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fix permutation docs

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consolidate "line/segment/ray" functions to just "line" with bounded option
add RAY, LINE and SEGMENT constants
This commit is contained in:
Adrian Mariano
2021-09-09 18:32:58 -04:00
parent a651e191b4
commit 14ae1795bb
8 changed files with 177 additions and 314 deletions
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15
arrays.scad
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@@ -1369,11 +1369,10 @@ function triplet(list, wrap=false) =
// Function: combinations()
// Usage:
// list = combinations(l, [n]);
// for (p = combinations(l, [n])) ...
// Topics: List Handling, Iteration
// See Also: idx(), enumerate(), pair(), triplet(), permutations()
// Description:
// Returns an ordered list of every unique permutation of `n` items out of the given list `l`.
// Returns a list of all of the (unordered) combinations of `n` items out of the given list `l`.
// For the list `[1,2,3,4]`, with `n=2`, this will return `[[1,2], [1,3], [1,4], [2,3], [2,4], [3,4]]`.
// For the list `[1,2,3,4]`, with `n=3`, this will return `[[1,2,3], [1,2,4], [1,3,4], [2,3,4]]`.
// Arguments:
@@ -1395,21 +1394,17 @@ function combinations(l,n=2,_s=0) =
// Function: permutations()
// Usage:
// list = permutations(l, [n]);
// for (p = permutations(l, [n])) ...
// Topics: List Handling, Iteration
// See Also: idx(), enumerate(), pair(), triplet(), combinations()
// Description:
// Returns an ordered list of every unique permutation of `n` items out of the given list `l`.
// For the list `[1,2,3,4]`, with `n=2`, this will return `[[1,2], [1,3], [1,4], [2,3], [2,4], [3,4]]`.
// For the list `[1,2,3,4]`, with `n=3`, this will return `[[1,2,3], [1,2,4], [1,3,4], [2,3,4]]`.
// Returns a list of all of the (ordered) permutation `n` items out of the given list `l`.
// For the list `[1,2,3]`, with `n=2`, this will return `[[1,2],[1,3],[2,1],[2,3],[3,1],[3,2]]`
// For the list `[1,2,3]`, with `n=3`, this will return `[[1,2,3],[1,3,2],[2,1,3],[2,3,1],[3,1,2],[3,2,1]]`
// Arguments:
// l = The list to provide permutations for.
// n = The number of items in each permutation. Default: 2
// Example:
// pairs = permutations([3,4,5,6]); // Returns: [[3,4],[3,5],[3,6],[4,5],[4,6],[5,6]]
// triplets = permutations([3,4,5,6],n=3); // Returns: [[3,4,5],[3,4,6],[3,5,6],[4,5,6]]
// Example(2D):
// for (p=permutations(regular_ngon(n=7,d=100))) stroke(p);
// pairs = permutations([3,4,5,6]); // // Returns: [[3,4],[3,5],[3,6],[4,3],[4,5],[4,6],[5,3],[5,4],[5,6],[6,3],[6,4],[6,5]]
function permutations(l,n=2) =
assert(is_list(l), "Invalid list." )
assert( is_finite(n) && n>=1 && n<=len(l), "Invalid number `n`." )