What is Loop: Definition and 1000 Discussions

In computer science, a for-loop (or simply for loop) is a control flow statement for specifying iteration, which allows code to be executed repeatedly. Various keywords are used to specify this statement: descendants of ALGOL use "for", while descendants of Fortran use "do". There are other possibilities, for example COBOL which uses "PERFORM VARYING".
A for-loop has two parts: a header specifying the iteration, and a body which is executed once per iteration. The header often declares an explicit loop counter or loop variable, which allows the body to know which iteration is being executed. For-loops are typically used when the number of iterations is known before entering the loop. For-loops can be thought of as shorthands for while-loops which increment and test a loop variable.
The name for-loop comes from the word for, which is used as the keyword in many programming languages to introduce a for-loop. The term in English dates to ALGOL 58 and was popularized in the influential later ALGOL 60; it is the direct translation of the earlier German für, used in Superplan (1949–1951) by Heinz Rutishauser, who also was involved in defining ALGOL 58 and ALGOL 60. The loop body is executed "for" the given values of the loop variable, though this is more explicit in the ALGOL version of the statement, in which a list of possible values and/or increments can be specified.
In FORTRAN and PL/I, the keyword DO is used for the same thing and it is called a do-loop; this is different from a do-while loop.

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  1. K

    Based loop groups as homogeneous spaces

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  2. S

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  3. U

    Java [JAVA] please tell me this for loop

    Hey guys, I have an ArrayList<String> al = ArrayList<String>(); and I have a textbox, the textbox allows a user to enter a word and that word will be added into the ArrayList. When I print the list out it looks like this [Cat, Dog, Mouse] can you please write out the for loop that I need...
  4. S

    Finding the minimum speed of a loop the loop and finding the height of the hill

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  5. S

    What Determines the Rider's Fate in Different Speed Domains of a Vertical Loop?

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  6. D

    Fortran Creating a Loop for Sum of Digit Squares to Equal 1

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  7. M

    Using the Loop rule to find potential Difference

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  8. D

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  9. L

    Changing part of a name of a variable in a for loop

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  10. M

    Misunderstanding something: circular time dilation loop

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  11. P

    Mathematica Using an If loop in Mathematica

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  12. Ranger Mike

    How Can Closed Loop Drive Systems Achieve Precise 1000 mm Movements?

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  13. I

    Countercurrent condensation loop

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  14. I

    Please help my for loop goes on forever (Matlab) :/

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  15. D

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  16. S

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  17. Roodles01

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  18. haushofer

    Loop Quantum Gravity and Correspondence Principle

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  19. D

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  20. P

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  21. mbrmbrg

    C: Simple for loop is not working

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  22. B

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  23. E

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  24. W

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  25. C

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  26. N

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  27. T

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  28. T

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  29. T

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  30. O

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  31. I

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  32. J

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  33. S

    Can Green's Theorem Simplify Calculations of Magnetic Force in Uniform Fields?

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  34. M

    Mathematica Mathematica: Problem with For loop increments

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  35. B

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  36. JJBladester

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  37. A

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  38. P

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  39. D

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  40. DryRun

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  41. H

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  42. Z

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  43. C

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  44. M

    Assembly Language: How to make a loop skip the first line?

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  45. R

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  46. 5

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  47. N

    Explaination of Quantum Loop Gravity?

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  48. D

    Nested if statement within a do-while loop

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  49. N

    Surface terms in loop integrals (2D)

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  50. M

    MATLAB My Matlab for loop wont output the matrix I need

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