Push src/Math changes.

+ Math\GSeq (Geometric sequence generator)
+ Math\Point (ascended from Misc/Coordinate3D)

CHANGES.txt

@@ -1,98 +1,42 @@
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-r788 | anrdaemon | 2018-04-03 17:58:56 +0300 (Tue, 03 Apr 2018) | 2 lines
+r799 | anrdaemon | 2018-04-15 20:07:18 +0300 (Sun, 15 Apr 2018) | 3 lines
 
-+ Net\Browser initial release.
++ Math:GSeq Use common validity check for $n.
++ Plan for tests.
 
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-r778 | anrdaemon | 2018-03-30 15:17:41 +0300 (Fri, 30 Mar 2018) | 3 lines
+r796 | anrdaemon | 2018-04-08 23:51:15 +0300 (Sun, 08 Apr 2018) | 2 lines
 
-+ Added author.
-+ Put notes/todo under version control.
++ GSeq initial (ok, not) implementation.
 
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-r767 | anrdaemon | 2018-03-19 23:49:28 +0300 (Mon, 19 Mar 2018) | 2 lines
+r795 | anrdaemon | 2018-04-05 22:12:30 +0300 (Thu, 05 Apr 2018) | 2 lines
 
-* Only confirm skipped tests for known mangled characters.
+- Reduce the number of "new static" calls to absolutely required.
 
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-r765 | anrdaemon | 2018-03-14 01:25:26 +0300 (Wed, 14 Mar 2018) | 2 lines
+r794 | anrdaemon | 2018-04-05 18:22:37 +0300 (Thu, 05 Apr 2018) | 2 lines
 
-* Implement mangled characters test.
+* Optimize zero distance directional movements.
 
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-r764 | anrdaemon | 2018-03-14 01:24:28 +0300 (Wed, 14 Mar 2018) | 2 lines
+r793 | anrdaemon | 2018-04-04 21:58:30 +0300 (Wed, 04 Apr 2018) | 4 lines
 
-* Use more common host names.
+* Unify property access pattern across the class.
+  Only directly access property storage, when you actually mean it.
+  In all other cases, use magic to retrieve value of the property.
 
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-r763 | anrdaemon | 2018-03-14 00:50:47 +0300 (Wed, 14 Mar 2018) | 2 lines
+r792 | anrdaemon | 2018-04-04 19:41:30 +0300 (Wed, 04 Apr 2018) | 2 lines
 
-+ Use dedicated normalization of parts array.
++ Refactored Coordinate3D into a generic Point class.
 
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-r762 | anrdaemon | 2018-03-14 00:19:16 +0300 (Wed, 14 Mar 2018) | 4 lines
+r791 | anrdaemon | 2018-04-04 02:09:41 +0300 (Wed, 04 Apr 2018) | 5 lines
 
