Add libvector

Author: Fingercomp

README.md

@@ -14,6 +14,7 @@ Go to the programs' directories to get the docs and the information on what the
 * `camera` — a program that can draw what the Computronics' camera sees.
 * `libthread` — an easy-to-use multithreading library.
 * `libqr` — a QR code generator library.
+* `libvector` — a vector library.
 
 
 ## A not-so-important-but-good-to-know message

libvector/.vector.lua.swp

@@ -0,0 +1,66 @@
+# libvector
+
+This library provides mathematical vectors with unlimited amount of dimensions.
+
+## Authors
+* Ktlo
+
+## Description
+The library returns the function that's called like this: `vector(x: number, y: number, z: number, ...)`.
+
+A vector stores dimensions (and corresponding values) in a table. Each vector also has the `n` field, the amount of dimensions.
+
+```lua
+local vector = require("vector")
+local a = vector(1, 5, 89, 6)
+print(a.n)
+--> 4
+```
+
+All methods create a new vector instead of overriding the old one.
+
+### Arithmetic operations
+```lua
+local vector = require("vector")
+local a = vector(5, 8, 9)
+local b = vector(78, 3, -13, 56)
+
+print(a + b)
+--> {83; 11; -4; 56}
+
+print(a - b)
+--> {-73; 5; 22; -56}
+
+print(a * 8)  -- we could also write this as 8 * a
+--> {40; 64; 72}
+
+print(b / 42)
+--> {1.857; 0.071; -0.310; 1.333}
+
+print(a * b)  -- cross product
+--> {-131; 767; -609}
+
+print(a == b)
+--> false
+
+print(#a, #b)  -- vector lengths
+--> 13.038404810405 96.943282387177
+```
+
+### Methods
+* `vector:tostring([precision: number])` — the same as `tostring(vector)`, but also accepts the optional decimal precision (3 by default).
+* `vector:add(vector2: table): table` — the same as `vector + vector2`.
+* `vector:sub(vector2: table): table` — the same as `vector - vector2`.
+* `vector:mul(vector2: table): table` — the same as `vector * vector2`.
+* `vector:div(number: number): table` — the same as `vector / number`.
+* `vector:len(): number` — the same as `#vector`.
+* `vector:dot(vector2: table): number` — the dot product.
+* `vector:cross(vector2: table): table` — the cross product.
+* `vector:normalize(): table` — returns the normalized vector.
+* `vector:angle(vector2: table): number` — returns the angle between vectors (in radians).
+* `vector:round(): table` — rounds the vector.
+* `vector:eq(vector2: table): boolean` — the same as `vector == vector2`.
+
+## Links
+* [**Pastebin**](http://pastebin.com/mdfDvmps)
+* [The topic on the Russian forums](http://computercraft.ru/topic/1106-)

