From 7e20e4eb199a82bec69917e066b5e39ef2888db1 Mon Sep 17 00:00:00 2001
From: Frederik Beimgraben <frederik@beimgraben.net>
Date: Sat, 11 Jan 2025 19:40:49 +0100
Subject: [PATCH] Add Ex. 2 and 3; FIXMEs remain open

---
 MMS24-25.c | 165 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 165 insertions(+)

diff --git a/MMS24-25.c b/MMS24-25.c
index c924e69..c589041 100644
--- a/MMS24-25.c
+++ b/MMS24-25.c
@@ -331,3 +331,168 @@ void deleteSignal(MMSignal *pmmsIn) {
 // #endregion
 
 // #region Aufgabe 2
+double calculateArea(double *pdIn, int iLen) {
+    double area = 0;
+
+    // #FIXME: Which one should we use according to the task?
+    for (int i = 0; i < iLen-1; i++) {
+        area += (pdIn[i] + pdIn[i+1]) / 2;
+    }
+
+    return area;
+}
+
+double calculateMean(double *pdIn, int iLen) {
+    double mean = 0;
+
+    for (int i = 0; i < iLen; i++) {
+        mean += pdIn[i];
+    }
+
+    return mean / iLen;
+}
+
+double calculateStddev(double *pdIn, int iLen) {
+    double mean = calculateMean(pdIn, iLen);
+    double stdDev = 0;
+
+    for (int i = 0; i < iLen; i++) {
+        stdDev += pow(pdIn[i] - mean, 2);
+    }
+
+    return sqrt(stdDev / iLen);
+}
+
+Extrema *initExtrema(double *pdIn, int iLen) {
+    Extrema *extrema = (Extrema*) malloc(sizeof(Extrema));
+    if (extrema == NULL)
+        _error("initExtrema: Failed to allocate memory for extrema\n");
+
+    extrema->pexLocalMax = (LocalExtrema*) malloc(sizeof(LocalExtrema));
+    if (extrema->pexLocalMax == NULL)
+        _error("initExtrema: Failed to allocate memory for extrema->pexLocalMax\n");
+
+    extrema->pexLocalMin = (LocalExtrema*) malloc(sizeof(LocalExtrema));
+    if (extrema->pexLocalMin == NULL)
+        _error("initExtrema: Failed to allocate memory for extrema->pexLocalMin\n");
+
+    extrema->pexLocalMax->piLocalExtremaPos = (int*) malloc(sizeof(int) *iLen);
+    if (extrema->pexLocalMax->piLocalExtremaPos == NULL)
+        _error("initExtrema: Failed to allocate memory for extrema->pexLocalMax->piLocalExtremaPos\n");
+
+    extrema->pexLocalMin->piLocalExtremaPos = (int*) malloc(sizeof(int) *iLen);
+    if (extrema->pexLocalMin->piLocalExtremaPos == NULL)
+        _error("initExtrema: Failed to allocate memory for extrema->pexLocalMin->piLocalExtremaPos\n");
+
+    extrema->iGlobalMaxPos = 0;
+    extrema->iGlobalMinPos = 0;
+
+    return extrema;
+}
+
+void deleteExtrema(Extrema *pexIn) {
+    free(pexIn->pexLocalMax->piLocalExtremaPos);
+    free(pexIn->pexLocalMax);
+    free(pexIn->pexLocalMin->piLocalExtremaPos);
+    free(pexIn->pexLocalMin);
+    free(pexIn);
+}
+
+void initMMSignalFeatures(MMSignal *pmmsIn) {
+    pmmsIn->dArea = calculateArea(pmmsIn->pdValues, pmmsIn->iNumValues);
+    pmmsIn->dMean = calculateMean(pmmsIn->pdValues, pmmsIn->iNumValues);
+    pmmsIn->dStdDev = calculateStddev(pmmsIn->pdValues, pmmsIn->iNumValues);
+    pmmsIn->dMedian = calculateMedian(pmmsIn->pdValues, pmmsIn->iNumValues);
+    pmmsIn->pexExtrema = initExtrema(pmmsIn->pdValues, pmmsIn->iNumValues);
+}
+
+Histogram *initHistogram(double *pdIn, int iLen, int iNumBins) {
+    Histogram *histogram = (Histogram*) malloc(sizeof(Histogram));
+    if (histogram == NULL)
+        _error("initHistogram: Failed to allocate memory for histogram\n");
+
+    histogram->dIntervalMin = pdIn[0];
+    histogram->dIntervalMax = pdIn[0];
+    for (int i = 0; i < iLen; i++) {
+        if (pdIn[i] < histogram->dIntervalMin)
+            histogram->dIntervalMin = pdIn[i];
+        if (pdIn[i] > histogram->dIntervalMax)
+            histogram->dIntervalMax = pdIn[i];
+    }
+
+    histogram->dBinWidth = (histogram->dIntervalMax - histogram->dIntervalMin) / iNumBins;
+    histogram->iNumBins = iNumBins;
+
+    histogram->pdBinValues = (double*) malloc(sizeof(double) *iNumBins);
+    if (histogram->pdBinValues == NULL)
+        _error("initHistogram: Failed to allocate memory for histogram->pdBinValues\n");
+
+    for (int i = 0; i < iNumBins; i++) {
+        histogram->pdBinValues[i] = 0;
+    }
+
+    return histogram;
+}
+
+void deleteHistogram(Histogram *phIn) {
+    free(phIn->pdBinValues);
+    free(phIn);
+}
+
+// #FIXME: Check if this checks out
+double calculateEntropy(Histogram *phisIn) {
+    double entropy = 0;
+
+    for (int i = 0; i < phisIn->iNumBins; i++) {
+        if (phisIn->pdBinValues[i] != 0) {
+            entropy += phisIn->pdBinValues[i] * log2(phisIn->pdBinValues[i]);
+        }
+    }
+
+    return -entropy;
+}
+
+// #endregion
+
+// #region Aufgabe 3
+
+MMSignal *convoluteSignals(MMSignal *pmmsInA, MMSignal *pmmsInB) {
+    MMSignal *signal = createSignal();
+
+    if (pmmsInA->iNumValues != pmmsInB->iNumValues)
+        _error("convoluteSignals: Signals must have the same length\n");
+
+    signal->pdValues = (double*) malloc(sizeof(double) *pmmsInA->iNumValues);
+    if (signal->pdValues == NULL)
+        _error("convoluteSignals: Failed to allocate memory for signal->pdValues\n");
+
+    for (int i = 0; i < pmmsInA->iNumValues; i++) {
+        signal->pdValues[i] = pmmsInA->pdValues[i] * pmmsInB->pdValues[i];
+    }
+
+    signal->iNumValues = pmmsInA->iNumValues;
+
+    return signal;
+}
+
+// #FIXME: Check if this checks out
+MMSignal *getPascalLine(int iLinenum) {
+    MMSignal *signal = createSignal();
+
+    signal->pdValues = (double*) malloc(sizeof(double) *iLinenum);
+    if (signal->pdValues == NULL)
+        _error("getPascalLine: Failed to allocate memory for signal->pdValues\n");
+
+    signal->pdValues[0] = 1;
+    signal->pdValues[iLinenum-1] = 1;
+
+    for (int i = 1; i < iLinenum-1; i++) {
+        signal->pdValues[i] = signal->pdValues[i-1] *(iLinenum-i) / i;
+    }
+
+    signal->iNumValues = iLinenum;
+
+    return signal;
+}
+
+// #endregion