+ distanceTable initial version

+ refactor
+ testsketch

libraries/DistanceTable/DistanceTable.cpp

@@ -0,0 +1,83 @@
+//
+//    FILE: DistanceTable.cpp
+//  AUTHOR: Rob Tillaart
+// VERSION: 0.1.01
+// PURPOSE: library for a memory efficient DistanceTable for Arduino
+//     URL:
+//
+// Released to the public domain
+//
+
+// 0.1.00 - initial version
+// 0.1.01 - refactor
+
+#include "DistanceTable.h"
+
+DistanceTable::DistanceTable(uint8_t size)
+{
+    _size = size;
+    uint16_t s = size * (size-1)/2;
+    _distanceTable = (double*) malloc(s * sizeof(double));
+    if (_distanceTable == NULL) _size = 0;
+}
+
+DistanceTable::~DistanceTable()
+{
+    if (_distanceTable != NULL) free(_distanceTable);
+}
+
+void DistanceTable::clear()
+{
+    uint16_t s = _size * (_size-1)/2;
+    for (uint16_t index = 0; index < s; index++)
+    {
+        _distanceTable[index] = 0;
+    }
+};
+
+void DistanceTable::set(uint8_t x, uint8_t y, double value )
+{
+    if ( x >= _size || y >= _size) return;
+    if ( x == y ) return;
+    // need swap?
+    if ( x < y ) 
+    {
+        uint8_t t = x; x = y; y = t;
+    }
+    uint16_t index = x;
+    index = index * (index-1)/2 + y;
+    _distanceTable[index] = value;
+};
+
+double DistanceTable::get(uint8_t x, uint8_t y)
+{
+    if ( x >= _size || y >= _size) return -1;
+    if ( x == y ) return 0;
+    // need swap?
+    if ( x < y ) 
+    {
+        uint8_t t = x; x = y; y = t;
+    }
+    uint16_t index = x;
+    index = index * (index-1)/2 + y;
+    return _distanceTable[index];
+};
+
+
+void DistanceTable::dump()
+{
+    uint16_t index = 0;
+    for (uint16_t i = 0; i < _size-1; i++)
+    {
+        for (uint16_t j = 0; j <= i; j++)
+        {
+            Serial.print(_distanceTable[index++]);
+            Serial.print("\t");
+        }
+        Serial.println();
+    }     
+    Serial.println();
+};
+
+
+// --- END OF FILE ---

libraries/DistanceTable/DistanceTable.h

@@ -0,0 +1,36 @@
+//
+//    FILE: DistanceTable.h
+//  AUTHOR: Rob Tillaart
+// VERSION: 0.1.01
+// PURPOSE: memory efficient DistanceTable for Arduino
+//     URL: 
+//
+// Released to the public domain
+//
+
+#ifndef DistanceTable_h
+#define DistanceTable_h
+
+#include "Arduino.h"
+
+#define DISTANCETABLE_LIB_VERSION "0.1.01"
+
+class DistanceTable
+{
+public:
+    DistanceTable(uint8_t);
+    ~DistanceTable();
+
+    void clear();
+    void set(uint8_t x, uint8_t y, double value );
+    double get(uint8_t x, uint8_t y);
+    void dump();
+
+protected:
+    int _error;
+    uint8_t _size;
+    double * _distanceTable;
+};
+
+#endif
+// --- END OF FILE ---

libraries/DistanceTable/example/distanceTable/distanceTable.ino

@@ -0,0 +1,95 @@
+//
+//    FILE: distanceTable.ino
+//  AUTHOR: Rob Tillaart
+// VERSION: 0.1.00
+// PURPOSE: demo of memory efficient distance table class
+//    DATE: 2015-06-18
+//     URL: 
+//
+// Released to the public domain
+//
+
+#include "DistanceTable.h"
+
+uint32_t freeRam()
+{
+  extern int __heap_start, *__brkval;
+  int v;
+  return (uint32_t) &v - (__brkval == 0 ? (uint32_t) &__heap_start : (uint32_t) __brkval);
+};
+
+DistanceTable dt(20);
+
+uint32_t start;
+uint32_t stop;
+
+void setup()
+{
+  Serial.begin(115200);
+  Serial.print("DistanceTable: ");
+  Serial.println(DISTANCETABLE_LIB_VERSION);
+  Serial.println("DistanceTable test 20x20: ");
+
+  Serial.print("clear:\t");
+  start = micros();
+  dt.clear();
+  stop = micros();
+  Serial.println(stop - start);
+
+
+  Serial.print("set:\t");
+  start = micros();
+  for (int i = 0; i < 20; i++)
+  {
+    for (int j = 0; j < 20; j++)
+    {
+      dt.set(i, j, i * j);
+    }
+  }
+  stop = micros();
+  Serial.println(stop - start);
+
+
+  Serial.print("get:\t");
+  int count = 0;
+  start = micros();
+  for (int i = 0; i < 20; i++)
+  {
+    for (int j = 0; j < 20; j++)
+    {
+      if ( dt.get(i, j) < 0.5 ) count++;
+    }
+  }
+  stop = micros();
+  Serial.println(stop - start);
+  Serial.print("count:\t");
+  Serial.println(count);
+
+  Serial.print("ram:\t");
+  Serial.println(freeRam());
+
+  Serial.println();
+  Serial.println("dump:\t");
+  for (int i = 0; i < 20; i++)
+  {
+    for (int j = 0; j < 20; j++)
+    {
+      Serial.print( dt.get(i, j), 1);
+      Serial.print("\t");
+    }
+    Serial.println();
+  }
+
+  Serial.println();
+  Serial.println("dump:\t");
+  dt.dump();
+
+  Serial.println();
+  Serial.println("done...");
+}
+
+void loop()
+{
+}
+
+