118 lines
3.3 KiB
Python
118 lines
3.3 KiB
Python
#!/usr/bin/env python
|
|
# encoding: utf-8
|
|
|
|
from random import randint
|
|
import re
|
|
|
|
class RdExpression(object):
|
|
"""A generator of random expression builder"""
|
|
|
|
def __init__(self, form, conditions = []):
|
|
"""Initiate the generator
|
|
|
|
:param form: the form of the expression (/!\ variables need to be in brackets {})
|
|
:param conditions: condition on variables (/!\ variables need to be in brackets {})
|
|
|
|
"""
|
|
self._form = form
|
|
self._conditions = conditions
|
|
self._letters = self.get_letters()
|
|
self._gene_varia = {}
|
|
self._gene_2replaced= {}
|
|
|
|
def get_2replaced(self):
|
|
"""Get elements of self._form which will have to be replaced
|
|
:returns: set for elements which have to be replaced
|
|
|
|
"""
|
|
pattern = "\{(.*?)\}" #select inside {} non greedy way
|
|
varia = re.findall(pattern, self._form)
|
|
varia = set(varia)
|
|
self._2replaced = varia
|
|
|
|
return varia
|
|
|
|
def get_letters(self):
|
|
"""Find letters in the form
|
|
:returns: list of letters
|
|
|
|
"""
|
|
v2replaced = self.get_2replaced()
|
|
varia = set()
|
|
|
|
pattern = "([a-zA-Z]+)"
|
|
for v in v2replaced:
|
|
lvar = set(re.findall(pattern, v))
|
|
varia = varia | lvar
|
|
|
|
return varia
|
|
|
|
|
|
def __call__(self, val_min = -10, val_max = 10):
|
|
"""RdExpression once it is initiate act like a function which create random expressions.
|
|
|
|
:param val_min: minimum value random generation
|
|
:param val_max: maximum value random generation
|
|
:returns: an random expression
|
|
|
|
"""
|
|
self.gene_varia(val_min, val_max)
|
|
|
|
while not(self.val_conditions()):
|
|
self.gene_varia(val_min, val_max)
|
|
|
|
return self._form.format(**self._gene_2replaced)
|
|
|
|
def gene_varia(self, val_min = -10, val_max = 10):
|
|
"""RAndomly generates variables/letters
|
|
|
|
"""
|
|
for l in self._letters:
|
|
self._gene_varia[l] = randint(val_min, val_max)
|
|
|
|
for e in self._2replaced:
|
|
self._gene_2replaced[e] = eval(e, globals(), self._gene_varia)
|
|
|
|
def val_conditions(self):
|
|
"""Tells whether or not conditions are validates
|
|
:returns: boolean
|
|
|
|
"""
|
|
if self._conditions != []:
|
|
return eval(" and ".join(self._conditions).format(**self._gene_varia))
|
|
else:
|
|
return True
|
|
|
|
def desc_rdExp(rdExp):
|
|
print("--------------------")
|
|
print("form: ",rdExp._form)
|
|
print("Conditions: ",rdExp._conditions)
|
|
print("Letters: ", rdExp._letters)
|
|
print("2replaced: ", rdExp._2replaced)
|
|
print("Call : ", rdExp())
|
|
print("Gene varia: ", rdExp._gene_varia)
|
|
print("Gene 2replaced: ", rdExp._gene_2replaced)
|
|
print('')
|
|
|
|
|
|
if __name__ == '__main__':
|
|
form = "{a}x + 2*{b}"
|
|
cond = ["{a} + {b} in [1, 2, 3, 4, 5]", "{a} not in [0,1]", "{b} not in [0,1]"]
|
|
rdExp1 = RdExpression(form, cond)
|
|
desc_rdExp(rdExp1)
|
|
rdExp2 = RdExpression(form)
|
|
desc_rdExp(rdExp2)
|
|
form = "{a+a/10}x + {a} + 2*{b}"
|
|
cond = ["{a} + {b} in [1, 2, 3, 4, 5]", "{a} not in [0,1]", "{b} not in [0,1]"]
|
|
rdExp3 = RdExpression(form)
|
|
desc_rdExp(rdExp3)
|
|
|
|
|
|
|
|
|
|
|
|
# -----------------------------
|
|
# Reglages pour 'vim'
|
|
# vim:set autoindent expandtab tabstop=4 shiftwidth=4:
|
|
# cursor: 16 del
|