How to generate a list of numbers in python

Question

guys. I am now working on a python algorithm and I am new to python. I'd like to generate a list of numbers like 4, 7, 8, 11, 12, 13, 16, 17, 18, 19, 22, 23, 24, 25... with 2 for loops.

I've done some work to find some numbers and I am close to the result I want, which is generate a list contains this numbers

My code is here:

for x in range(0, 6, 1):
        start_ind = int(((x+3) * (x+2)) / 2 + 1)
        print("start index is ", [start_ind], x)
        start_node = node[start_ind]
        for y in range(0, x):
            ind = start_ind + y + 1
            ind_list = node[ind]
            index = [ind_list]
            print(index)

Node is a list:

node = ['n%d' % i for i in range(0, 36, 1)]

What I received from this code is:

start index is  [7] 1
['n8']
start index is  [11] 2
['n12']
['n13']
start index is  [16] 3
['n17']
['n18']
['n19']
start index is  [22] 4
['n23']
['n24']
['n25']
['n26']
start index is  [29] 5
['n30']
['n31']
['n32']
['n33']
['n34']

Do you want a list of numbers like that list or do you want exactly that list of numbers? Do you know if can be generated by some algorithm or is it an arbitrary random list? — JeffUK
– JeffUK, Commented Dec 6, 2020 at 14:31
@JeffUK Jeff, what I want is a list with exact numbers. It would be [4, 7, 8, 11, 12......] — LeYoung Chen
– LeYoung Chen, Commented Dec 6, 2020 at 14:35
@JeffUK My code could print them like the above, but I can't put them into a list. — LeYoung Chen
– LeYoung Chen, Commented Dec 6, 2020 at 14:46
So you're saying your algorithm works, you just need to know how to append these numbers to a list instead of printing them sequentially? — JeffUK
– JeffUK, Commented Dec 6, 2020 at 14:48

JeffUK · Accepted Answer · 2020-12-06 14:50:59Z

1

This seems to give the same list: and I think it's much clearer what's happening!

val=4
result=[]
for i in range(1,7):
    for j in range(val,val+i):
       val = val+1
       result.append(j)
    val = j+3

print(result)

answered Dec 6, 2020 at 14:50

JeffUK

4,2912 gold badges22 silver badges35 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

LeYoung Chen Over a year ago

It works to find what I want. Thank for your help!

piterbarg · Accepted Answer · 2020-12-06 15:08:22Z

Do not think you need a loop for this, let alone two:

import numpy as np
dif = np.ones(100, dtype = np.int32)
dif[np.cumsum(np.arange(14))] = 3
(1+np.cumsum(dif)).tolist()

output

[4, 7, 8, 11, 12, 13, 16, 17, 18, 19, 22, 23, 24, 25, 26, 29, 30, 31, 32, 33, 34, 37, 38, 39, 40, 41, 42, 43, 46, 47, 48, 49, 50, 51, 52, 53, 56, 57, 58, 59, 60, 61, 62, 63, 64, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 121, 122, 123, 124, 125, 126, 127, 128, 129]

user3452643 · Accepted Answer · 2020-12-06 14:49:03Z

ind_list = []
start_ind = 4
for x in range(0, 6):
        ind_list.append(start_ind)
        for y in range(1, x+1):
            ind_list.append(start_ind + y)
        start_ind = ind_list[len(ind_list)-1]+3
print(ind_list)

You could probably use this. the print function works fine, the list I assume works fairly well for the numbers provided. It appends the new number at the beginning of the loop, with a cotinually longer loop each time for x. I'm assuming the number sequence is 4, 4+3, 4+3+1, 4+3+1+3, 4+3+1+3+1, 4+3+1+3+1+1, 4+3+1+3+1+1+3, ....

Collectives™ on Stack Overflow

How to generate a list of numbers in python

3 Answers 3

1 Comment

Comments

Comments

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

1 Comment

Comments

Comments

Related