Terminal Input

 

Python

Java

 

The raw_input function displays its argument as a prompt and waits for input.  When the user presses the Enter or Return key, the function returns a string representing the input text.  The programmer then either leaves the string alone or converts it to the type of data that it represents (such as an integer).

 

The input function displays its argument as a prompt and waits for input.  When the user presses the Enter or Return key, the function evaluates the input text and returns its value.  input can thus be used for automatic conversion of numeric inputs.

 

Input a line of text as a string:

 

name = raw_input("Enter your name: ")

 

Input a number (an integer or a float):

 

age = input("Enter your age: ")

 

 

The Scanner class is used for the input of text and numeric data from the keyboard.  The programmer instantiates a Scanner and uses the appropriate methods for each type of data being input.

 

Create a Scanner object attached to the keyboard:

 

Scanner keyboard = new Scanner(System.in);

 

Input a line of text as a string:

 

String s = keyboard.nextLine("Enter your name: ");

 

Input an integer:

 

int i = keyboard.nextInt("Enter your age: ");

 

Input a double:

 

double d = keyboard.nextDouble("Enter your wage: ");

 

Caution: using the same scanner to input strings after numbers can result in logic errors.  Thus, it is best to use separate scanner objects for numbers and text.

 

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