Re: How to store a boolean expression (parse tree) in a model?

I suggest you have a look at the "Trees and Graph" section of the

Django Packages website[0]. I've personally used MPTT and Treebeard

in the past without too much trouble.

You could also a field able to store composite data structures

such as JSONField or even a dedicated PostgreSQL type[1] to efficiently store

such data.

Cheers,

Simon

[0] https://djangopackages.org/grids/g/trees-and-graphs/

[1] https://www.postgresql.org/docs/current/sql-createtype.html

Le mardi 18 février 2020 18:13:39 UTC-5, test a écrit :

Let's say I have:

Calculator #1:

Expression: (True AND False) AND (True OR False)

This expression should be a child of some calculator. 

class Calculator(models.Model):

name = ...

class Expression(models.Model):

parent = models.ForeignKey(Calculator)

boolean = AND or OR

sub_exp1 = models.ForeignKey(Expression)

sub_exp2 = models.ForeignKey(Expression)

When I query all the expressions for the Calculator #1, I should get all the subexpressions.

1 AND 2 5

2 AND 3 4

3 leaf node of True 

4 lead node of False

5 OR 6 7

6 leaf node of True

7 leaf node of False

From this, I can quickly apply my parse tree.

How would I display the base case/leaf nodes in my model? Also, is there a better way?

Thanks, I would really appreciate any help

--
You received this message because you are subscribed to the Google Groups "Django users" group.
To unsubscribe from this group and stop receiving emails from it, send an email to django-users+unsubscribe@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/django-users/5ec92ddf-78b7-477a-aa0c-c7bc2a5ef005%40googlegroups.com.