def read_problem_from_file(filename):
# Auxiliary function to parse a string of the form (prefix + "rest")
# If string is of this form, it returns True,"rest"
# Otherwise, it returns False,""
def remove_prefix_if_possible(line, prefix):
if line[0:len(prefix)] == prefix:
return True,line[len(prefix):];
else:
return False,"";
try:
file = open(filename, "r");
# Initialize
initial_str = "";
goals_str = "";
t_max_str = "20"; # default value is 20
actions_list = [];
# Read the file line by line
for line in file.readlines():
stripped_line = line.strip();
if stripped_line != "" and stripped_line[0] != '#':
# Lines specifying initial state
match,rest_of_line = remove_prefix_if_possible(stripped_line,"initial: ");
if match:
initial_str = rest_of_line.strip();
if expr(initial_str) == True or expr(initial_str) == None:
initial_str = "[]";
# Lines specifying goals
match,rest_of_line = remove_prefix_if_possible(stripped_line,"goals: ");
if match:
goals_str = rest_of_line.strip();
if expr(goals_str) == True or expr(goals_str) == None:
goals_str = "[]";
# Lines specifying t_max
match,rest_of_line = remove_prefix_if_possible(stripped_line,"t_max: ");
if match:
t_max_str = rest_of_line.strip();
# Lines specifying an action
match,rest_of_line = remove_prefix_if_possible(stripped_line,"action: ");
if match:
action_strs = rest_of_line.split(";");
action = Action(action_strs[0], precond=action_strs[1], effect=action_strs[2]);
if expr(action.precond) == None or expr(action.precond) == True:
action.precond = [];
if expr(action.effect) == None or expr(action.effect) == True:
action.effect = [];
actions_list.append(action);
# Create planning_problem and t_max from the data stored after reading, and return them
planning_problem = PlanningProblem(initial=initial_str, goals=goals_str, actions=actions_list);
t_max = int(t_max_str);
return planning_problem, t_max;
# If exception occurs, print error message and return None,None
except Exception as e:
print("Something went wrong while reading from " + filename + " (" + str(e) + ")");
return None, None;
def read_problem_from_file(filename):
"""
Reads a planning problem (together with an upper bound t_max on the length
of plans for this problem) from a file.
Parameters:
filename (str): Name of the file that is to be read from.
Returns:
((PlanningProblem,int)): Pair with the planning problem and the
bound t_max that are read from the file.
"""
# Auxiliary function to parse a string of the form (prefix + "rest")
# If string is of this form, it returns True,"rest"
# Otherwise, it returns False,""
def remove_prefix_if_possible(line, prefix):
if line[0:len(prefix)] == prefix:
return True,line[len(prefix):]
else:
return False,""
try:
file = open(filename, "r")
# Initialize
initial_str = ""
goals_str = ""
t_max_str = "20" # default value is 20
actions_list = []
# Read the file line by line
for line in file.readlines():
stripped_line = line.strip()
if stripped_line != "" and stripped_line[0] != '#':
# Lines specifying initial state
match,rest_of_line = remove_prefix_if_possible(stripped_line,"initial: ")
if match:
initial_str = rest_of_line.strip()
if expr(initial_str) == True or expr(initial_str) == None:
initial_str = "[]"
# Lines specifying goals
match,rest_of_line = remove_prefix_if_possible(stripped_line,"goals: ")
if match:
goals_str = rest_of_line.strip()
if expr(goals_str) == True or expr(goals_str) == None:
goals_str = "[]"
# Lines specifying t_max
match,rest_of_line = remove_prefix_if_possible(stripped_line,"t_max: ")
if match:
t_max_str = rest_of_line.strip()
# Lines specifying an action
match,rest_of_line = remove_prefix_if_possible(stripped_line,"action: ")
if match:
action_strs = rest_of_line.split(";")
action = Action(action_strs[0], precond=action_strs[1], effect=action_strs[2])
if expr(action.precond) == None or expr(action.precond) == True:
action.precond = []
if expr(action.effect) == None or expr(action.effect) == True:
action.effect = []
actions_list.append(action)
# Create planning_problem and t_max from the data stored after reading, and return them
planning_problem = PlanningProblem(initial=initial_str, goals=goals_str, actions=actions_list)
t_max = int(t_max_str)
return planning_problem, t_max
# If exception occurs, print error message and return None,None
except Exception as e:
print("Something went wrong while reading from " + filename + " (" + str(e) + ")")
return None, None