Python array find maximum

Python max() and min() – finding max and min in list or array

Python examples to find the largest (or the smallest) item in a collection (e.g. list, set or array) of comparable elements using max() and min() methods.

1. Compute the maximum of the values passed in its argument.
2. Lexicographically largest value if strings are passed as arguments.

1.1. Find largest integer in array

>>> nums = [1, 8, 2, 23, 7, -4, 18, 23, 42, 37, 2] >>> max( nums ) 42 #Max value in array

1.2. Find largest string in array

>>> blogName = ["how","to","do","in","java"] >>> max( blogName ) 'to' #Largest value in array

1.3. Find max key or value

A little complex structure.

>>> prices = < 'how': 45.23, 'to': 612.78, 'do': 205.55, 'in': 37.20, 'java': 10.75 >>>> max( prices.values() ) 612.78 >>> max( prices.keys() ) #or max( prices ). Default is keys(). 'to'

1. compute the minimum of the values passed in its argument.
2. lexicographically smallest value if strings are passed as arguments.

2.1. Find lowest integer in array

>>> nums = [1, 8, 2, 23, 7, -4, 18, 23, 42, 37, 2] >>> min( nums ) -4 #Min value in array

2.2. Find smallest string in array

>>> blogName = ["how","to","do","in","java"] >>> min( blogName ) 'do' #Smallest value in array

2.3. Find min key or value

A little complex structure.

>>> prices = < 'how': 45.23, 'to': 612.78, 'do': 205.55, 'in': 37.20, 'java': 10.75 >>>> min( prices.values() ) 10.75 >>> min( prices.keys() ) #or min( prices ). Default is keys(). 'do'

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Поиск максимального значения в списке на Python

В этой статье мы научимся находить максимальное значение в списке на Python. Для всестороннего понимания вопроса мы рассмотрим использование некоторых встроенных функций, простые подходы, а также небольшие реализации известных алгоритмов.

Сначала давайте вкратце рассмотрим, что такое список в Python и как найти в нем максимальное значение или просто наибольшее число.

Список в Python

В Python есть встроенный тип данных под названием список (list). По своей сути он сильно напоминает массив. Но в отличие от последнего данные внутри списка могут быть любого типа (необязательно одного): он может содержать целые числа, строки или значения с плавающей точкой, или даже другие списки.

Хранимые в списке данные определяются как разделенные запятыми значения, заключенные в квадратные скобки. Списки можно определять, используя любое имя переменной, а затем присваивая ей различные значения в квадратных скобках. Он является упорядоченным, изменяемым и допускает дублирование значений. Например:

 
list1 = ["Виктор", "Артем", "Роман"] list2 = [16, 78, 32, 67] list3 = ["яблоко", "манго", 16, "вишня", 3.4]
 
Далее мы рассмотрим возможные варианты кода на Python, реализующего поиск наибольшего элемента в списке, состоящем из сравниваемых элементов. В наших примерах будут использоваться следующие методы/функции:
 
 
Встроенная функция max()
 
Метод грубой силы (перебора)
 
Функция reduce()
 
Алгоритм Heap Queue (очередь с приоритетом)
 
Функция sort()
 
Функция sorted()
 
Метод хвостовой рекурсии
 
 
№1 Нахождение максимального значения с помощью функции max()
 
Это самый простой и понятный подход к поиску наибольшего элемента. Функция Python max() возвращает самый большой элемент итерабельного объекта. Ее также можно использовать для поиска максимального значения между двумя или более параметрами.
 
В приведенном ниже примере список передается функции max в качестве аргумента.
 
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Find Max And Min In A List Python
 
Working with lists is very common in Python and even more common is to find max and min in a list Python. We will see 3 different methods for each to find min and max in a python list.
 
A list in python is a collection of user-stored data in order. In a list, data can be of any type like string, integer, float, boolean, etc.
 
A list can be created by using square brackets [ ] . Example [1, "a", True] 
A list can have mixed data or can have only one data type. To find max and min in a list, we will work on a list of numbers. A list that has only integers or float values both negative and positive can be used to find max and min.
 
 
 
Find Maximum Value In List
 
To find maximum value in a list we will use 3 different methods.
 
