dotSCAD/docs/lib3x-binary_search.md

binary_search

A general-purpose function to search a value in a sorted list.

Since: 3.3

Parameters

• sorted : The sorted list.
• target : The target element or a function literal that returns a negative integer, zero, or a positive integer as the element is less than, equal to, or greater than the value you want to search.
• lo : Default to 0. The lower bound to be searched.
• hi : Default to the end of the list. The higher bound to be searched.

Examples

use <util/sorted.scad>
use <util/binary_search.scad>

points = [[1, 1], [3, 4], [7, 2], [5, 2]];
lt = sorted(points); // [[1, 1], [3, 4], [5, 2], [7, 2]]

assert(binary_search(lt, [7, 2]) == 3);

xIs5 = function(elem) elem[0] - 5;
assert(binary_search(lt, xIs5) == 2);

yIs4 = function(elem) elem[1] - 4;
assert(binary_search(lt, yIs4) == 1);