Python – Mapping Matrix with Dictionary
Given a Matrix, map its values with dictionary values.
Input : test_list = [[4, 2, 1], [1, 2, 3]], sub_dict = {1 : “gfg”, 2: “best”, 3 : “CS”, 4 : “Geeks”}
Output : [[‘Geeks’, ‘best’, ‘gfg’], [‘gfg’, ‘best’, ‘CS’]]
Explanation : Matrix elements are substituted using dictionary.Attention geek! Strengthen your foundations with the Python Programming Foundation Course and learn the basics.
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Input : test_list = [[4, 2, 1]], sub_dict = {1 : “gfg”, 2: “best”, 4 : “Geeks”}
Output : [[‘Geeks’, ‘best’, ‘gfg’]]
Explanation : Matrix elements are substituted using dictionary.
Method #1 : Using loop
This is brute way in which this task can be performed. In this, we iterate for all the elements of Matrix and map from dictionary.
Python3
# Python3 code to demonstrate working of # Mapping Matrix with Dictionary# Using loop # initializing listtest_list = [[4, 2, 1], [1, 2, 3], [4, 3, 1]] # printing original listprint("The original list : " + str(test_list)) # initializing dictionarysub_dict = {1 : "gfg", 2: "best", 3 : "CS", 4 : "Geeks"} # Using loop to perform required mappingres = []for sub in test_list: temp = [] for ele in sub: # mapping values from dictionary temp.append(sub_dict[ele]) res.append(temp) # printing result print("Converted Mapped Matrix : " + str(res)) |
The original list : [[4, 2, 1], [1, 2, 3], [4, 3, 1]] Converted Mapped Matrix : [['Geeks', 'best', 'gfg'], ['gfg', 'best', 'CS'], ['Geeks', 'CS', 'gfg']]
Method #2 : Using list comprehension
This is yet another way in which this task can be performed. This is just shorthand to above method.
Python3
# Python3 code to demonstrate working of # Mapping Matrix with Dictionary# Using list comprehension # initializing listtest_list = [[4, 2, 1], [1, 2, 3], [4, 3, 1]] # printing original listprint("The original list : " + str(test_list)) # initializing dictionarysub_dict = {1 : "gfg", 2: "best", 3 : "CS", 4 : "Geeks"} # Using list comprehension to perform required mapping# in one line res = [[sub_dict[val] for val in sub] for sub in test_list] # printing result print("Converted Mapped Matrix : " + str(res)) |
The original list : [[4, 2, 1], [1, 2, 3], [4, 3, 1]] Converted Mapped Matrix : [['Geeks', 'best', 'gfg'], ['gfg', 'best', 'CS'], ['Geeks', 'CS', 'gfg']]
