You can learn about Control Statements in Python Programs with Outputs helped you to understand the language better.

Python Programming – Notion Of Iterating Computation (Loops)

Many jobs that are required to be done with the help of a computer are repetitive in nature. For example, the calculation of wages of different workers in a factory is done using the formula (No. of hours worked) x (wage rate). This calculation will be performed by an accountant for each worker every month. Such types of repetitive calculations can easily be done with the help of a program that has a built-in loop. Figure 5.21 shows the flow diagram of the loop statement.

What is a Loop?

A loop is defined as a block of instructions repeated a certain number of times. Figure 5.22 illustrates a flowchart showing the concept of looping. It shows the flowchart for printing values 1, 2, 3…, 20. In Step 5 of Figure 5.22, the current value of A is compared with 21. If the current value of A is less than 21, steps 3 and 4 are repeated. As soon as the current value of A becomes more than 21, the path corresponding to “NO” is followed, and the repetition process stops.

Python Programming – Notion Of Iterating Computation (Loops) chapter 5 img 1

Python Programming – Notion Of Iterating Computation (Loops) chapter 5 img 2

Control Flow

By default, statements in the script are executed sequentially from the first to the last. But the sequential flow can be altered either by conditional execution where a block of one or more statements will be executed if a certain expression is true or by repetitive execution where a block of one or more statements will be repetitively executed as long as a certain expression is true.
Python uses the while and for keywords to constitute a conditional loop, by which repeated execution of a block of statements is done until a Boolean expression is true.

Leave a Reply

Your email address will not be published. Required fields are marked *