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pythonpython-3.xplotareamontecarlo

object of type 'filter' has no len()

i'm trying to use the simulation of monte carlo in order to calculate the area under the curve (python 3.8) enter image description here

in order to get this plot eventually enter image description here

i tried this code

import random, math

NUM_POINTS = 10000

# Function for which we want to find area from (x=0 to 10).
f = lambda x: 5 * math.sin(6 * x) + 3 * math.sin(2 * x) + 7

# Sample rectangle will be (x,y) such that 0 <= x <= 10 and 0 <= y <= 14.
rect_width = 10
rect_height = 14

# Funcitions to generate samples for x and y respectively.
rand_x = lambda: random.uniform(0, rect_width)
rand_y = lambda: random.uniform(0, rect_height)

# Generate random sample points.
points = [(rand_x(), rand_y()) for i in range(NUM_POINTS)]

# Find points under our function
points_under = filter(lambda point: point[1] <= f(point[0]), points)

# Area = area of domain rectangle * num_points_under/num_points_total
area = rect_width * rect_height * len(points_under)*1.0/len(points)
print ("Estimate of area under the curve:", area)

i'm having this error :

object of type 'filter' has no len()

can anyone help me please ?

Solution

  • Thank you guys , since it is a 2.X python code and i'm using a 3.X version of python , so this tool was helpful in order to convert my code : https://www.pythonconverter.com/