 
Using max() function
 
Finding the maximum value using for loop
 
Using sort() function
 
 
1. Using max() function
 
The max() function is built-in function in Python. It returns the maximum value in a list. It takes a list as an argument and returns the maximum value in the list.
 
The function accepts the list as an argument. Here is the syntax:
 
Let's see an example to find the maximum value in a list.
 
num = [4, 6, 1, 3, 9, 2] # Find the maximum value in the list print(max(num))
 
The max() function can also be used to find the maximum value in a list of strings.
 
To compare the values among strings, the max() function uses their ASCII values. For example, the ASCII value of a is 97 and the ASCII value of z is 122.
 
str = ["a", "b", "c", "d", "e"] print(max(str))
 
In the above example, max of the list is e because the ASCII value of e is 101 which is the highest in the list.
 
Note : max() function does not work on lists of mixed data types.
 
2. Finding the maximum value using for loop
 
You can create your own Python function to find the maximum value in a list using for loop and if condition.
 
Algorithm to find the maximum value in a list
 
 
Create a variable max and assign it to the first element of the list
 
Create a for loop to iterate over the list
 
Check if the current element is greater than max , if yes then assign it to max . Now current element will become the new max .
 
Keep iterating over the list until the end of the list and return max .
 
 
The example below is implemented using the above algorithm.
 
def max_value(list): # set first element as max max = list[0] for i in list: # check if the current element is greater than max if i > max: max = i return max num = [12, 65, 54, 39, 102, 37, 72, 33, 5, -28, 0, 15] print(max_value(num))
 
The above example will find the maximum value in the list and print it.
 
3. Using sort() function: find max
 
The sort() function is another built-in function in python using which we can find the maximum value in a list. The sort() function sorts the list in ascending order, which means smallest stays at the first position and largest stays at the last position.
 
The sort() function takes a list as an argument. TO get the maximum value in a list, you can sort the list and picks the last element of the list.
 
num = [12, 65, 54, 39, 102, 37, 72, 33, 5, -28, 0, 15] # sort the list num.sort() max = num[-1] print(max)
 
The above example sorts the list and then picks the last element from the sorted list which is the maximum value in the list.
 
Find Minimum Value In List
 
Again to find the minimum from a list we can use similar 3 methods but this time just to find the minimum value.
 
 
Using min() function
 
Finding the minimum value using for loop
 
Using sort() function
 
 
1. Using min() function
 
The min() function in python finds the minimum value from a list and returns it. It can work with both numbers and strings as well but not with mixed data types.
 
In the following example, the min() function finds the minimum value in a list of numbers and prints the output.
 
num = [4, 6.4, 1, -3, 0, 2.5] # Find the minimum value in the list print(min(num))
 
The min() function can also find the minimum value in a list of strings by comparing their ASCII values.
 
2. Finding the minimum value using for loop
 
Creating own function to find minimum value in a list by comparing one value to each other.
 
Algorithm to find the minimum value in a list
 
 
Store the first element of the list in a variable min
 
Now loop through the list element and compare elements from each other. If the current element is less than min , then assign it to min . Now you have the new min value.
 
Keep repeating the above steps until the end of the list. At the last min variable will have the actual minimum value of the string.
 
Return min .
 
 
Here is the implementation of the above algorithm.
 
def min_value(list): # set first element as min min = list[0] for i in list: # check if the current element is less than min if i < min: min = i return min num = [12, 65, 54, 39, 102, 37, 72, 33, 5, -28, 0, 15] print(min_value(num))
 
The function will find the minimum value in the list and returns it as output.
 
3. Using sort() function : find min
 
We can again use the sort() function here to sort the elements of a list in ascending order and then picks the first element of the list which is the minimum value.
 
num = [12, 65, 54, 39, 102, 37, 72, 33, 5, -28, 0, 15] min = num[0] print(min)
 
The sort() method sorted the element in ascending order which puts the smallest value in the list at the first position which is -28.
 
Conclusions
 
In this short guide, we have covered 3 methods for each to find max and min in a list python. We have also covered the min(), max() and sort() as in-built functions in python and also created a custom function to find minimum and maximum.
 
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