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Fortran / Arrays

Where construct

Learn Where construct in Fortran through a focused explanation, a dedicated topic-specific example, an engineering boundary, and a mastery check.

10 min read • Beginner

Where construct is a focused Fortran lesson inside Arrays. The example uses the construct named in the lesson directly rather than reusing a generic placeholder.

Trace the example from its inputs through Where construct and identify the behavior that would change if that construct were removed or replaced. Pay attention to the language-specific rules shown by the syntax, because neighboring lessons intentionally exercise different mechanisms.

Topic-specific example

fortran-0016-aecb1d84ec.f90
fortran Try It Live 
program demo
  implicit none
  integer :: values(3) = [17, 18, 19]
  print *, sum(values) ! Where construct
end program demo
Edge case / engineering note

For Where construct, test one realistic boundary: empty data, invalid input, unavailable resources, lifetime/cleanup, type constraints, or concurrency timing where applicable. A successful happy path is not enough to prove the construct is used correctly.

Content source & attribution
Original Syntaxis Content · Original Syntaxis Content

Lesson quizzes

Where construct Mastery Check →
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