Unknown source of error in while command in python - python

I am testing a code written and posted on the website
http://foreverlearning.altervista.org/genetic-programming-symbolic-regression-pt-3/
The portion of the code is located at the bottom part of the webpage. When running the test code mainpova.py, I am getting the syntax error.
The syntax error is,
python mainprova4.py
Traceback (most recent call last):
File "mainprova4.py", line 1, in <module>
import generation as gn
File "/home/adam/DocumentsNew2/MathCode/SymbolicRegression/WebpageCode /generation.py", line 46
while len(selectedMembers) < numMembers: indexSelected = 0 while rnd.randint(0, 100) > int(pickProb * 100) and indexSelected != len(self.membersWithErrors) - 1:
^
SyntaxError: invalid syntax
The indicator ' ^ ' is actually located below e of the while word located before rnd.randint. This is for the portion of the code,
def getMembersForReproduction(self, numMembers, pickProb):
""" Returns a certain number of distinct members from the generation.
The first member is selected with probability pickProb. If it's not chosen, the
second member is selected with probability pickProb, and so on. """
selectedMembers = []
while len(selectedMembers) < numMembers: indexSelected = 0 while rnd.randint(0, 100) > int(pickProb * 100) and indexSelected != len(self.membersWithErrors) - 1:
indexSelected += 1
memberWithErrorSelected = self.membersWithErrors[indexSelected]
if memberWithErrorSelected[0] not in selectedMembers:
selectedMembers.append(memberWithErrorSelected[0])
return selectedMembers
The source code has been corrected for lesser and greater typos. Other than that the code is fine except for the while loop. What is the source for the syntax error? The website shows what the output should be.

The formatting is still incorrect. It should look like this:
def getMembersForReproduction(self, numMembers, pickProb):
""" Returns a certain number of distinct members from the generation.
The first member is selected with probability pickProb. If it's not chosen, the
second member is selected with probability pickProb, and so on. """
selectedMembers = []
while len(selectedMembers) < numMembers:
indexSelected = 0
while rnd.randint(0, 100) > int(pickProb * 100) and indexSelected != len(self.membersWithErrors) - 1:
indexSelected += 1
memberWithErrorSelected = self.membersWithErrors[indexSelected]
if memberWithErrorSelected[0] not in selectedMembers:
selectedMembers.append(memberWithErrorSelected[0])
return selectedMembers

I was not aware that indentation plays role in python coding. (I am rookie in python). Yes, it fixed the problem, but another popped out. The error is,
python mainprova4.py
Traceback (most recent call last):
File "mainprova4.py", line 1, in <module>
import generation as gn
File "/home/adam/DocumentsNew2/MathCode/SymbolicRegression/WebpageCode /generation.py", line 105, in <module>
for i in range(0, numCrossover):
NameError: name 'numCrossover' is not defined
The code for this is,
import random as rnd
import generator as gtr
import treeOperations as trop
class Generation(object):
def __init__(self):
self.membersWithErrors = []
def addMember(self, member):
""" Add a tree to the generation """
self.membersWithErrors.append([member, 0])
def setMember(self, member, index):
""" Updates the member at the specified position """
self.membersWithErrors[index] = member
def setError(self, index, error):
""" Sets the error of the member at the specified position """
self.membersWithErrors[index][1] = error
def getMember(self, index):
""" Returns the member at the specified position """
return self.membersWithErrors[index][0]
def getError(self, index):
""" Returns the error of the member at the specified position """
return self.membersWithErrors[index][1]
def size(self):
""" Returns the number of members curently in the generation """
return len(self.membersWithErrors)
def clear(self):
""" Clears the generation, i.e. removes all the members """
self.membersWithErrors.clear()
def sort(self, descending):
""" Sorts the members of the generation according the their score """
self.membersWithErrors.sort(key = lambda l: l[1], reverse = descending)
def getMembersForReproduction(self, numMembers, pickProb):
""" Returns a certain number of distinct members from the generation.
The first member is selected with probability pickProb. If it's not chosen, the
second member is selected with probability pickProb, and so on. """
selectedMembers = []
while len(selectedMembers) < numMembers:
indexSelected = 0
while rnd.randint(0, 100) > int(pickProb * 100) and indexSelected != len(self.membersWithErrors) - 1:
indexSelected += 1
memberWithErrorSelected = self.membersWithErrors[indexSelected]
if memberWithErrorSelected[0] not in selectedMembers:
selectedMembers.append(memberWithErrorSelected[0])
return selectedMembers
def next(self, crossoverPerc, mutationPerc, randomPerc, copyPerc, shouldPruneForMaxHeight, minHeight, maxHeight, minValue, maxValue, variables, operators):
""" It proceeds to the next generation with the help of genetic operations """
oldMembersWithError = self.membersWithErrors
newMembersWithError = []
maxMembers = len(oldMembersWithError)
numCrossover = int(maxMembers * crossoverPerc)
numMutation = int(maxMembers * mutationPerc)
numRandom = int(maxMembers * randomPerc)
numCopy = maxMembers - numCrossover - numMutation - numRandom
# Crossover
for i in range(0, numCrossover):
members = self.getMembersForReproduction(2, 0.3)
m1 = members[0]
m2 = members[1]
newMember = trop.crossover(m1, m2)
newMembersWithError.append([newMember, 0])
# Mutation
for i in range(0, numMutation):
m1 = self.getMembersForReproduction(1, 0.3)[0]
newMembersWithError.append([trop.mutation(m1, minValue, maxValue, variables, operators), 0])
# Random
for i in range(0, numRandom):
newMembersWithError.append([gtr.getTree(minHeight, maxHeight, minValue, maxValue, variables, operators), 0])
# Copy
members = self.getMembersForReproduction(numCopy, 0.3)
for m in members:
newMembersWithError.append([m.clone(), 0])
self.membersWithErrors = newMembersWithError
# No side effects
def pruneTreeForMaxHeight(tree, maxHeight, minValue, maxValue, variables):
""" Returns a new tree that is like the specified tree
but pruned so that its height is maxHeight """
def pruneTreeAux(tree, maxHeight, counter, minValue, maxValue, variables):
if tree.height() == 1:
return tree.clone()
if counter == maxHeight:
return gtr.getLeaf(minValue, maxValue, variables)
pruned1 = pruneTreeAux(tree.op1, maxHeight, counter + 1, minValue, maxValue, variables)
pruned2 = pruneTreeAux(tree.op2, maxHeight, counter + 1, minValue, maxValue, variables)
return tr.BinaryOperatorInternalNode(tree.operator, pruned1, pruned2)
return pruneTreeAux(tree, maxHeight, 1, minValue, maxValue, variables)
# Crossover
for i in range(0, numCrossover):
members = self.getMembersForReproduction(2, 0.3)
m1 = members[0]
m2 = members[1]
newMember = trop.crossover(m1, m2)
if shouldPruneForMaxHeight and newMember.height() > maxHeight:
newMember = trop.pruneTreeForMaxHeight(newMember, maxHeight, minValue, maxValue, variables)
newMembersWithError.append([newMember, 0])
The numCrossover is already defined. What I am missing here?

Related

How to call a module object? [duplicate]

This question already has answers here:
TypeError: 'module' object is not callable
(16 answers)
Closed 1 year ago.
I tried to run this Ant Colony algorithm code (ant_colony.py) in Python:
from threading import Thread
class ant_colony:
class ant(Thread):
def __init__(self, init_location, possible_locations, pheromone_map, distance_callback, alpha, beta, first_pass=False):
Thread.__init__(self)
self.init_location = init_location
self.possible_locations = possible_locations
self.route = []
self.distance_traveled = 0.0
self.location = init_location
self.pheromone_map = pheromone_map
self.distance_callback = distance_callback
self.alpha = alpha
self.beta = beta
self.first_pass = first_pass
self._update_route(init_location)
self.tour_complete = False
def run(self):
while self.possible_locations:
next = self._pick_path()
self._traverse(self.location, next)
self.tour_complete = True
def _pick_path(self):
if self.first_pass:
import random
return random.choice(self.possible_locations)
attractiveness = dict()
sum_total = 0.0
for possible_next_location in self.possible_locations:
pheromone_amount = float(self.pheromone_map[self.location][possible_next_location])
distance = float(self.distance_callback(self.location, possible_next_location))
attractiveness[possible_next_location] = pow(pheromone_amount, self.alpha)*pow(1/distance, self.beta)
sum_total += attractiveness[possible_next_location]
if sum_total == 0.0:
def next_up(x):
import math
import struct
if math.isnan(x) or (math.isinf(x) and x > 0):
return x
if x == 0.0:
x = 0.0
n = struct.unpack('<q', struct.pack('<d', x))[0]
if n >= 0:
n += 1
else:
n -= 1
return struct.unpack('<d', struct.pack('<q', n))[0]
for key in attractiveness:
attractiveness[key] = next_up(attractiveness[key])
sum_total = next_up(sum_total)
import random
toss = random.random()
cummulative = 0
for possible_next_location in attractiveness:
weight = (attractiveness[possible_next_location] / sum_total)
if toss <= weight + cummulative:
return possible_next_location
cummulative += weight
def _traverse(self, start, end):
self._update_route(end)
self._update_distance_traveled(start, end)
self.location = end
def _update_route(self, new):
self.route.append(new)
self.possible_locations.remove(new)
def _update_distance_traveled(self, start, end):
self.distance_traveled += float(self.distance_callback(start, end))
def get_route(self):
if self.tour_complete:
return self.route
return None
def get_distance_traveled(self):
if self.tour_complete:
return self.distance_traveled
return None
def __init__(self, nodes, distance_callback, start=None, ant_count=50, alpha=.5, beta=1.2, pheromone_evaporation_coefficient=.40, pheromone_constant=1000.0, iterations=80):
if type(nodes) is not dict:
raise TypeError("nodes must be dict")
if len(nodes) < 1:
raise ValueError("there must be at least one node in dict nodes")
self.id_to_key, self.nodes = self._init_nodes(nodes)
self.distance_matrix = self._init_matrix(len(nodes))
self.pheromone_map = self._init_matrix(len(nodes))
self.ant_updated_pheromone_map = self._init_matrix(len(nodes))
if not callable(distance_callback):
raise TypeError("distance_callback is not callable, should be method")
self.distance_callback = distance_callback
if start is None:
self.start = 0
else:
self.start = None
#init start to internal id of node id passed
for key, value in self.id_to_key.items():
if value == start:
self.start = key
#if we didn't find a key in the nodes passed in, then raise
if self.start is None:
raise KeyError("Key: " + str(start) + " not found in the nodes dict passed.")
if type(ant_count) is not int:
raise TypeError("ant_count must be int")
if ant_count < 1:
raise ValueError("ant_count must be >= 1")
self.ant_count = ant_count
if (type(alpha) is not int) and type(alpha) is not float:
raise TypeError("alpha must be int or float")
if alpha < 0:
raise ValueError("alpha must be >= 0")
self.alpha = float(alpha)
if (type(beta) is not int) and type(beta) is not float:
raise TypeError("beta must be int or float")
if beta < 1:
raise ValueError("beta must be >= 1")
self.beta = float(beta)
if (type(pheromone_evaporation_coefficient) is not int) and type(pheromone_evaporation_coefficient) is not float:
raise TypeError("pheromone_evaporation_coefficient must be int or float")
self.pheromone_evaporation_coefficient = float(pheromone_evaporation_coefficient)
#pheromone_constant
if (type(pheromone_constant) is not int) and type(pheromone_constant) is not float:
raise TypeError("pheromone_constant must be int or float")
self.pheromone_constant = float(pheromone_constant)
#iterations
if (type(iterations) is not int):
raise TypeError("iterations must be int")
if iterations < 0:
raise ValueError("iterations must be >= 0")
self.iterations = iterations
#other internal variable init
self.first_pass = True
self.ants = self._init_ants(self.start)
self.shortest_distance = None
self.shortest_path_seen = None
def _get_distance(self, start, end):
if not self.distance_matrix[start][end]:
distance = self.distance_callback(self.nodes[start], self.nodes[end])
if (type(distance) is not int) and (type(distance) is not float):
raise TypeError("distance_callback should return either int or float, saw: "+ str(type(distance)))
self.distance_matrix[start][end] = float(distance)
return distance
return self.distance_matrix[start][end]
def _init_nodes(self, nodes):
id_to_key = dict()
id_to_values = dict()
id = 0
for key in sorted(nodes.keys()):
id_to_key[id] = key
id_to_values[id] = nodes[key]
id += 1
return id_to_key, id_to_values
def _init_matrix(self, size, value=0.0):
ret = []
for row in range(size):
ret.append([float(value) for x in range(size)])
return ret
def _init_ants(self, start):
#allocate new ants on the first pass
if self.first_pass:
return [self.ant(start, self.nodes.keys(), self.pheromone_map, self._get_distance,
self.alpha, self.beta, first_pass=True) for x in range(self.ant_count)]
#else, just reset them to use on another pass
for ant in self.ants:
ant.__init__(start, self.nodes.keys(), self.pheromone_map, self._get_distance, self.alpha, self.beta)
def _update_pheromone_map(self):
#always a square matrix
for start in range(len(self.pheromone_map)):
for end in range(len(self.pheromone_map)):
#decay the pheromone value at this location
#tau_xy <- (1-rho)*tau_xy (ACO)
self.pheromone_map[start][end] = (1-self.pheromone_evaporation_coefficient)*self.pheromone_map[start][end]
#then add all contributions to this location for each ant that travered it
#(ACO)
#tau_xy <- tau_xy + delta tau_xy_k
# delta tau_xy_k = Q / L_k
self.pheromone_map[start][end] += self.ant_updated_pheromone_map[start][end]
def _populate_ant_updated_pheromone_map(self, ant):
route = ant.get_route()
for i in range(len(route)-1):
#find the pheromone over the route the ant traversed
current_pheromone_value = float(self.ant_updated_pheromone_map[route[i]][route[i+1]])
#update the pheromone along that section of the route
#(ACO)
# delta tau_xy_k = Q / L_k
new_pheromone_value = self.pheromone_constant/ant.get_distance_traveled()
self.ant_updated_pheromone_map[route[i]][route[i+1]] = current_pheromone_value + new_pheromone_value
self.ant_updated_pheromone_map[route[i+1]][route[i]] = current_pheromone_value + new_pheromone_value
def mainloop(self):
for _ in range(self.iterations):
#start the multi-threaded ants, calls ant.run() in a new thread
for ant in self.ants:
ant.start()
#source: http://stackoverflow.com/a/11968818/5343977
#wait until the ants are finished, before moving on to modifying shared resources
for ant in self.ants:
ant.join()
for ant in self.ants:
#update ant_updated_pheromone_map with this ant's constribution of pheromones along its route
self._populate_ant_updated_pheromone_map(ant)
#if we haven't seen any paths yet, then populate for comparisons later
if not self.shortest_distance:
self.shortest_distance = ant.get_distance_traveled()
if not self.shortest_path_seen:
self.shortest_path_seen = ant.get_route()
#if we see a shorter path, then save for return
if ant.get_distance_traveled() < self.shortest_distance:
self.shortest_distance = ant.get_distance_traveled()
self.shortest_path_seen = ant.get_route()
#decay current pheromone values and add all pheromone values we saw during traversal (from ant_updated_pheromone_map)
self._update_pheromone_map()
#flag that we finished the first pass of the ants traversal
if self.first_pass:
self.first_pass = False
#reset all ants to default for the next iteration
self._init_ants(self.start)
#reset ant_updated_pheromone_map to record pheromones for ants on next pass
self.ant_updated_pheromone_map = self._init_matrix(len(self.nodes), value=0)
#translate shortest path back into callers node id's
ret = []
for id in self.shortest_path_seen:
ret.append(self.id_to_key[id])
return ret
and my module-test file is:
import ant_colony
import math
test_nodes = {0: (0, 7), 1: (3, 9), 2: (12, 4), 3: (14, 11), 4: (8, 11) ,5: (15, 6), 6: (6, 15), 7: (15, 9), 8: (12, 10), 9: (10, 7)}
def distance(start, end):
x_distance = abs(start[0] - end[0])
y_distance = abs(start[1] - end[1])
return math.sqrt(pow(x_distance, 2) + pow(y_distance, 2))
colony = ant_colony(test_nodes, distance)
answer = colony.mainloop()
print(answer)
but when it runs, this error appears:
TypeError: 'module' object is not callable
I tried a lot of ways but they didn't work at all. I tried to test two coordinates instead of distance, I tried to test using arguments and so on, but they did not work. How can I fix it?
You can see that error says module object is not callable. Because when you wrote
import ant_colony
What you did was import that whole module when what you really wanted was just the class
so you can go ahead and do
from ant_colony import ant_colony
and you are good to go!
You are importing module but not a class. Replace this line of code:
import ant_colony
with this line of code:
from ant_colony import ant_colony
What's the difference? In my example you are importing class called ant_colony from file called ant_colony. The first thing is path to file and the second thing is the name of class, function etc.
You have to call it as ant_colony.ant_colony(...) , not ant_colony(...)
See this thread TypeError: 'module' object is not callable

An algorithmic task with triangles

I have a problem with an algorithmic task. There is content of it: "You have ten points on a plane and none three of them are collinear, each pair of different points is connected by line segment, which is green or blue. Calculate how many triangles have sides only in one colour." I tried a solution with n-ary trees but I get repeated triangles with cyclic permutations of integers on the result list.
Patryk, the problem is solvable with n-trees. However, to avoid cyclic permutations you need to skip symmetric line segments. If you create a line segment from 0 -> 1 you do not need to create a segment from 1 -> 0. Below is a complete code which solves the problem with n-trees with the recursive depth-first search. Excuse for Polish names of classes and methods. The interface is in English however. If you analyze the code you will get the point surely.
from random import choice
import copy
class Punkt:
def __init__(self, numer):
self.__numer = numer
self.__odcinki = {}
def dodaj_odcinek_wychodzący(self, punkt_docelowy, kolor):
self.__odcinki[punkt_docelowy] = Odcinek(self.__numer, punkt_docelowy, kolor)
def wez_odcinek_do_punktu_docelowego(self, punkt_docelowy):
return (punkt_docelowy, self.__odcinki[punkt_docelowy].wez_kolor())
def liczba_odcinkow(self):
return len(self.__odcinki)
def wez_kolor_punktu_docelowego(self, punkt_docelowy):
return self.__odcinki[punkt_docelowy].wez_kolor()
def lista_punktow_docelowych(self):
return self.__odcinki.keys()
class Odcinek:
def __init__(self, punkt_zrodlowy, punkt_docelowy, kolor):
self.__punkt_zrodlowy = punkt_zrodlowy
self.__punkt_docelowy = punkt_docelowy
self.__kolor = kolor
def wez_kolor(self):
return self.__kolor
class Structure:
def __init__(self, liczba_punktow=10):
self.__punkty = [Punkt(i)
for i in range(liczba_punktow)]
for i in range(liczba_punktow):
for j in range(i + 1, liczba_punktow):
self.__punkty[i].dodaj_odcinek_wychodzący(j, choice(["green", "blue"]))
# for j in range(liczba_punktow):
# for i in range (j + 1, liczba_punktow):
# self.__punkty[j].dodaj_odcinek_wychodzący(*(self.__punkty[j].wez_odcinek_do_punktu_docelowego(i)))
def wez_punkt(self, numer):
return self.__punkty[numer]
def wez_liczbe_punktow(self):
return len(self.__punkty)
class Search:
def __init__(self, struktura):
self.__s = struktura
def wez_liczbe_punktow(self):
return self.__s.wez_liczbe_punktow()
def wez_punkt(self, numer):
return self.__s.wez_punkt(numer)
def szukaj(self, kolor="green"):
self.__szukany_kolor = kolor
lista_trojkatow = []
liczba_trojkatow = 0
wszystkie_trojkaty = []
for i in range(self.wez_liczbe_punktow()):
lista_odwiedzonych_punktow = [i]
lista_trojkatow = self.szukaj_z_punktu(i,lista_odwiedzonych_punktow,lista_trojkatow)
return len(lista_trojkatow), lista_trojkatow
def wez_szukany_kolor(self):
return self.__szukany_kolor
def szukaj_z_punktu(self, numer, trojkat, lista_trojkatow):
if len(trojkat) == 3: # jeżeli zebraliśmy już trzy punkty to brakuje tylko zamykającego, czwartego
if self.wez_punkt(trojkat[0]).wez_kolor_punktu_docelowego(
trojkat[-1]) == self.wez_szukany_kolor(): # sprawdź czy do punktu zamykającego prowadzi odcinek o szukanym kolorze
trojkat.append(trojkat[0]) # dodaj punkt zamykajacy do trójkąta
lista_trojkatow.append(trojkat) # dodaj trojkąt do listy trójkątów
# return lista_trojkatow # zwróć liste trójkątów obliczonych dotychczas
else:
potomkowie = []
for punkt_docelowy in self.wez_punkt(numer).lista_punktow_docelowych():
if self.wez_punkt(numer).wez_kolor_punktu_docelowego(punkt_docelowy) == self.wez_szukany_kolor():
potomkowie.append(punkt_docelowy)
for potomek in potomkowie:
trojkat_kopia = copy.copy(trojkat)
trojkat_kopia.append(potomek)
lista_trojkatow = self.szukaj_z_punktu(potomek, trojkat_kopia, lista_trojkatow)
return lista_trojkatow
if __name__ == "__main__":
s = Structure()
for source_point in range(s.wez_liczbe_punktow()):
for destination_point in s.wez_punkt(source_point).lista_punktow_docelowych():
print(f"{source_point} -> {destination_point} = {s.wez_punkt(source_point).wez_kolor_punktu_docelowego(destination_point)}")
color = "green"
searching = Search(s)
number_of_triangles, all_triangles = searching.szukaj("green")
print(f"Number of triangles of color {color} = {number_of_triangles}")
print(f"List of all triangles: {all_triangles}")

How to return a copy of an instance of a class?

