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. Q

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  2. E

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  3. P

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    Hello, i appreciate your help! 1. Homework Statement In this website the drawing of the situation in the first exercise can be seen, for better understanding. http://wwwprof.uniandes.edu.co/~gtel...s-semana10.pdf The problem asks me to determine the minimum height h to allow an...
  4. P

    Non conservative energies on a Loop

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  5. C

    Can loop quantum gravity tell us something about the phenomena of the neutrinos?

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  6. E

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  7. E

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  8. N

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  9. N

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  10. N

    Did I do my loop analysis correctly?

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  11. S

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  12. C

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  13. C

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  14. H

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  15. L

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  16. reddvoid

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  17. D

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  18. tom.stoer

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  19. S

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  20. marcus

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  21. N

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  22. C

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  23. M

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  24. L

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  25. L

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  26. F

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  27. A

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  28. M

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  29. B

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  30. M

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  31. H

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  32. I

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  33. I

    Determine the magnitude of the net force on the loop.

    Homework Statement A rectangular loop wire is placed next to a straight wire, as shown in the figure. There is a current of 3.5 A in both wire. Figure: http://www.flickr.com/photos/65980314@N06/6020832477/ Homework Equations F = ((mu(0)*I1*I2) / (2*pi*r)) * L force in terms of...
  34. P

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  35. wolram

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  36. R

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  37. R

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  38. wolram

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  39. A

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  40. P

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  41. W

    Problem with For Loop - Any Help Appreciated

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  42. 0

    What is the Magnetic Field at the Center of a Square Loop Carrying a Current?

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  43. Jim Kata

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  44. L

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  45. F

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  46. S

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  47. R

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  48. G

    Another Noob MATLAB Question - For loop

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  49. jaumzaum

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  50. R

    Calculating current in a loop, given torque and magn. field

    Homework Statement In the figure below, a rectangular loop carrying current lies in the plane of a uniform magnetic field of magnitude 0.038 T. The loop consists of a single turn of flexible conducting wire that is wrapped around a flexible mount such that the dimensions of the rectangle can...
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