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Docs: Improve docstring for DDA algorithm #13906

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Docs: Improve docstring for DDA algorithm #13906

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@jeanne-boussonniere jeanne-boussonniere commented Nov 13, 2025

This resolves issue #13905.

@algorithms-keeper algorithms-keeper bot added the awaiting reviews This PR is ready to be reviewed label Nov 13, 2025
ayushHardeniya
ayushHardeniya suggested changes Nov 14, 2025
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Checkout these changes as mentioned on desired places below.

graphics/digital_differential_analyzer_line.py
"""
Draws a line between two points using the DDA algorithm.
This algorithm works by calculating the dx (change in x) and dy;(change in y) and then iteratively
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After dy - ";" is put by mistake, maybe, so remove it or adjust accordingly.

graphics/digital_differential_analyzer_line.py
Draws a line between two points using the DDA algorithm.
This algorithm works by calculating the dx (change in x) and dy;(change in y) and then iteratively
steps along the dominant axis,incrementing the other axis by a fractional amount (the slope).
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The algorithm actually steps along both axes simultaneously. The calculation of the increments ($X_{inc}$ and $Y_{inc}$) ensures that the coordinate along the dominant axis (the one with the larger $\Delta$) is guaranteed to change by exactly 1 unit (or $-1$) in each step, while the coordinate along the non-dominant axis changes by a fractional amount (the slope). The algorithm doesn't "step along" just the dominant axis; it increments both $x$ and $y$ in every single step.

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@ayushHardeniya ayushHardeniya ayushHardeniya requested changes

@mindaugl mindaugl mindaugl approved these changes

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@jeanne-boussonniere @mindaugl @ayushHardeniya