I am currently practising python on code wars, here is a prompt:
Create a Vector object that supports addition, subtraction, dot products, and norms. So, for example:
a = Vector([1, 2, 3])
b = Vector([3, 4, 5])
c = Vector([5, 6, 7, 8])
a.add(b) # should return a new Vector([4, 6, 8])
a.subtract(b) # should return a new Vector([-2, -2, -2])
a.dot(b) # should return 1*3 + 2*4 + 3*5 = 26
a.norm() # should return sqrt(1^2 + 2^2 + 3^2) = sqrt(14)
a.add(c) # raises an exception
I have written functions add and subtract that pass some of the tests. However, I am running into issues with overwriting my previous list values of 'a' after running the add function. When I go into subtract, the 'a' values in the vector are the summations computed from the previous instance of the add function.
I suspect its due to me running this line of code:
return self.__class__(self.list) causing the instance of the class to overwrite itself.
Kindly please help, I believe I need to return a copy of the instance of the class but don't know how to do it.
class Vector:
def __init__(self, list):
self.list = list #[1,2]
self.copylist = list
def add(self,Vector):
try:
self.list = self.copylist
#take list from other vector
other = Vector.list
#take each value from other Vector and add it to self.list
for index,item in enumerate(Vector.list,0):
self.list[index] = item + self.list[index]
except:
print("Different size vectors")
#return the instance of a class
return self.__class__(self.list)
def subtract(self,Vector):
self.list = self.copylist
other = Vector.list
print(self.list)
print(other)
for index,item in enumerate(Vector.list,0):
self.list[index] = self.list[index] - item
return self.__class__(self.list)
def dot(self,Vector):
self.list = self.copylist
other = Vector.list
#print(self.list)
#print(other)
running_sum =0
for index,item in enumerate(Vector.list,0):
running_sum = running_sum + item * self.list[index]
#print(running_sum, " ", self.list[index], " ", item)
return running_sum
def norm(self):
running_sum = 0
for item in self.list:
running_sum += item**2
return running_sum ** 0.5
def toString(self):
return str(self.list)
`def equals(self,Vector):
return self.list == Vector.list
Here are some of the tests:
a = Vector([1, 2])
b = Vector([3, 4])
test.expect(a.add(b).equals(Vector([4, 6])))
a = Vector([1, 2, 3])
b = Vector([3, 4, 5])
test.expect(a.add(b).equals(Vector([4, 6, 8])))
test.expect(a.subtract(b).equals(Vector([-2, -2, -2]))) #code fails here
test.assert_equals(a.dot(b), 26)
test.assert_equals(a.norm(), 14 ** 0.5)
I think you're making this more complicated than it needs to be. You shouldn't be working with class objects at all. You should just be working with instances of the Vector class. Here's what I think your code should look like:
class Vector:
def __init__(self, initial_elements):
self.elements = list(initial_elements) # make a copy of the incoming list of elements
def add(self, other):
# insure that the two vectors match in length
if len(self.elements) != len(other.elements):
raise Exception("Vector sizes are different")
# copy our elements
r = list(self.elements)
# add the elements from the second vector
for index, item in enumerate(other.elements, 0):
r[index] += item
# return a new vector object defined by the computed elements
return Vector(r)
def subtract(self, other):
# insure that the two vectors match in length
if len(self.elements) != len(other.elements):
raise Exception("Vector sizes are different")
# copy our elements
r = list(self.elements)
# subtract the elements from the second vector
for index, item in enumerate(other.elements, 0):
r[index] -= item
# return a new vector object defined by the computed elements
return Vector(r)
def dot(self, other):
running_sum = 0
for index, item in enumerate(other.elements, 0):
running_sum += item * self.elements[index]
return running_sum
def norm(self):
running_sum = 0
for item in self.elements:
running_sum += item ** 2
return running_sum ** 0.5
def toString(self):
return str(self.elements)
def equals(self, other):
return self.elements == other.elements
