gistfile1.txt

# -*- coding: utf-8 -*-
"""
Created on Tue Sep 28 10:13:27 2021

@author: pberr
"""

import numpy  as np
import time



mylist=[]
for i in range (0,700):
    mylist.append(i)


myarray = np.empty((600, 600))
for x in range (0,600):
    for y in range (0,600):
        p=y+(x*0.25)
        myarray[y,x]=p

myarray=np.asarray(myarray)

# object here is to produce an array of 600 x 600 with True/False values depending 
# on whether elements in myarray are in mylist.
# The question is - what si teh fastest way to do so?
    
    
# using isin (loop of 10000 used for timing illustration)

start = time.time()

for i in range (0,10):
 s1=np.isin(myarray,mylist)
 
end = time.time()


print (s1[0][0:10])
print (s1[1][0:10])
print (s1[2][0:10])

print("time taken = ",(end-start))
   
def quickisin(array,mylist):
    mylist=set(mylist)
    
    p=[]
    t=len(array)
    
    for j in range (0,t):
        h=array[j]
        s1 = [item in mylist for item in h]
        p.append(s1)
    
    q=np.asarray(p)
     
    return q    

start = time.time()

for i in range (0,10):
 s1=quickisin(myarray,mylist)
 
end = time.time()

print (s1[0][0:10])
print (s1[1][0:10])
print (s1[2][0:10])

print("time taken = ",(end-start))