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docs/lib2x-bsearch.md

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+# bsearch
+
+The `search` function is a general-purpose function to find a value or a list of values in a vector. The vector must be sorted by zyx (from the last index to the first one).
+
+**Since:**  2.3
+
+## Parameters
+
+- `sorted` : The sorted vector.
+- `elem` : a list of values.
+- `by` : Can be `"x"`、`"y"`、`"z"`, `"idx"` (Default) or `"vt"`. 
+- `idx` : When `by` is `"idx"`, the value of `idx` is used. The Default value is 0.
+
+## Examples
+
+	use <pixel/px_circle.scad>;
+	use <util/sort.scad>;
+	use <util/bsearch.scad>;
+
+	points = [[1, 1], [3, 4], [7, 2], [5, 2]];
+	sorted = sort(points, by = "vt");
+
+	echo(sorted); //  [[1, 1], [5, 2], [7, 2], [3, 4]]
+	assert(bsearch(sorted, [5, 4], by = "x") == 1);   
+	assert(bsearch(sorted, [5, 4], by = "y") == 3);   
+	assert(bsearch(sorted, [7, 2], by = "vt") == 2);