-* Split autoload.
-* Tweak tests semantics.
-* Put a note about parameter names mangling for Net\Url.
-
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-r741 | anrdaemon | 2018-03-07 02:43:15 +0300 (Wed, 07 Mar 2018) | 2 lines
-
-* Tweak CodeStyle.
-
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-r740 | anrdaemon | 2018-03-04 02:50:24 +0300 (Sun, 04 Mar 2018) | 3 lines
-
-* Hard bind classloader function calls to root namespace.
-- Remove unnecessary stuff from classloader.
-
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-r738 | anrdaemon | 2018-03-03 22:03:36 +0300 (Sat, 03 Mar 2018) | 3 lines
-
-= Move code to subdirectory.
-+ Add some functional tests.
-
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-r737 | anrdaemon | 2018-03-03 21:50:26 +0300 (Sat, 03 Mar 2018) | 3 lines
-
-+ Explicitly create empty object from empty string URL.
-* Lighten up creation process overall.
-
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-r736 | anrdaemon | 2018-03-03 21:14:52 +0300 (Sat, 03 Mar 2018) | 2 lines
-
-* Lighten up Url::setParts() logic.
-
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-r735 | anrdaemon | 2018-03-03 21:01:46 +0300 (Sat, 03 Mar 2018) | 2 lines
-
-* Wrap parse_str and parse_url into usable methods.
-
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-r734 | anrdaemon | 2018-03-03 20:30:12 +0300 (Sat, 03 Mar 2018) | 3 lines
-
-- Remove port type conversion from Url::parse()
-  Url::setParts() already handles it.
-
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-r733 | anrdaemon | 2018-03-03 20:25:24 +0300 (Sat, 03 Mar 2018) | 2 lines
-
-* Normalize internal wrappers naming.
-
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-r727 | anrdaemon | 2018-02-26 17:17:00 +0300 (Mon, 26 Feb 2018) | 2 lines
-
-* Actually universally stackable classloader.
-
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-r709 | anrdaemon | 2017-11-28 22:10:42 +0300 (Tue, 28 Nov 2017) | 2 lines
-
-+ Cache Url::__toString() representation.
-
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-r708 | anrdaemon | 2017-11-28 22:09:53 +0300 (Tue, 28 Nov 2017) | 2 lines
-
-* Explicitly declare methods visibility.
+* Set the groundwork for further development of Point class.
+* Drop redundant capabilities.
+* Make class immutable.
+* Add degrees variant of fromPolar() constructor.
 
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src/Math/GSeq.php

@@ -0,0 +1,113 @@
+<?php
+
+namespace AnrDaemon\Math;
+
+/** Geometric sequence class
+*
+* General usage idea is that you create a new sequence using either base and
+* multiplier, or multiplier, number of elements and a known sum of them.
+*
+* Then you can seek/iterate them as needed, or retrieve specific element via
+* simple function call.
+*/
+class GSeq
+implements \SeekableIterator
+{
+  protected $b, $q, $n;
+
+  protected static function ensureValid($n, $message = null)
+  {
+    if($n < 1 || !is_int($n))
+      throw new \OutOfBoundsException($message ?: 'Sequence number should be integer starting with 1.');
+  }
+
+  /** Create new geometric sequence...
+  *
+  * [1] create($b, $q)
+  *       - from base and multiplier;
+  * [2] create($sum, $q, $n)
+  *       - from sum, multiplier and number of elements.
+  */
+  public static function create($b, $q, $n = 1)
+  {
+    if($n == 1)
+      return new static($b, $q);
+
+    static::ensureValid($n, "Amount of elements must be an integer number bigger than zero.");
+
+    return new static($b * (1 - $q) / (1 - pow($q, $n)), $q);
+  }
+
+  /** Calculate sum of N consequent characters.
+  *
+  * Either N first, or N after first M.
+  *
+  * @param int $n number of elements to sum up
+  * @param ?int $m number of elements to skip
+  * @return float the sum of elements
+  */
+  public function sum($n, $m = 0)
+  {
+    if($m > 0)
+      return $this->sum($n+$m) - $this->sum($m);
+
+    static::ensureValid($n);
+
+    return $this->b * (1 - pow($this->q, $n)) / (1 - $this->q);
+  }
+
+// Magic!
+
+  private function __construct($b, $q)
+  {
+    $this->b = $b;
+    $this->q = $q;
+    $this->n = 1;
+  }
+
+  public function __invoke($n)
+  {
+    if($n == 1)
+      return $this->b;
+
+    static::ensureValid($n);
+
+    return $this->b * pow($this->q, (int)$n - 1);
+  }
+
+// SeekableIterator
+
+  public function seek($n)
+  {
+    static::ensureValid($n);
+
+    $this->n = (int)$n;
+  }
+
+// Iterator
+
+  public function valid()
+  {
+    return $this->n > 0;
+  }
+
+  public function current()
+  {
+    return $this->__invoke($this->n);
+  }
+
+  public function key()
+  {
+    return $this->n;
+  }
+
+  public function next()
+  {
+    $this->n++;
+  }
+
+  public function rewind()
+  {
+    $this->seek(1);
+  }
+}