algorithm-notes/src/python/utils/utils.py at main · lfir/algorithm-notes · GitHub

Repository navigation

History

64 lines (51 loc) · 1.81 KB

Raw

from random import randrange

from time import gmtime, process_time, strftime

def randstr(charlist, length):

"""Generates a string with characters chosen at random from the string

received as first argument. If an empty string is received, lower

and upper case letters and decimal digits are used by default.

Positional arguments:

charlist -- Characters than can appear in the result.

length -- Desidred length of the resulting string.

"""

res = ""

chars = ""

if not charlist:

chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"

else:

chars = charlist

l = len(chars)

for _ in range(length):

nextchar = randrange(l)

res = res + chars[nextchar]

return res

def show_process_time(original_function):

"""Decorator that prints the process time elapsed during the execution

of the function decorated, up to seconds precision.

https://docs.python.org/dev/library/time.html#time.process_time

"""

def timed_function(*args, **kwargs):

start = process_time()

res = original_function(*args, **kwargs)

end = process_time()

print(strftime("CPU time elapsed: %H:%M:%S", gmtime(end - start)))

return res

return timed_function

def subsequences(sequence):

"""Returns a generator of all the sub-sequences of target sequence,

that preserve the order of the elements. Each sub-sequence is represented

as a tuple.

Example:

for i, e in enumerate(subsequences([1, 2])):

print(i, e)

--> 0 ()

--> 1 (1,)

--> 2 (1, 2)

--> 3 (2,)

"""

elems = len(sequence)

yield ()

for startidx in range(elems):

for endidx in range(startidx, elems):

subsequence = tuple(sequence[startidx : endidx + 1])

yield subsequence

algorithm-notes/src/python/utils/utils.py at main · lfir/algorithm-notes · GitHub

Repository navigation

Expand file tree

Breadcrumbs

utils.py

Latest commit

History

Breadcrumbs

utils.py

File metadata and controls