Python Trainee Interview Questions and Answers

List is mutable, tuple is immutable, dictionary is key-value pair

• List is enclosed in square brackets [], tuple in parentheses (), dictionary in curly braces {}

• List and tuple can store multiple values of any data type, dictionary stores key-value pairs

• List and dictionary are mutable, tuple is immutable

• List and tuple maintain order, dictionary does not

• List allows duplicate values, tuple and dictionary do not

Dataframe is a 2-dimensional labeled data structure with columns of potentially different types.

• Dataframe is a table-like data structure in Python

• It is used for data manipulation and analysis

• It can be created using various sources like CSV, Excel, SQL, etc.

• It is a part of the pandas library in Python

• Example: df = pd.read_csv('data.csv') creates a dataframe from a CSV file

Slicing in Python allows you to extract parts of sequences like lists and strings using a specific syntax.

• Slicing syntax: sequence[start:stop:step]. Example: my_list[1:5:2] returns elements at indices 1, 3.

• Negative indices can be used. Example: my_list[-1] returns the last element.

• Omitting start or stop defaults to the beginning or end. Example: my_list[:3] returns the first three elements.

• Step can be negative for reversing. Example: my_list[::-1] returns the list in reverse ...read more

Use Python's built-in len() function to count characters in a string.

• Use len() function to get the length of the string.

• Consider spaces and special characters in the count.

• Example: s = 'Hello World', char_count = len(s) = 11.