
        2017,2019,2015,2018,2020,
        2005,2008,2006,2004,2007,
        1999,2002,2000,1997,1995,
        1990,1989,1993,1987,1988,
        1980,1975,1978,1983,1977,
]

if __name__ == "__main__":
    m = vine.Manager()
    print(f"listening on port {m.port}")

    print("mapping ages...")
    ages = m.map(calc_age, birth_years)

    for (birth_year, age) in zip (birth_years, ages):
        print(f"{birth_year}: {age}")
# vim: set sts=4 sw=4 ts=4 expandtab ft=python:

# This example program shows the use of the pair()
# abstraction to generate all pairs of several values.

import ndcctools.taskvine as vine
import sys

def make_name(namepair):
    return namepair[0] + " " + namepair[1]

firsts = ["Joe", "Sarah", "Mark", "Lewis", "Jane", "James", "Abby", "Kate",
        "Sean", "William", "Emma", "Miles", "Grace", "Cole", "Robert"]

lasts = ["Smith", "Johnson", "Thomas", "Long", "Jackson", "Knoddington",
        "Riley", "Shirley", "Donaldson", "Madden", "Tyler", "Morales",
        "McKinsey", "Perez", "Redford"]

if __name__ == "__main__":
    m = vine.Manager()
    print("listening on port", m.port)

    print("pairing first and last names...")
    result = m.pair(make_name, firsts, lasts, chunksize=3)

    try:
        print("\n".join(result))
    except:
        # some error in execution...
        pass

# vim: set sts=4 sw=4 ts=4 expandtab ft=python:

#!/usr/bin/env python3

import ndcctools.taskvine as vine
import sys

def find_max(nums):
    return max(nums)

numbers = [1,10,10000,100,1000,
        57,90,68,72,45,
        4268,643,985,6543,
        7854,2365,98765,123,
        12,34,56,78,90]

if __name__ == "__main__":
    m = vine.Manager()
    print("listening on port", m.port)

    print("reducing array...")
    max_number = m.tree_reduce(find_max, numbers, chunksize=3)

    print(f"maximum number is {max_number}")

# vim: set sts=4 sw=4 ts=4 expandtab ft=python: