aggregation working

Coursework/buffer.h

@@ -4,7 +4,7 @@
 #include "util.h"
 
 void 
-aggregateBuffer(float bufferIn[], int lengthIn, float bufferOut[], int lengthOut, int groupSize)
+aggregateBuffer(float *bufferIn, int lengthIn, float *bufferOut, int lengthOut, int groupSize)
 {
     int requiredGroups = ceil((float)lengthIn/groupSize);
     int finalGroupSize = (lengthIn % groupSize) * groupSize;
@@ -12,45 +12,55 @@ aggregateBuffer(float bufferIn[], int lengthIn, float bufferOut[], int lengthOut
     if(requiredGroups > lengthOut)
     {
         putFloat((float)lengthIn/groupSize);
-        printf(" length out buffer required, %i provided", lengthOut);
+        printf(" length out buffer required, %i provided\n", lengthOut);
         return;
     }
 
     int g;// for group number
+    float *inputPtr = bufferIn;
+    float *outputPtr = bufferOut;
     for(g = 0; g < requiredGroups; g++)
     {        
         int length = groupSize;
         if(g == requiredGroups - 1 && finalGroupSize != 0) length = finalGroupSize;
-        bufferOut[g] = calculateMean(&bufferIn + (g*groupSize), length);
+        
+        *outputPtr = calculateMean(inputPtr, length);
+        
+        inputPtr += length;
+        outputPtr++;
     }
 }
 
 void 
-clearBuffer(float buffer[], int length)
+clearBuffer(float *buffer, int length)
 {
     if(length > 0)
     {
         int i;
+        float *bufferPtr = buffer;
         for(i = 0; i < length; i++)
         {
-            buffer[i] = 0.0;
+            *bufferPtr = 0.0;
+            bufferPtr++;
         }
     }
 }
 
 void 
-printBuffer(float buffer[], int length)
+printBuffer(float *buffer, int length)
 {
     putchar('[');
 
     if(length > 0)
     {
         int i;
+        float *ptr = buffer;
         for(i = 0; i < length; i++)
         {
             if(i > 0) printf(", ");
 
-            putFloat(buffer[i]);
+            putFloat(*ptr);
+            ptr++;
         }
     }    
 

Coursework/coursework.c

@@ -1,8 +1,8 @@
 #define READING_INTERVAL 3 //in Hz
-#define BUFFER_SIZE 5
+#define BUFFER_SIZE 12 // length of buffer to populate
 
-#define SD_THRESHOLD 3
-#define AGGREGATION_GROUP_SIZE 4
+#define SD_THRESHOLD 0 // whether to aggregate or flatten
+#define AGGREGATION_GROUP_SIZE 4 // group size to aggregate (4 in spec)
 
 #include "contiki.h"
 #include "dev/light-sensor.h"
@@ -13,7 +13,9 @@
 #include "math.h"
 #include "buffer.h"
 
-// get float from light sensor including T function
+//text to uncomment and make the sim reload new source
+
+// get float from light sensor including transfer function
 float
 getLight(void)
 {
@@ -27,7 +29,7 @@ getLight(void)
 
 // Process final buffer following aggregation
 void
-handleFinalBuffer(float buffer[], int length)
+handleFinalBuffer(float *buffer, int length)
 {
     printf("Final buffer output: ");
     printBuffer(buffer, length);putchar('\n');putchar('\n');
@@ -35,30 +37,31 @@ handleFinalBuffer(float buffer[], int length)
 
 // Buffer filled with readings, process and aggregate
 void
-handleBufferRotation(float buffer[], int length)
+handleBufferRotation(float *buffer, int length)
 {
     printf("Buffer full, aggregating\n\n");
-    float aggregated[BUFFER_SIZE];
 
-    Stats sd = calculateStdDev(buffer, length);
+    Stats sd = calculateStdDev(buffer, length); // GET BUFFER STATISTICS
     if(sd.std > SD_THRESHOLD)
     {// buffer length by 4
         printf("Significant STD: ");
         putFloat(sd.std);
         printf(", compressing buffer\n");
 
-        float outBuffer[BUFFER_SIZE];
-        int outLength = ceil((float)length/AGGREGATION_GROUP_SIZE);
-        aggregateBuffer(buffer, length, outBuffer, outLength, AGGREGATION_GROUP_SIZE);
+        float outBuffer[BUFFER_SIZE]; // CREATE OUTPUT BUFFER
+        clearBuffer(&outBuffer, BUFFER_SIZE);
         
-        handleFinalBuffer(outBuffer, outLength);
+        int outLength = ceil((float)length/AGGREGATION_GROUP_SIZE); // CALCULATE NUMBER OF OUTPUT ELEMENTS
+        aggregateBuffer(buffer, length, &outBuffer, outLength, AGGREGATION_GROUP_SIZE);
+    
+        handleFinalBuffer(&outBuffer, outLength); // PASS FINAL BUFFER
     }else
     {// buffer length to 1
         printf("Insignificant STD: ");
         putFloat(sd.std);
         printf(", squashing buffer\n");
 
-        handleFinalBuffer(&sd.mean, 1);
+        handleFinalBuffer(&sd.mean, 1); // PASS FINAL BUFFER
     }
     clearBuffer(buffer, length);
 }
@@ -78,8 +81,8 @@ PROCESS_THREAD(aggregator_process, ev, data)
     etimer_set(&timer, CLOCK_SECOND/READING_INTERVAL);
     SENSORS_ACTIVATE(light_sensor);
     
-    clearBuffer(buffer, BUFFER_SIZE);
-    printBuffer(buffer, BUFFER_SIZE);putchar('\n');putchar('\n');
+    clearBuffer(&buffer, BUFFER_SIZE);
+    printBuffer(&buffer, BUFFER_SIZE);putchar('\n');putchar('\n');
     /*END INIT*/
     
     static int counter = 0;
@@ -87,15 +90,15 @@ PROCESS_THREAD(aggregator_process, ev, data)
     {
         PROCESS_WAIT_EVENT_UNTIL(ev=PROCESS_EVENT_TIMER);
         
-        float light_lx = getLight();
+        float light_lx = getLight(); // GET
 
-        buffer[counter] = light_lx;
-        printBuffer(buffer, BUFFER_SIZE);putchar('\n');
+        buffer[counter] = light_lx; // STORE
+        printBuffer(&buffer, BUFFER_SIZE);putchar('\n'); // DISPLAY
         
         counter++;
-        if(counter == BUFFER_SIZE)
+        if(counter == BUFFER_SIZE) // CHECK WHETHER FULL
         {
-            handleBufferRotation(buffer, BUFFER_SIZE);
+            handleBufferRotation(buffer, BUFFER_SIZE); // PASS OUT IF FULL
             counter = 0;
         }