Fortran DO Statements (how many loop times)

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The discussion focuses on the execution count of various Fortran DO statements, specifically analyzing the loops defined in the examples provided. The loops are evaluated based on their index variables and increment values. For instance, the loop "DO irange = -32768, 32767" executes 65536 times, while "DO j = 100, 1, -10" runs 10 times. The statement "DO count = 2, 3, 4" executes once, and "DO index = -4, -7" does not execute at all. The loop "DO i = -10, 10, 10" runs 2 times, confirming the importance of understanding loop increments in Fortran.

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rk2ray
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Hello,

Examining the following DO statements and determining how many times each loop will be executed. Assume that all loop index variables are integers.

(a) DO irange = -32768, 32767
(b) DO j = 100, 1, -10
(c) DO count = 2, 3, 4
(d) DO index = -4, -7

(e) DO i = -10, 10, 10
The loop will take 10 increments and will run 2 times.

Thanks for any help.
 
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