school math calculations

README.md

Math/School stuff

morsecode.txt

A01
B1000
C1010
D100
E0
F0010
G110
H0000
I00
J0111
K101
L0100
M11
N10
O111
P0110
Q1101
R010
S000
T1
U001
V0001
W011
X1001
Y1011
Z1100
101111
200111
300011
400001
500000
610000
711000
811100
911110
011111
.010101
,110011
?001100
/10010
@011010
'011110
!101011
(10110
)101101
&01000
:111000
;101010
=10001
+01010
-100001
_001101
"010010
$000100
00000000

primegen.js

var primesto=n=>{var p=[],i,j;for(i=2;i<n;i++)if((_=>{for(j=0;j<p.length;j++)if(!(i%p[j]))return 0;return 1;})())p.push(i);return p;};

simplegeometry.js

class Point {
  constructor(x,y) {
    this.x=x;
    this.y=y;
  }
}
class Line {
  constructor(point1,point2) {
    this.pt1=point1;
    this.pt2=point2;
    this.slope=(this.pt1.y-this.pt2.y)/(this.pt1.x-this.pt2.x);
    if (this.slope===-Infinity) this.slope=Infinity;
  }
  contains(point) {
    if (this.slope===Infinity) {
      return this.pt1.x=point.x;
    } else {
      return this.pt1.y-point.y===this.slope*(this.pt1.x-point.x);
    }
  }
  intersect(line) {
    if (this.slope===line.slope) return null;
    if (this.slope===Infinity) {
      return new Point(this.pt1.x,line.yAt(this.pt1.x));
    } else if (line.slope===Infinity) {
      return new Point(line.pt1.x,this.yAt(line.pt1.x));
    } else {
      var x=(this.slope*this.pt1.x-line.slope*line.pt1.x+line.pt1.y-this.pt1.y)/(this.slope-line.slope);
      return new Point(Math.round(x*10000)/10000,Math.round((this.slope*(x-this.pt1.x)+this.pt1.y)*10000)/10000);
    }
  }
  xAt(y) {
    if (this.slope===0) return NaN;
    else return (y-this.pt1.y)*this.slope+this.pt1.x;
  }
  yAt(x) {
    if (this.slope===Infinity) return NaN;
    else return this.slope*(x-this.pt1.x)+this.pt1.y;
  }
}
class Rectangle {
  constructor(point1,point2) {
    this.minpt=new Point(Math.min(point1.x,point2.x),Math.min(point1.y,point2.y));
    this.maxpt=new Point(Math.max(point1.x,point2.x),Math.max(point1.y,point2.y));
    this.top=new Line(new Point(this.minpt.x,this.minpt.y),new Point(this.maxpt.x,this.minpt.y));
    this.left=new Line(new Point(this.minpt.x,this.minpt.y),new Point(this.minpt.x,this.maxpt.y));
    this.right=new Line(new Point(this.maxpt.x,this.minpt.y),new Point(this.maxpt.x,this.maxpt.y));
    this.bottom=new Line(new Point(this.minpt.x,this.maxpt.y),new Point(this.maxpt.x,this.maxpt.y));
  }
  contains(point) {
    return point.x>=this.minpt.x&&point.x<=this.maxpt.x&&point.y>=this.minpt.y&&point.y<=this.maxpt.y;
  }
  clip(line) {
    if (this.contains(line.pt1)&&this.contains(line.pt2)) return line;
    if (!this.contains(line.pt1)&&!this.contains(line.pt2)) return null;
    if (line.slope===Infinity) {
      if (!this.contains(new Point(line.pt1.x,this.minpt.y))) return null;
    } else if (line.slope===0) {
      if (!this.contains(new Point(this.minpt.x,line.pt1.y))) return null;
    } else if (!this.contains(line.intersect(this.top))&&!this.contains(line.intersect(this.left))&&!this.contains(line.intersect(this.right))) return null;
    var pt1=line.pt1.y<line.pt2.y?line.pt1:line.pt2,
    pt2=line.pt1.y<line.pt2.y?line.pt2:line.pt1;
    if (!this.contains(pt1)) {
      pt1=line.intersect(this.top);
      if (!pt1||!this.contains(pt1)) pt1=line.intersect(line.slope<=0?this.right:this.left);
    };
    if (!this.contains(pt2)) {
      pt2=line.intersect(this.bottom);
      if (!pt2||!this.contains(pt2)) pt2=line.intersect(line.slope<=0?this.left:this.right);
    };
    return new Line(pt1,pt2);
  }
}

verticalmotion.js

var aos=(a,b)=>-b/(2*a),
vertex=(a,b,c)=>a*aos(a,b)**2+b*aos(a,b)+c,
xints=(a,b,c)=>[(-b+Math.sqrt(b**2-4*a*c))/(2*a),(-b-Math.sqrt(b**2-4*a*c))/(2*a)],
y=(x,a,b,c)=>a*x**2+b*x+c;