Feat: random variable generator done!

mapytex/calculus/core/random/__init__.py

@@ -49,6 +49,7 @@ Tree with RdLeaf replaced by generated values
 
 """
 
+from random import choice
 from .leaf import RdLeaf
 
 def extract_rdleaf(tree):
@@ -124,3 +125,95 @@ def replace_rdleaf(tree, computed_leafs):
             return leaf
     return tree.map_on_leaf(replace)
 
+
+def random_generator(rd_variables,
+                     conditions = [],
+                     rejected = [0],
+                     min_max = (-10, 10),
+                     variables_scope = {}):
+    """ Generate random variables
+
+    :param rd_variables: list of random variables to generate
+    :param conditions: condition over variables
+    :param rejected: Rejected values for the generator (default [0])
+    :param min_max: (min, max) limits in between variables will be generated
+    :param variables_scope: rejected and min_max define for individual variables
+    :return: dictionnary of generated variables
+
+    :example:
+    >>> gene = random_generator(["a", "b"], 
+    ...                  ["a > 0"],
+    ...                  [0], (-10, 10),
+    ...                  {"a": {"rejected": [0, 1]},
+    ...                   "b": {"min_max": (-5, 0)}})
+    >>> gene["a"] > 0
+    True
+    >>> gene["a"] != 0
+    True
+    >>> gene["b"] < 0
+    True
+    >>> gene = random_generator(["a", "b"], 
+    ...                  ["a % b == 0"],
+    ...                  [0, 1], (-10, 10))
+    >>> gene["a"] not in [0, 1]
+    True
+    >>> gene["b"] in list(range(-10, 11))
+    True
+    >>> gene["a"] % gene["b"]
+    0
+    """
+    complete_scope = build_variable_scope(rd_variables,
+                                          rejected, min_max,
+                                          variables_scope)
+    choices_list = {v: list(set(range(
+        complete_scope[v]["min_max"][0], complete_scope[v]["min_max"][1]+1)
+                            ).difference(complete_scope[v]["rejected"]))
+                    for v in rd_variables}
+
+    generate_variable = {v: choice(choices_list[v]) for v in rd_variables}
+
+    while not all([eval(c, __builtins__, generate_variable) for c in conditions]):
+        generate_variable = {v: choice(choices_list[v]) for v in rd_variables}
+
+    return generate_variable
+
+def build_variable_scope(rd_variables, rejected, min_max, variables_scope):
+    """ Build variables scope from incomplete one
+
+    :param rd_variables: list of random variables to generate
+    :param rejected: Rejected values for the generator 
+    :param min_max: (min, max) limits in between variables will be generated
+    :param variables_scope: rejected and min_max define for individual variables
+    :return: complete variable scope
+
+    :example:
+    >>> completed = build_variable_scope(["a", "b", "c", "d"], [0], (-10, 10),
+    ...                      {"a": {"rejected": [0, 1]},
+    ...                       "b": {"min_max": (-5, 0)},
+    ...                       "c": {"rejected": [2], "min_max": (0, 5)}})
+    >>> complete = {'a': {'rejected': [0, 1], 'min_max': (-10, 10)}, 
+    ...             'b': {'rejected': [0], 'min_max': (-5, 0)},
+    ...             'c': {'rejected': [2], 'min_max': (0, 5)},
+    ...             'd': {'rejected': [0], 'min_max': (-10, 10)}}
+    >>> completed == complete
+    True
+    """
+    complete_scope = variables_scope
+    for v in rd_variables:
+        try:
+            complete_scope[v]
+        except KeyError:
+            complete_scope[v] = {"rejected": rejected, "min_max": min_max}
+        else:
+            try:
+                complete_scope[v]["rejected"]
+            except KeyError:
+                complete_scope[v]["rejected"] = rejected
+            try:
+                complete_scope[v]["min_max"]
+            except KeyError:
+                complete_scope[v]["min_max"] = min_max
+    return complete_scope
+
+
+