CS105: Introduction to Python

The input command is necessary when we want to obtain input from a keyboard. So far, variables have been initialized or assigned values within a given Python script, with commands such as:

a=3
b=27
c=a+b

It is often the case that a program requires keyboard input from the user to perform its function. This is exactly what the 'input' command is for. This instruction can output a message, and the program will wait for the user to input a value. Try running this command in the Repl.it run window:

city=input('Enter the name of the city where you are located: ')
print(city)

You should be aware that the input function returns data of type str (that is, string data). If numerical data is required, an extra step must be taken to perform a type conversion using either the int or float commands. Copy and paste this set of commands into the run window and then run code using an input value of 34 when prompted for user input:

temperature_str=input('Enter the temperature: ')
print(temperature_str)
print(type(temperature_str))
print()
temperature_int=int(input('Enter the temperature: '))
print(temperature_int)
print(type(temperature_int))
print()
temperature_float=float(input('Enter the temperature: '))
print(temperature_float)
print(type(temperature_float))
print()

The variable names have been chosen to emphasize and distinguish between their data types. The input command offers the convenience of creating user-defined values within a program. At the same time, it is important to make sure the input value's data type matches the intended use of the variable.