def test():
a = Vector([1, 2])
b = Vector([3, 4])
print(a.add(b).equals(Vector([4, 6])))
a = Vector([1, 2, 3])
b = Vector([3, 4, 5])
print(a.add(b).equals(Vector([4, 6, 8])))
print(a.subtract(b).equals(Vector([-2, -2, -2])))
print(a.dot(b) == 26)
print(a.norm() == 14 ** 0.5)
test()
Result:
True
True
True
True
True
The general structure of your code is spot on.
One thing to note is that you shouldn't be using list as a variable name, as it is a type name in Python. Also, you don't want to be passing around Vector as a value. You want to be passing instances of Vector and list, with names that do not conflict with these type names.
My solution assumes you want Vector instances to be immutable, so each of your operations will return a new Vector object. You could also have them not be immutable and have, for example, the add method just add the incoming vector into the target vector without creating a new object. I like keeping them immutable. I've been doing more and more of this "functional style" programming lately, where calls to object methods don't modify the target object (don't have side effects), but rather just return a new object.
I like your use of the test class to do your testing. I chose to not deal with this, and just print the results of each test comparison to see that they all come out to True. I'll leave it to you to restore your tests to using a test object with expect and assert_equals methods.
UPDATE: Here is a more compact way to write your add and subtract methods:
def add(self, other):
# insure that the two vectors match in length
if len(self.elements) != len(other.elements):
raise Exception("Vector sizes are different")
return Vector([self.elements[i] + other.elements[i] for i in range(len(self.elements))])
def subtract(self, other):
# insure that the two vectors match in length
if len(self.elements) != len(other.elements):
raise Exception("Vector sizes are different")
return Vector([self.elements[i] - other.elements[i] for i in range(len(self.elements))])
change:
return self.__class__(self.list)
to:
return self
although this would the same as,
return Vector(self.list)
if the class is more complicated it is better to return self
I think that's the issue, hope it helps :)
also, it is good practice to use different names. you used Vector for the class name as well as many of the inputs of the functions, you will run into problems when you do that.
Please change function toString to str . its' already done.
class Vector :
def __init__(self , lst_vec):
self.lst_vec = lst_vec
def show_vector(self):
return self.lst_vec
def add(self , v ):
size_self = len(self.lst_vec)
size_v = len(v.lst_vec)
new_vector = []
if ( size_self != size_v ):
return Exception("error add")
else:
for i in range(size_self):
new_vector.append(self.lst_vec[i] + v.lst_vec[i])
return Vector(new_vector)
def subtract(self , v ):
size_self = len(self.lst_vec)
size_v = len(v.lst_vec)
new_vector = []
if ( size_self != size_v ):
return Exception("error subtract")
else:
for i in range(size_self):
new_vector.append(self.lst_vec[i] - v.lst_vec[i])
return Vector(new_vector)
def dot(self , v ):
size_self = len(self.lst_vec)
size_v = len(v.lst_vec)
new_vector = []
sum_vec = 0
if ( size_self != size_v ):
return Exception("Vector sizes are different")
else:
for i in range(size_self):
new_vector.append(self.lst_vec[i] * v.lst_vec[i])
for i in range(len(new_vector)):
sum_vec+=new_vector[i]
return sum_vec
def norm (self):
new_vec_sum = 0
for i in range(len(self.lst_vec)):
new_vec_sum +=( self.lst_vec[i] ) **2
return new_vec_sum ** 0.5
def toString(self):
str_self = '('
for i in range(len(self.lst_vec)):
str_self += str(self.lst_vec[i])
if i < (len(self.lst_vec)-1):
str_self+=','
else : pass
str_self+=')'
return str_self
def equals(self , v ):
return self.lst_vec == v.lst_vec
a = Vector([1,2,3])
b = Vector([3,4,5])
c = Vector([5,6,7,8])
print(a.add(b).show_vector())
print( a.add(b).equals(Vector([4,6,8])) )
print(a.subtract(b).show_vector())
print(a.dot(b))
print(a.norm())
print((a.toString() == '(1,2,3)'))
print(c.toString())

