Compare commits

...

2 Commits

Author SHA1 Message Date
f904019d40 add priority queue 2023-05-31 15:37:47 +08:00
fcbf673dbe add Vec2 2023-05-31 15:37:37 +08:00
4 changed files with 206 additions and 0 deletions

85
src/2d.js Normal file
View File

@ -0,0 +1,85 @@
function sqr(x) {
return x * x;
}
export class Vec2 {
constructor(x, y) {
this.x = x || 0;
this.y = y || 0;
}
add(y) {
return new Vec2(this.x + y.x, this.y + y.y);
}
sub(y) {
return new Vec2(this.x - y.x, this.y - y.y);
}
mul(k) {
return new Vec2(this.x * k, this.y * k);
}
conj() {
return new Vec2(this.x, -this.y);
}
yx() {
return new Vec2(this.y, this.x);
}
complexMul(y) {
return new Vec2(this.x * y.x - this.y * y.y, this.x * y.y + this.y * y.x);
}
complexInv() {
return this.conj().mul(1 / this.norm());
}
complexDiv(y) {
return this.complexMul(y.complexInv());
}
addTo(y) {
this.x += y.x;
this.y += y.y;
}
subTo(y) {
this.x -= y.x;
this.y -= y.y;
}
mulTo(k) {
this.x *= k;
this.y *= k;
}
equal(y) {
return this.x == y.x && this.y == y.y;
}
arg() {
return Math.atan2(this.y, this.x);
}
abs() {
return Math.sqrt(this.norm());
}
norm() {
return sqr(this.x) + sqr(this.y);
}
clone() {
return new Vec2(this.x, this.y);
}
dot(y) {
return this.x * y.x + this.y * y.y;
}
cross(y) {
return this.x * y.y - this.y * y.x;
}
}

View File

@ -0,0 +1,51 @@
export class PriorityQueue {
constructor() {
this.val = [null];
}
push(value, priority) {
if (priority == null) {
priority = value;
}
this.val.push([value, priority]);
let id = this.val.length - 1;
while (id > 1 && this.val[id][1] > this.val[id >>> 1][1]) {
const kid = id >>> 1;
[this.val[id], this.val[kid]] = [this.val[kid], this.val[id]];
id = kid;
}
return this;
}
pop() {
let lv = this.val.pop();
if (this.val.length == 1) { return lv; }
let res = this.val[1];
this.val[1] = lv;
let id = 1;
while (id * 2 < this.val.length) {
if (this.val[id][1] > this.val[id * 2][1] && (id * 2 + 1 >= this.val.length || this.val[id][1] > this.val[id * 2 + 1][1])) {
break;
}
let kid = id * 2 + 1 >= this.val.length || this.val[id * 2][1] > this.val[id * 2 + 1][1] ? id * 2 : id * 2 + 1;
[this.val[id], this.val[kid]] = [this.val[kid], this.val[id]];
id = kid;
}
return res;
}
top() {
return this.val[1];
}
size() {
return this.val.length - 1;
}
empty() {
return this.size() == 0;
}
}

52
tests/2d.test.js Normal file
View File

@ -0,0 +1,52 @@
import assert from 'node:assert';
import { Vec2 } from '../src/2d.js';
describe('Vec2', function () {
it('construct', function() {
let p = new Vec2(1, 2);
assert.equal(p.x, 1);
assert.equal(p.y, 2);
});
it('equal', function() {
assert.ok((new Vec2(1, 2)).equal(new Vec2(1, 2)));
assert.ok(!(new Vec2(1, 2)).equal(new Vec2(1, 12)));
});
it('vector calculation', function() {
let p = new Vec2(2, 4), q = new Vec2(3, 1);
assert.ok(p.add(q).equal(new Vec2(5, 5)));
assert.ok(p.sub(q).equal(new Vec2(-1, 3)));
assert.ok(p.mul(1.5).equal(new Vec2(3, 6)));
assert.ok(p.yx().equal(new Vec2(4, 2)));
});
it('vector calculation(TO)', function () {
let p = new Vec2(2, 4), q = new Vec2(3, 1);
p.addTo(q);
assert.ok(p.equal(new Vec2(5, 5)));
p.subTo(q);
assert.ok(p.equal(new Vec2(2, 4)));
p.mulTo(1.5);
assert.ok(p.equal(new Vec2(3, 6)));
});
it('abs & norm', function() {
let p = new Vec2(3, 4);
assert.equal(p.abs(), 5);
assert.equal(p.norm(), 25);
});
it('complex calculation', function() {
let p = new Vec2(1, 4), q = new Vec2(0, 1);
assert.ok(p.complexMul(q).equal(new Vec2(-4, 1)));
assert.ok(p.complexDiv(q).equal(new Vec2(4, -1)));
assert.equal(q.arg(), Math.PI / 2);
});
it('dot & cross product', function() {
let p = new Vec2(2, 4), q = new Vec2(3, 1);
assert.equal(p.dot(q), 10);
assert.equal(p.cross(q), -10);
});
});

View File

@ -0,0 +1,18 @@
import assert from 'node:assert';
import { PriorityQueue } from '../src/misc/priority_queue.js';
describe('PriorityQueue', function () {
it('everything', function() {
let q = new PriorityQueue();
q.push(1).push(2).push(-1).push('hi', 4);
assert.equal(q.size(), 4);
assert.equal(q.top()[0], 'hi');
assert.equal(q.pop()[0], 'hi');
assert.equal(q.pop()[0], 2);
assert.equal(q.pop()[0], 1);
assert.equal(q.pop()[0], -1);
assert.ok(q.empty());
});
});