0.1.3 SparseMatrix

libraries/SparseMatrix/README.md

@@ -88,6 +88,9 @@ Returns false if the internal store is full, true otherwise.
 If needed a new internal element is created. 
 If the sum is zero, the element is removed from the internal store.
 Returns false if the internal store is full, true otherwise.
+- **void  boundingBox(uint8_t &minX, uint8_t &maxX, uint8_t &minY, uint8_t &maxY)** 
+Returns the bounding box in which all values != 0 are located.
+This can be useful for printing or processing the non zero elements.
 
 
 ## Future
@@ -101,14 +104,19 @@ Returns false if the internal store is full, true otherwise.
 - investigate performance optimizations
   - sort
   - linked list, tree, hashing?
-- can **set()** and **add()** be merged?
 
 
 #### Functions
 
 - walk through the elements?
-  - first() -> next();  optional last() -> prev().
-  
+  - in storage order.
+  - bool first(uint8_t &x, uint8_t &y, float &value);
+  - bool next(uint8_t &x, uint8_t &y, float &value);
+  - bool prev(uint8_t &x, uint8_t &y, float &value);
+  - bool last(uint8_t &x, uint8_t &y, float &value);
+  - returns false if there is no element anymore
+  - if count = 0 or current == -1 or end of list.
+
 
 #### won't
 

libraries/SparseMatrix/SparseMatrix.cpp

@@ -1,7 +1,7 @@
 //
 //    FILE: SparseMatrix.cpp
 //  AUTHOR: Rob Tillaart
-// VERSION: 0.1.2
+// VERSION: 0.1.3
 //    DATE: 2022-07-12
 // PURPOSE: Arduino library for sparse matrices
 //     URL: https://github.com/RobTillaart/SparseMatrix
@@ -14,6 +14,9 @@
 //  0.1.2  2022-07-14  increase size to uint16_t
 //                     add SPARSEMATRIX_MAX_SIZE
 //                     improve documentation
+//  0.1.3  2022-07-16  add boundingBox(...)
+//                     fix #4 set() add()
+
 
 
 #include "SparseMatrix.h"
@@ -80,33 +83,13 @@ bool SparseMatrix::set(uint8_t x, uint8_t y, float value)
   //  existing element
   if (pos > -1)
   {
-    if (value != 0.0)
-    {
-      _value[pos] = value;
-    }
-    else
-    {
-      _count--;
-      //  move last element
-      //  efficiency is not a requirement yet.
-      if (_count > 0)
-      {
-        _x[pos]     = _x[_count];
-        _y[pos]     = _y[_count];
-        _value[pos] = _value[_count];
-      }
-    }
+    _value[pos] = value;
+    if (_value[pos] == 0.0) removeElement(pos);
     return true;
   }
 
   //  does not exist => new element ?
-  if (value == 0) return true;
-  if (_count >= _size) return false;
-  _x[_count]     = x;
-  _y[_count]     = y;
-  _value[_count] = value;
-  _count++;
-  return true;
+  return newElement(x, y, value);
 }
 
 
@@ -117,29 +100,12 @@ bool SparseMatrix::add(uint8_t x, uint8_t y, float value)
   if (pos > -1)
   {
     _value[pos] += value;
-    if (_value[pos] == 0.0)
-    {
-      _count--;
-      //  move last element
-      //  efficiency is not a requirement yet.
-      if (_count > 0)
-      {
-        _x[pos]     = _x[_count];
-        _y[pos]     = _y[_count];
-        _value[pos] = _value[_count];
-      }
-    }
+    if (_value[pos] == 0.0) removeElement(pos);
     return true;
   }
 
   //  does not exist => new element ?
-  if (value == 0) return true;
-  if (_count >= _size) return false;
-  _x[_count]     = x;
-  _y[_count]     = y;
-  _value[_count] = value;
-  _count++;
-  return true;
+  return newElement(x, y, value);
 }
 
 
@@ -154,6 +120,24 @@ float SparseMatrix::get(uint8_t x, uint8_t y)
 }
 
 
+void SparseMatrix::boundingBox(uint8_t &minX, uint8_t &maxX, uint8_t &minY, uint8_t &maxY)
+{
+  uint8_t _minx = 255, _maxx = 0,
+          _miny = 255, _maxy = 0;
+  for (uint16_t i = 0; i < _count; i++)
+  {
+    if (_x[i] < _minx) _minx = _x[i];
+    if (_x[i] > _maxx) _maxx = _x[i];
+    if (_y[i] < _miny) _miny = _y[i];
+    if (_y[i] > _maxy) _maxy = _y[i];
+  }
+  minX = _minx;
+  maxX = _maxx;
+  minY = _miny;
+  maxY = _maxy;
+}
+
+
 //////////////////////////////////////////////////////
 //
 //  PRIVATE
@@ -172,6 +156,29 @@ int32_t SparseMatrix::findPos(uint8_t x, uint8_t y)
 }
 
 
+void SparseMatrix::removeElement(uint16_t pos)
+{
+  _count--;
+  //  move last element
+  //  efficiency (keep sorted) is no requirement.
+  if (pos == _count) return;
+  _x[pos]     = _x[_count];
+  _y[pos]     = _y[_count];
+  _value[pos] = _value[_count];
+}
+
+
+bool SparseMatrix::newElement(uint8_t x, uint8_t y, float value)
+{
+  if (value == 0.0) return true;
+  if (_count >= _size) return false;
+  _x[_count]     = x;
+  _y[_count]     = y;
+  _value[_count] = value;
+  _count++;
+  return true;
+}
+
 