Calling a method within other method definitions and 'object has no attribute'

So I've been solving problems utilizing classes for the sake of practicing, but I've been having troubles with calling a method defined in a class, within a method definition of the same class
class Hive:
def __init__(self, arr):
self._arr = arr
self._index = ['Re','Pt','Cc','Ea','Tb','Cm','Ex']
self._number = [0] * 7
self._ratio = []
self._len = len(self._arr)
def number(self):
for i in range(7):
for j in range(self._len):
if self._index[i] == self._arr[j]:
self._number[i] += 1
return self._number
def rate(self):
population = self._arr.number()
for x in range(7):
self._ratio.append(population[x] / self._len)
return self._ratio
def prnt(self):
population2= self._arr.number()
rate2 = self._arr.rate()
for k in range(7):
print("%s %d %.2f" % (self._index[k], population2[k], rate2[k]))
print("Total", str(self._len), "1.00")
arr = input().split()
Colony = Hive(arr)
Colony.prnt()
This ends up with an error that states the following:
Traceback (most recent call last):
File "inee.py", line 33, in <module>
Colony.prnt()
File "inee.py", line 25, in prnt
population2= self._arr.number()
AttributeError: 'list' object has no attribute 'number'
So the only way I could remedy this with my current knowledge was to take care of list assignments outside the method definitions:
class Hive:
def __init__(self, arr):
self._arr = arr
self._index = ['Re','Pt','Cc','Ea','Tb','Cm','Ex']
self._number = [0] * 7
self._ratio = []
self._len = len(self._arr)
def number(self):
for i in range(7):
for j in range(self._len):
if self._index[i] == self._arr[j]:
self._number[i] += 1
return self._number
def rate(self, array):
for x in range(7):
self._ratio.append(array[x] / self._len)
return self._ratio
def prnt(self, array2, array3):
for k in range(7):
print("%s %d %.2f" % (self._index[k], array2[k], array3[k]))
print("Total", str(self._len), "1.00")
arr = input().split()
initial = Hive(arr)
population = initial.number()
rateList = initial.rate(population)
initial.prnt(population, rateList)
This yielded results I wanted, but what's wrong with the first one? Is that not a correct way of calling methods within a method definition within a class?
By callint prnt()-method, you are referring to self._arr. This is not your Hive-object which has the number()-method. It's simply a list. A list does not have a number() attribute. The way you wrote your script you can only call number()-method on the Hive-object itself: self.number(), instead of self._arr.number().
This counts for rate()-method and prnt()-method:
def rate(self):
population = self.number() # <-- here
for x in range(7):
self._ratio.append(population[x] / self._len)
return self._ratio
def prnt(self):
population2 = self.number() # <-- here
rate2 = self.rate() # <-- and here
for k in range(7):
print("%s %d %.2f" % (self._index[k], population2[k], rate2[k]))
print("Total", str(self._len), "1.00")
The second variant you provided cannot work, because you're using number()-method on Hive-object which has no longer a defined attribute number(), because you outsourced it. But you can use it now as a function like this:
>>> arr = ["This", "is", "a", "test", "Re", "Cc", "Tb"]
>>> initial = Hive(arr)
>>> population = number(initial)
>>> print(population)
[1, 0, 1, 0, 1, 0, 0]

Python - high disk usage in SumTree

I've encountered some weird behaviour of my python program. Basically when I tried to create adn fill a SumTree of length larger than 1000, my disk usage increases a lot to ~300MB/s then the programme died.
I'm pretty sure there's no file r/w involved in this process, and the problem is with the add function. The code is shown below.
import numpy as np
class SumTree():
trans_idx = 0
def __init__(self, capacity):
self.num_samples = 0
self.capacity = capacity
self.tree = np.zeros(2 * capacity - 1)
self.transitions = np.empty(self.capacity, dtype=object)
def add(self, p, experience):
tree_idx = self.trans_idx + self.capacity - 1
self.transitions[self.trans_idx] = experience
self.transitions.append(experience)
self.update(tree_idx, p)
self.trans_idx += 1
if self.trans_idx >= self.capacity:
self.trans_idx = 0
self.num_samples = min(self.num_samples + 1, self.capacity)
def update(self, tree_idx, p):
diff = p - self.tree[tree_idx]
self.tree[tree_idx] = p
while tree_idx != 0:
tree_idx = (tree_idx - 1) // 2
self.tree[tree_idx] += diff
def get_leaf(self, value):
parent_idx = 0
while True:
childleft_idx = 2 * parent_idx + 1
childright_idx = childleft_idx + 1
if childleft_idx >= len(self.tree):
leaf_idx = parent_idx
break
else:
if value <= self.tree[childleft_idx]:
parent_idx = childleft_idx
else:
value -= self.tree[childleft_idx]
parent_idx = childright_idx
data_idx = leaf_idx - self.capacity + 1
return leaf_idx, self.tree[leaf_idx], self.transitions[data_idx]
#property
def total_p(self):
return self.tree[0] # the root
#property
def volume(self):
return self.num_samples # number of transistions stored
Here's an example where this SumTree object will be used:
def add(self, experience)
max_p = np.max(self.tree.tree[-self.tree.capacity:])
if max_p == 0:
max_p = 1.0
exp = self.Experience(*experience)
self.tree.add(max_p, exp)
where Experience is a named tuple and self.tree is a Sumtree instance, when I removed the last line the high disk usage disappears.
Can anyone help me with this?
I finally sort this out because each experience is a tuple of namedtuple and I'm creating another namedtuple Experience from it. Fixed by changing experience to a tuple of numpy arrays.

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