Networking.

2026-01-24 09:57:59 +01:00
parent 1855363661
commit 1a08b3adf0
25 changed files with 1371 additions and 1 deletions
@@ -0,0 +1,148 @@
+import "os" for Process
+
+class Body {
+  construct new(x, y, z, vx, vy, vz, mass) {
+    _x = x
+    _y = y
+    _z = z
+    _vx = vx
+    _vy = vy
+    _vz = vz
+    _mass = mass
+  }
+
+  x { _x }
+  x=(v) { _x = v }
+  y { _y }
+  y=(v) { _y = v }
+  z { _z }
+  z=(v) { _z = v }
+  vx { _vx }
+  vx=(v) { _vx = v }
+  vy { _vy }
+  vy=(v) { _vy = v }
+  vz { _vz }
+  vz=(v) { _vz = v }
+  mass { _mass }
+
+  offsetMomentum(px, py, pz) {
+    _vx = -px / 0.01227246237529089
+    _vy = -py / 0.01227246237529089
+    _vz = -pz / 0.01227246237529089
+  }
+}
+
+class NBody {
+  static init() {
+    var pi = 3.141592653589793
+    var solarMass = 4 * pi * pi
+    var daysPerYear = 365.24
+
+    __bodies = [
+      // Sun
+      Body.new(0, 0, 0, 0, 0, 0, solarMass),
+      // Jupiter
+      Body.new(
+        4.84143144246472090e+00,
+        -1.16032004402742839e+00,
+        -1.03622044471123109e-01,
+        1.66007664274403694e-03 * daysPerYear,
+        7.69901118419740425e-03 * daysPerYear,
+        -6.90460016972063023e-05 * daysPerYear,
+        9.54791938424326609e-04 * solarMass),
+      // Saturn
+      Body.new(
+        8.34336671824457987e+00,
+        4.12479856412430479e+00,
+        -4.03523417114321381e-01,
+        -2.76742510726862411e-03 * daysPerYear,
+        4.99852801234917238e-03 * daysPerYear,
+        2.30417297573763929e-05 * daysPerYear,
+        2.85885980666130812e-04 * solarMass),
+      // Uranus
+      Body.new(
+        1.28943695618239209e+01,
+        -1.51111514016986312e+01,
+        -2.23307578892655734e-01,
+        2.96460137564761618e-03 * daysPerYear,
+        2.37847173959480950e-03 * daysPerYear,
+        -2.96589568540237556e-05 * daysPerYear,
+        4.36624404335156298e-05 * solarMass),
+      // Neptune
+      Body.new(
+        1.53796971148509165e+01,
+        -2.59193146099879641e+01,
+        1.79258772950371181e-01,
+        2.68067772490389322e-03 * daysPerYear,
+        1.62824170038242295e-03 * daysPerYear,
+        -9.51592254519715870e-05 * daysPerYear,
+        5.15138902046611451e-05 * solarMass)
+    ]
+
+    var px = 0
+    var py = 0
+    var pz = 0
+    for (b in __bodies) {
+      px = px + b.vx * b.mass
+      py = py + b.vy * b.mass
+      pz = pz + b.vz * b.mass
+    }
+    __bodies[0].offsetMomentum(px, py, pz)
+  }
+
+  static energy() {
+    var e = 0
+    for (i in 0...__bodies.count) {
+      var bi = __bodies[i]
+      e = e + 0.5 * bi.mass * (bi.vx * bi.vx + bi.vy * bi.vy + bi.vz * bi.vz)
+      for (j in i + 1...__bodies.count) {
+        var bj = __bodies[j]
+        var dx = bi.x - bj.x
+        var dy = bi.y - bj.y
+        var dz = bi.z - bj.z
+        var distance = (dx * dx + dy * dy + dz * dz).sqrt
+        e = e - (bi.mass * bj.mass) / distance
+      }
+    }
+    return e
+  }
+
+  static advance(dt) {
+    for (i in 0...__bodies.count) {
+      var bi = __bodies[i]
+      for (j in i + 1...__bodies.count) {
+        var bj = __bodies[j]
+        var dx = bi.x - bj.x
+        var dy = bi.y - bj.y
+        var dz = bi.z - bj.z
+        var d2 = dx * dx + dy * dy + dz * dz
+        var mag = dt / (d2 * d2.sqrt)
+
+        bi.vx = bi.vx - dx * bj.mass * mag
+        bi.vy = bi.vy - dy * bj.mass * mag
+        bi.vz = bi.vz - dz * bj.mass * mag
+
+        bj.vx = bj.vx + dx * bi.mass * mag
+        bj.vy = bj.vy + dy * bi.mass * mag
+        bj.vz = bj.vz + dz * bi.mass * mag
+      }
+    }
+
+    for (b in __bodies) {
+      b.x = b.x + dt * b.vx
+      b.y = b.y + dt * b.vy
+      b.z = b.z + dt * b.vz
+    }
+  }
+
+  static run(n) {
+    init()
+    System.print(energy())
+    for (i in 0...n) advance(0.01)
+    System.print(energy())
+  }
+}
+
+var start = System.clock
+NBody.run(100000)
+System.print("Elapsed: " + (System.clock - start).toString + "s")