Loop in programming
A loop in programming is a control structure that allows a set of instructions to be repeated multiple times. It is used to automate repetitive tasks and iterate over a collection of data. There are different types of loops, such as for loops, while loops, and do-while loops, each with its own specific use cases and syntax.
4 Key excerpts on "Loop in programming"
eBook - ePubCoding + Math
Strengthen K–5 Math Skills With Computer Science
- Nicol R. Howard(Author)
- 2020(Publication Date)
...However, conditionals can also be modeled effectively through the use of flowcharts or unplugged programming activities. Loops Loops are a mainstay of programming, allowing far more efficiency in programming tasks that must be repeated until a desired result is achieved. For example, if a programmer wants the program to perform a task repeatedly a certain number of times but wants the user to determine that number at runtime, the code would utilize a “for-loop”, accepting user input to set the number of intervals. In Scratch terminology, the coder could use an “ask” block to get user input on how many times the sprite should follow a certain sequence. In that case, the code would contain a “repeat” block to encapsulate the loop containing the blocks in the sequence. This not only prevents the need for repetitive code, but also avoids restricting the loop to some predetermined maximum number of iterations. While loops provide additional power and flexibility to the programmer, they also present a source of potential errors if not used properly. Research has shown the use of endless loops in the Scratch environment as a source of many programming errors, where programs get stuck in never-ending loops (Zhang & Nouri, 2019). Varied understanding of different types of loops, particularly nested loops, have often caused confusion, but this confusion has been less prevalent for Scratch users as compared to text-based languages, since loops are easier to identify in a block-based environment (Mladenovi et al., 2017). Perhaps the best analogy for loops in math is summation notation (∑ 2 i, e.g., meaning the summation of all values of 2 i, starting with 1 and ending with 10); this concept is usually not covered until secondary school...
eBook - ePubTradeStation Made Easy!
Using EasyLanguage to Build Profits with the World's Most Popular Trading Software
- Sunny J. Harris(Author)
- 2011(Publication Date)
- Wiley(Publisher)
...Chapter 11 Loops In This Chapter Introduction For While INTRODUCTION A loop is just as it sounds; it goes around and around until you tell it to stop. A loop defines a group of instructions that will continue executing until a condition is met. The condition being met will cause the loop to stop. A FOR loop will execute a predefined number of times. The predefined number of times is the condition. A WHILE loop will continue to execute while (as long as) the condition is true. Loops allow you to calculate something over a range of values, such as from 1 to 10. Or to take action only while a condition is met, such as: while it is the month of October, only take short trades. Loops allow you to calculate averages, and summations and even count backward. As your programming skills become more proficient, you will find yourself discovering more and more uses for loops. FOR TEMPLATE 1 FOR Value1 = m TO n BEGIN … END; TEMPLATE 2 FOR Value1 = m DOWNTO n BEGIN … END; The FOR command always appears with a BEGIN … END block and is sometimes referred to as a FOR … BEGIN command. The FOR command is always followed by a set of variables that define the starting and ending number of steps to execute the loop. This structure is pretty complex until you get accustomed to it; then it will become second nature, so don’t start worrying yet. Templates for these concepts are shown above. You will specify m and n, and provide code for your task in place of the... s. FOR is always followed by a variable name (Value1 in Figure 11.1). The command tells the computer to perform a set of actions a specified number of times. The variable counts the number of times as it steps through the loop...
eBook - ePubThe Art of Assembly Language Programming Using PIC® Technology
Core Fundamentals
- Theresa Schousek(Author)
- 2019(Publication Date)
- Newnes(Publisher)
...Chapter 5 Looping code Abstract This chapter greets the reader with an introduction to an integrated design environment (IDE,) known as MPLAB X and its internal simulator, SIM. A start to programming loop structures follows. Flowcharts are used to exemplify the order of processes within the loop structures. One flowchart illustrates a “minimum one” process. The second flowchart illustrates a “minimum zero” process, with a change in the order of flowchart elements. Next, a “Sum of Data” program example demonstrates one program implementation. Long conditional branch vectors and page and bank switching are briefly mentioned in the context of using 16C5x series. Keywords Flowcharts; Program loop structures; Page and bank macros; Sum of data; Application notes; Program counter; AN581; AN586; Microchip Chapter Outline Loops Introduction 8-Bit Sum of Data Looped Code Example Partial Straight Line Code Example Macros for Page and Bank Switching (AN586) Long Conditional Branch Vectors (AN581) Word Search: Loops Code Puzzle: Loops Code Further Reading Loops Introduction A program loop is a program structure that causes a segment of code to repeat a fixed number of times. There are four basic segments of code to each loop structure. See program loop flowcharts: Fig. 5.1 (minimum one loop) and Fig. 5.2 (minimum zero loops). 1. Initialize 2. Process 3. Control 4. Conclude Fig. 5.1 Program loop (with minimum one loop) flowchart. Fig. 5.2 Program loop (minimum zero processes) flowchart. Initialization is where the setup values are established. These include the start values of counters, pointers, indexes, and other variables. Counters allow the program to step through the Process section a fixed number of times...
- Dogan Ibrahim(Author)
- 2012(Publication Date)
- Wiley(Publisher)
...The general format of this statement is: where expression 1 sets the initial value of the loop count and this variable is evaluated just once on entry into the loop. Expression 2 is the condition that keeps the loop continuing. This expression is evaluated at each iteration, to check whether or not the loop should continue. Expression 2 is usually a logical or relational operator. Expression 3 is also evaluated at the end of each iteration and this expression changes value that is tested for loop termination. Expression 3 is usually an increment of the loop counter value. The for loop is commonly used with more than one statement. An example is given below, where the loop is repeated 10 times. The initial value of the loop counter i is 0, it is incremented by 1 at each iteration, and the loop continues as long as i is less than 10: Some examples of using the for statement are given below. Example 3.7 Write a program to calculate the squares of numbers between 1 and 49 and store the results in an integer array called Mult. Solution 3.7 The required program is given below. The for loops can easily be nested, as shown in the following example. Here, all elements of a two-dimensional array MyArray are initialised to 0 (assuming that the array dimension is 10). In this example, the inner loop is repeated 10 times for each i value of the outer loop, that is the total number of iterations is 100: The parameters in a for loop can be omitted. There are several variations of the for loop, depending upon which parameter is omitted. Some examples are given below: To create an infinite loop: Setting the initial loop condition outside the loop: To terminate the loop from inside the loop: 3.2.18.7 Premature Termination of a Loop There are cases where we may want to terminate a loop prematurely. This is done using the break statement. When the program encounters this statement, it forces an unconditional jump to outside the loop...
