generate_n_random_sum_fixed.py

# https://stackoverflow.com/questions/21782329/generate-n-random-numbers-whose-sum-is-a-constant-k-excel
# https://stackoverflow.com/questions/7289136/how-to-make-5-random-numbers-with-sum-of-100
# https://stackoverflow.com/questions/18659858/generating-a-list-of-random-numbers-summing-to-1
# can i call this - Dirichlet distribution like ?
from random import random 
from random import randint

def gen(l,h):
	return round( l + random() * (h-l) )

def fn_duration(total_clip_time, shorten_clip_time, n):
  cut_point = []
  clip_point = []
  low = 0
  r = total_clip_time/n

  # find points
  for i in range(n-1):
    high = int( shorten_clip_time/2 )
    temp = randint(low,high)
    shorten_clip_time -= temp
    cut_point.append(temp)
  cut_point.append(shorten_clip_time)

  # make 
  if max(cut_point) <= r/2:
    clip_point = [randint(r*x, int(r*(2*x+1)/2)) for x in range(n)]
  else:
    print("not possible to cut")

  result = [ [ clip_point[i], clip_point[i] + cut_point[i] ] for i in range(n) ]  
  return result

how_many = 20
limit = 180
total = 18000
fn_duration(total, limit, how_many)