Ask Your Question
1

Generate a list of integer excluding -1, 1 and 0.

asked 2022-07-08 12:17:38 +0100

ryss gravatar image

updated 2022-07-08 14:56:19 +0100

In python, I made this code to pick numbers from a list of numbers, excluding -1, 0 and 1. I can't find the equivalent in sage.

def alea(n, max):
    complete_list = [i for i in range(-max, max+1, 1) if i != 0 and i != -1 and i != 1]
    list = random.sample(complete_list, n)
    return(list)

With Sage, I've done this :

sage: def alea(n, max):
....:     list = [randrange(-max, max+1) for i in range(n)]
....:     return list
....: 
sage: a = alea(5,10)
sage: a
[1, 3, 8, -9, 7]

and as you can see, 1 is in the list of course.

My goal will then be to take for example 4 random numbers a, b, c and d, to make a sum of fractions a/b+c/d, and to generate the answer automatically to make a series of exercises in a document written with latex/sagetex. That's why I need to exclude -1, 0 and 1.

Thanks in advance for your help .

edit :

under sage (jupyter) I have this error

---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-17-8b055ece5ba6> in <module>
      3     list = random.sample(complete_list, n)
      4     return(list)
----> 5 a = alea(Integer(5), Integer(10))
      6 a

<ipython-input-17-8b055ece5ba6> in alea(n, max)
      1 def alea(n, max):
      2     complete_list = [i for i in range(-max, max+Integer(1), Integer(1)) if i != Integer(0) and i != -Integer(1) and i != Integer(1)]
----> 3     list = random.sample(complete_list, n)
      4     return(list)
      5 a = alea(Integer(5), Integer(10))

AttributeError: 'function' object has no attribute 'sample'
edit retag flag offensive close merge delete

Comments

Why do you need an equivalent and what kind? Your Python code should work fine in Sage as is.

Max Alekseyev gravatar imageMax Alekseyev ( 2022-07-08 14:27:43 +0100 )edit

I have an error under Sage, as I show in the "edit" part, and I have some difficulties to understand.

ryss gravatar imageryss ( 2022-07-08 14:56:53 +0100 )edit

You need to add import random before calling random.sample

Max Alekseyev gravatar imageMax Alekseyev ( 2022-07-08 15:05:55 +0100 )edit

Of course ... thanks ... it was so simple. I forgot this.

ryss gravatar imageryss ( 2022-07-08 15:22:10 +0100 )edit

1 Answer

Sort by ยป oldest newest most voted
1

answered 2022-07-08 15:20:56 +0100

tmonteil gravatar image

updated 2022-07-08 15:22:41 +0100

Sage language is Python with some additional functions and classes.

So, Sage has a random function defined, that returns a random number in the interval $[0,1]$:

sage: random()
0.2808809147593442

If you want to use the sample function from the random python module, you just have tom import it before your Python code:

sage: import random

If you do not want to overwrite the random Sage function by the random Python module, you can do:

sage: from random import sample

but then use sample instead of random.sample.

edit flag offensive delete link more

Comments

thx for this answer.

ryss gravatar imageryss ( 2022-07-08 15:25:19 +0100 )edit

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Question Tools

1 follower

Stats

Asked: 2022-07-08 12:17:38 +0100

Seen: 188 times

Last updated: Jul 08 '22

Related questions