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A comment on Adobe Photoshop 1.0 Source Code (2013). Parent comment

Re:Adobe Photoshop 1.0 Source Code (2013) by zeckalpha on Tuesday December 23, 2025 @05:55PM (#46370460)
i came from imaginary numbers which were extended to make quaternions.
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Re:Adobe Photoshop 1.0 Source Code (2013) by jibal on Tuesday December 23, 2025 @07:20PM (#46371075)
i, j, k comes from FORTRAN's implicit types -- by default, names starting with I-N are integers and all other names are real.
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Re:Adobe Photoshop 1.0 Source Code (2013) by jcelerier on Tuesday December 23, 2025 @07:41PM (#46371204)
this is much older ; Joseph Fourier was already using "i" and "j" for indices in the 1800s. See page 209: https://www.google.ca/books/edition/OEuvres_de_Fourier_Th%C3...
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Re:Adobe Photoshop 1.0 Source Code (2013) by jibal on Tuesday December 23, 2025 @08:33PM (#46371508)
The context is i, j, k as indices in programs. No doubt FORTRAN was influenced by prior use such as you cite. But in no case does i used as an index come from i designating an imaginary number, which is what I aimed to refute.
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Re:Adobe Photoshop 1.0 Source Code (2013) by zeckalpha on Wednesday December 24, 2025 @08:03PM (#46381117)
Representing dimensions as indexable rows and columns of vectors or matrices was done on paper in the 1800s.
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