libvector/README.md

@@ -0,0 +1,207 @@
+local math = require "math"
+local concat = require "table".concat
+local format = require "string".format
+local setmetatable = setmetatable
+local type, error = type, error
+local rawset, rawget = rawset, rawget
+
+-- One of those cases where you really miss the "using" keyword.
+local pow, sqrt, max, floor, acos, sin, cos, modf, pi = math.pow, math.sqrt, math.max, math.floor, math.acos, math.sin, math.cos, math.modf, math.pi
+math = nil
+
+local vector
+
+local function check(o)  -- Vector type check
+  local t = type(o)
+  if not (t == "table" and o.object == "vector") then
+    error("attempt to perform arithmetic on a "..t.." value", 3)
+  end
+end
+
+local __index = {
+  tostring = function(self, f)
+    f = type(f) == "number" and f >= 0 and f or 3
+    f = "%."..f.."f"
+    local r = { }
+    for i = 1, self.n do
+      local n = self[i]
+      r[i] = format(modf(n) == n and "%1d" or f, n)
+    end
+    return "{"..concat(r, "; ").."}"
+  end;
+
+  add = function(a, b)
+    check(a)
+    check(b)
+    local v = { }
+    for i = 1, max(a.n, b.n) do
+      v[i] = (a[i] or 0) + (b[i] or 0)
+    end
+    return vector(v)
+  end;
+
+  sub = function(a, b)
+    check(a)
+    check(b)
+    local v = { }
+    for i = 1, max(a.n, b.n) do
+      v[i] = (a[i] or 0) - (b[i] or 0)
+    end
+    return vector(v)
+  end;
+
+  mul = function(a, b)
+    local t1 = type(a)
+    local t2 = type(b)
+    local v = { }
+    if t1 == "number" then
+      check(b)
+      for i = 1, b.n do
+        v[i] = b[i] * a
+      end
+    elseif t2 == "number" then
+      check(a)
+      for i = 1, a.n do
+        v[i] = a[i] * b
+      end
+    else
+      check(a)
+      check(b)
+      v = a:cross(b)
+    end
+    return vector(v)
+  end;
+
+  div = function(a, b)
+    check(a)
+    local t = type(b)
+    if t ~= "number" then
+      error("attempt to perform arithmetic on a "..t.." value", 3)
+    end
+    local v = { }
+    for i = 1, a.n do
+      v[i] = a[i] / b
+    end
+    return vector(v)
+  end;
+
+  len = function(self)
+    local r = 0
+    for i = 1, self.n do
+      r = r + pow(self[i], 2)
+    end
+    return sqrt(r)
+  end;
+
+  dot = function(a, b)
+    check(a)
+    check(b)
+    local r = 0
+    for i = 1, max(a.n, b.n) do
+      r = r + (a[i] or 0) * (b[i] or 0)
+    end
+    return r
+  end;
+
+  cross = function(a, b)
+    check(a)
+    check(b)
+    local v = {
+      (a[2] or 0) * (b[3] or 0) - (a[3] or 0) * (b[2] or 0);
+      (a[3] or 0) * (b[1] or 0) - (a[1] or 0) * (b[3] or 0);
+      (a[1] or 0) * (b[2] or 0) - (a[2] or 0) * (b[1] or 0);
+    }
+    return vector(v)
+  end;
+
+  normalize = function(self)
+    return self / #self
+  end;
+
+  angle = function(a, b)
+    check(a)
+    check(b)
+    a, b = a:normalize(), b:normalize()
+    return acos(a:dot(b))
+  end;
+
+  rotate = function(v, g, a, b)
+    local r = { }
+    local c, s = cos(g), sin(g)
+    for i = 1, v.n do
+      r[i] = i == a and v[a] * c - v[b] * s or b == i and v[a] * s + v[b] * c or v[i]
+    end
+    return vector(r)
+  end;
+
+  round = function(self, d)
+    local v = { }
+    d = type(d) == "number" and d or 0.5
+    for i = 1, self.n do
+      local a, b = modf(self[i])
+      v[i] = b < d and a or a + 1
+    end
+    return vector(v)
+  end;
+
+  eq = function(a, b)
+    if not (type(a) == "table" and a.object == "vector") or not (type(a) == "table" and a.object == "vector") then
+      return false
+    end
+    local r = true
+    for i = 1, max(a.n, b.n) do
+      if a[i] ~= b[i] then
+        r = false
+        break
+      end
+    end
+    return r
+  end;
+
+  object = "vector";  -- Object type
+}
+
+local meta = {
+  __index = __index;
+  __tostring = __index.tostring;
+  __add = __index.add;
+  __sub = __index.sub;
+  __mul = __index.mul;
+  __div = __index.div;
+  __len = __index.len;
+  __eq = __index.eq;
+  __newindex = function(self, d, n)
+    local a = type(d)
+    local b = type(n)
+    if not (a == "number" and d == floor(d) and d > 0) then
+      error("invalid dimension type (signed integer expected, got "..(a == "number" and d ~= floor(d) and "float" or a)..")", 2)
+    end
+    if b ~= "number" then
+      error("invalid coordinate type (number expected, got "..b..")")
+    end
+    d = floor(d)
+    for i = 1, d-1 do
+      if not rawget(self, i) then
+        rawset(self, i, 0)
+      end
+    end
+    rawset(self, d, n)
+    rawset(self, "n", d)
+  end;
+}
+
+vector = function(v)  -- Creates a new vector
+  v.n = #v
+  return setmetatable(v, meta)
+end
+
+return function(...)  -- The same as above, but with additional checks
+  local v = { ... }
+  for i=1, #v do
+    local t = type(v[i])
+    if t ~= "number" then
+      error("bad argument #"..i.." (number expected, got "..t..")")
+    end
+  end
+  return vector(v)
+end