 // -- END OF FILE --
 

libraries/SparseMatrix/SparseMatrix.h

@@ -2,7 +2,7 @@
 //
 //    FILE: SparseMatrix.h
 //  AUTHOR: Rob Tillaart
-// VERSION: 0.1.2
+// VERSION: 0.1.3
 //    DATE: 2022-07-12
 // PURPOSE: Arduino library for sparse matrices
 //     URL: https://github.com/RobTillaart/SparseMatrix
@@ -11,7 +11,7 @@
 
 #include "Arduino.h"
 
-#define SPARSEMATRIX_LIB_VERSION        (F("0.1.2"))
+#define SPARSEMATRIX_LIB_VERSION        (F("0.1.3"))
 
 #ifndef SPARSEMATRIX_MAX_SIZE
 #define SPARSEMATRIX_MAX_SIZE           1000
@@ -38,6 +38,10 @@ public:
   float    get(uint8_t x, uint8_t y);
 
 
+  //  returns four sides between all values != 0 are located.
+  void     boundingBox(uint8_t &minX, uint8_t &maxX, uint8_t &minY, uint8_t &maxY);
+
+
 private:
   uint16_t  _size   = 0;
   uint16_t  _count  = 0;
@@ -49,6 +53,12 @@ private:
   //  returns index of x, y if in set
   //  otherwise -1
   int32_t findPos(uint8_t x, uint8_t y);
+
+  //  removes element at pos (from findPos)
+  //  pre: count > 0
+  void    removeElement(uint16_t pos);
+  //  creates a new element if value != 0 and if there is room
+  bool    newElement(uint8_t x, uint8_t y, float value);
 };
 
 

libraries/SparseMatrix/examples/sparse_matrix_boundingBox/sparse_matrix_boundingBox.ino

@@ -0,0 +1,79 @@
+//
+//    FILE: sparse_matrix_boundingBox.ino
+//  AUTHOR: Rob Tillaart
+// PURPOSE: demo
+//     URL: https://github.com/RobTillaart/SparseMatrix
+
+
+#include  "SparseMatrix.h"
+
+
+SparseMatrix sm(10);
+
+
+void setup()
+{
+  Serial.begin(115200);
+  Serial.println();
+  Serial.println(__FILE__);
+  Serial.println();
+
+  //  10 x 10 matrix - 6 random elements in the middle
+  for (int i = 0; i < 6; i++)
+  {
+    uint8_t x = random(5) + 3;
+    uint8_t y = random(5) + 3;
+    sm.set(x, y, random(37));
+  }
+  dump(10, 10);
+
+  uint8_t minX, maxX, minY, maxY;
+  sm.boundingBox(minX, maxX, minY, maxY);
+
+  Serial.println("\tBounding Box");
+  Serial.print("\t");
+  Serial.print(minX);
+  Serial.print("\t");
+  Serial.print(maxX);
+  Serial.print("\t");
+  Serial.print(minY);
+  Serial.print("\t");
+  Serial.print(maxY);
+  Serial.println();
+}
+
+
+void loop()
+{
+}
+
+
+void dump(uint8_t sx, uint8_t sy)
+{
+  Serial.println();
+  Serial.print("DUMP\t");
+
+  Serial.print(sm.size());
+  Serial.print("\t");
+  Serial.print(sm.count());
+  Serial.print("\t");
+
+  Serial.print(sx);
+  Serial.print("x");
+  Serial.print(sy);
+  Serial.print("\t");
+  Serial.println(sm.sum());
+  for (int y = 0; y < sy; y++)
+  {
+    for (int x = 0; x < sx; x++)
+    {
+      Serial.print(sm.get(x, y));
+      Serial.print('\t');
+    }
+    Serial.println();
+  }
+  Serial.println();
+}
+
+
+//  -- END OF FILE --

libraries/SparseMatrix/examples/sparse_matrix_performance/performance_0.1.3.txt

@@ -0,0 +1,15 @@
+sparse_matrix_performance.ino
+
+0.1.3
+20
+0
+
+set 20x :	428
+redo 20x :	380
+full 20x :	528
+add 20x :	452
+get 20x :	244
+9.00
+sum 20x :	164
+clr 20x :	4
+

libraries/SparseMatrix/library.json

@@ -15,7 +15,7 @@
     "type": "git",
     "url": "https://github.com/RobTillaart/SparseMatrix.git"
   },
-  "version": "0.1.2",
+  "version": "0.1.3",
   "license": "MIT",
   "frameworks": "arduino",
   "platforms": "*",

libraries/SparseMatrix/library.properties

@@ -1,5 +1,5 @@
 name=SparseMatrix
-version=0.1.2
+version=0.1.3
 author=Rob Tillaart <rob.tillaart@gmail.com>
 maintainer=Rob Tillaart <rob.tillaart@gmail.com>
 sentence=Arduino library for sparse matrices.

libraries/SparseMatrix/test/unit_test_001.cpp

@@ -119,6 +119,26 @@ unittest(test_add)
 }
 
 
+unittest(test_boundix_box)
+{
+  SparseMatrix sm(10);
+  //  10 x 10 matrix - 6 random elements in the middle
+  for (int i = 0; i < 6; i++)
+  {
+    uint8_t x = random(5) + 3;
+    uint8_t y = random(5) + 3;
+    sm.set(x, y, random(37));
+  }
+  //  random generator does not work
+  //  assertEqual(6, sm.count());
+  assertEqual(1, sm.count());
+
+  uint8_t minX, maxX, minY, maxY;
+  sm.boundingBox(minX, maxX, minY, maxY);
+  fprintf(stderr, "%d\t%d\t%d\t%d\n", minX, maxX, minY, maxY);
+}
+
+
 unittest_main()