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Python count

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Python count method is useful to count the total number of times a substring repeated in a given string. In this section, we discuss how to use the count function to perform counting in Python Programming with example.

Python count Function Syntax

The syntax of the count function in Python Programming Language is

String_Value.count(Sub, Start, End)
  • String_Value: Please select a valid String variable, or use the String directly.
  • Sub: This argument is required. Count method looks for this substring inside the String_Value, and if it finds, then it returns the count value.
  • Start: You can specify the starting value here. For example, if you want to count from the middle of a string or at a particular index, you can specify here.
  • End: You can specify the end value here. For example, if you want to count up to the middle of a string, or up to a particular index, you can specify here.

Return Value

The string count function returns an integer value. For example, If we say, ‘Hell World’.count(‘l’, 0, 7) then count function start looking for l inside the ‘Hello World’ and return two because the index position of end value is 7 (i., r)

Python count method Example

The following set of examples help to understand the string count Function in Python Programming Language.

# Python Count Method Example
 
Str1 = 'learn Python at tutorial gateway'
Str2 = 'a'
 
Str3 = Str1.count(Str2)
print("Total Number of a's in String1 = ", Str3)

Str4 = Str1.count(Str2, 6, 25)
print("Total Number of a's in Sliced String1 = ", Str4)

Str5 = Str1.count(Str2, 6, len(Str1))
print("Total Number of a's in Sliced String1 = ", Str5)
 
# Performing Count function directly
Str6 = 'learn Python at tutorial gateway'.count('a', 0, 60)
print("Total Number of a's in String1 = ", Str6)

OUTPUT

Python Count Example 1

ANALYSIS

In this Python example, First, we declared three String variable Str1, Str2, and assigned corresponding value using the following statement.

Str1 = 'learn Python at tutorial gateway'
Str2 = 'a'

The following statement counts the number of times ‘a’ repeated in Str1 string and prints the output.

Str3 = Str1.count(Str2)
print("Total Number of a's in String1 = ", Str3)

The following python count statement slice the string Str1 starting at 6 and up to 25. Within the sliced string, python counts the number of times ‘a’ string repeated and prints the output.

Str4 = Str1.count(Str2, 6, 25)
print("Total Number of a's in Sliced String1 = ", Str4)

It slices the string Str1 starting at 6 and up to End (To find the end value we used the python Len function). Within the sliced string, Python count the number of times ‘a’ repeated.

Str5 = Str1.count(Str2, 6, len(Str1))
print("Total Number of a's in Sliced String1 = ", Str5)

In the below statement, we used the count function directly on String.

Str6 = 'learn Python at tutorial gateway'.count('a', 0, 60)
print("Total Number of a's in String1 = ", Str6)

Python count function Alternative 2

In the interview perspective, they may ask you to display the letter count without using the built-in count method. In this example, we use for loop to iterate the characters present in String.

Str1 = 'learn Python at tutorial gateway'
Str2 = 'a'

count = 0

for char in Str1:
           if char == Str2:
                      count = count + 1
print("Total Number of a's in String1 = ", count)

OUTPUT

Python Count Example 2

ANALYSIS

In this count program, first, We used For Loop to iterate the characters present in Str1 String

for char in Str1:

Within the for loop, we used If statement to check whether each of the string characters is equal to Str2 or not and if it is True, then Count value incremented by 1.

           if char == Str2:
                      count = count + 1

The last print statement prints the Output.

print("Total Number of a's in String1 = ", count)

Python count function Alternative 2

The following example is another alternative method to the String count function in Python Programming Language.

from collections import Counter

Str1 = 'learn Python at tutorial gateway'
Str2 = 'a'

count = Counter(Str1)[Str2]
print("Total Number of a's in String1 = ", count)

OUTPUT

Python Count Example 3