libvector/vector.lua

@@ -2,7 +2,7 @@
   ["mc"] = {
     files = {
       ["master/mc/mc.lua"] = "/bin",
-      ["master/mc/README.md"] = "/share/doc"
+      ["master/mc/README.md"] = "/share/doc/mc"
     },
     name = "Midday Commander",
     description = "A file commander, similar to Midnight Commander and Norton Commander.",
@@ -13,7 +13,7 @@
     files = {
       ["master/holo-editor/holo-editor.lua"] = "/bin",
       ["master/holo-editor/holo-viewer.lua"] = "/bin",
-      ["master/holo-editor/README.md"] = "/share/doc"
+      ["master/holo-editor/README.md"] = "/share/doc/holo-editor"
     },
     name = "Hologram Editor and Viewer",
     description = "Allows to easily create, edit, and show holograms.",
@@ -23,7 +23,7 @@
   ["obj"] = {
     files = {
       ["master/obj/obj.lua"] = "/lib",
-      ["master/obj/README.md"] = "/share/doc"
+      ["master/obj/README.md"] = "/share/doc/obj"
     },
     name = "OBJ",
     description = "3D models drawing library for OpenGlasses.",
@@ -33,7 +33,7 @@
   ["libforms"] = {
     files = {
       ["master/libforms/forms.lua"] = "/lib",
-      ["master/libforms/README.md"] = "/share/doc"
+      ["master/libforms/README.md"] = "/share/doc/libforms"
     },
     name = "Forms",
     description = "A lightweight and easy-to-use GUI library.",
@@ -43,7 +43,7 @@
   ["lava-runner"] = {
     files = {
       ["master/lava-runner/lava-runner.lua"] = "/bin",
-      ["master/lava-runner/README.md"] = "/share/doc"
+      ["master/lava-runner/README.md"] = "/share/doc/lava-runner"
     },
     name = "Lava Runner",
     description = "A game for OpenComputers, where one needs to find an exit and not to boil in lava.",
@@ -53,7 +53,7 @@
   ["geomine"] = {
     files = {
       ["master/geomine/geomine.lua"] = "/bin",
-      ["master/geomine/README.md"] = "/share/doc"
+      ["master/geomine/README.md"] = "/share/doc/geomine"
     },
     name = "GeoMine",
     description = "A miner program that uses the Geolyzer to effectively mine the ores.",
@@ -63,7 +63,7 @@
   ["geoglasses"] = {
     files = {
       ["master/geoglasses/geoglasses.lua"] = "/bin",
-      ["master/geoglasses/README.md"] = "/share/doc"
+      ["master/geoglasses/README.md"] = "/share/doc/geoglasses"
     },
     name = "GeoGlasses",
     description = "A program that searches ores, and other high-density blocks, and highlights them on the OpenGlasses' glasses.",
@@ -73,7 +73,7 @@
   ["camera"] = {
     files = {
       ["master/camera/camera.lua"] = "/bin",
-      ["master/camera/README.md"] = "/share/doc"
+      ["master/camera/README.md"] = "/share/doc/camera"
     },
     name = "Camera",
     description = "Draws a image that can be seen by the Computronics' camera",
@@ -83,7 +83,7 @@
   ["libthread"] = {
     files = {
       ["master/libthread/thread.lua"] = "/lib",
-      ["master/libthread/README.md"] = "/share/doc"
+      ["master/libthread/README.md"] = "/share/doc/libthread"
     },
     name = "A threading library",
     description = "Makes it simple to create a program that needs multithreading.",
@@ -93,11 +93,21 @@
   ["libqr"] = {
     files = {
       ["master/libqr/qr.lua"] = "/lib",
-      ["master/libqr/README.md"] = "/share/doc"
+      ["master/libqr/README.md"] = "/share/doc/libqr"
     },
     name = "QR code generator",
     description = "A QR generator library for OpenComputers.",
     authors = "1Ridav",
     repo = "tree/master/libqr"
-  }
+  },
+  ["libvector"] = {
+    files = {
+      ["master/libvector/vector.lua"] = "/lib",
+      ["master/libvector/README.md"] = "/share/doc/libvector"
+    }
+  },
+  name = "Vector library",
+  description = "Provides mathematical vectors.",
+  authors = "Ktlo",
+  repo = "tree/master/libvector"
 }