This is the 17th day of my participation in the First Challenge 2022

Today I would like to share some tips on using Python. I have been using Python for almost 2 years from AI. I have also encountered problems and tried some solutions. Feel the following introduction of solutions are more practical, but also hope to help you.

The difference between two lists

We now have two lists, Models and object_Detections

models = ['fastRCNN'.'YOLO'.'mask-rcnn'.'deeplab'.'FCN']
object_detections = ['fastRCNN'.'YOLO'.'mask-rcnn']
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We want to find some models, which is models and object_Detections, where this element is present in models but not object_Detections

models_set = set(models)
object_detections_set = set(object_detections)

segmentation = list(models_set.symmetric_difference(object_detections_set))
print(segmentation)
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Calculate the amount of memory used by Python objects

Whenever any data structure (such as a list, dictionary, or any object) is used to store values or records, check the amount of memory the data structure takes up. A good practice to see how much memory is being used by a data structure is to use sys. getSizeof to return the sizeof the object, in bytes.

import sys

object_detections = ['fastRCNN'.'YOLO'.'mask-rcnn']

print("size of list = ",sys.getsizeof(object_detections))
#Memory: 4076 kilobyte(s)
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List to heavy

In many cases, duplicate elements need to be removed from the list. We usually use a set that is automatically deduplicated. No duplicate elements are allowed in a set.

listNumbers = [1.2.2.5.5.5.6.7.8]
print("Original= ", listNumbers)

listNumbers = list(set(listNumbers))
print("After removing duplicate= ", listNumbers)
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Original=  [1.2.2.5.5.5.6.7.8]
After removing duplicate=  [1.2.5.6.7.8]
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How do I compare two lists effectively

Usually we need to compare two lists to see if they are the same,

from collections import Counter

one = [1.5.3.7.9]
two = [9.1.3.5.7]

print("Compare if two lists are the same.", Counter(one) == Counter(two))
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  • Object that Hashable can usecollections.Counter
  • You can also usesorted()Sort them and see if they’re the same

The check list contains only one element

To check whether a list contains only one element, use a little trick: count the number of occurrences of an element. If count is the same length as the list, all elements in the list are consistent.

a = [3.3.3.3]
print("All element are duplicate in listOne", a.count(a[0= =])len(a))

b = [3.3.3.2]
print("All element are duplicate in listTwo", b.count(b[0= =])len(b))
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Computing function time

In general, we need to know the elapsed time of our function to measure its performance.

import time startTime = time.time() 
# Your code
endTime = time.time() 
totalTime = endTime - startTime 
print("Total time required to execute code is= ", totalTime)
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Deconstruction dictionary

If you are familiar with the new ES6 features of JS, you should be familiar with the following syntax. Deconstruction is sort of taking the elements out of the container one by one.

networkOne = {1: 'AlexNet'.2: "ResNet".3:"DenseNet"}
networkTwo= {2: 'ViT'.4: "Transformer"}

networkThird = {**networkOne, **networkTwo}
print(networkThird)
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{1: 'AlexNet'.2: 'ViT'.3: 'DenseNet'.4: 'Transformer'}
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