add discretizer (utils)

include/puara/utils/discretizer.h

@@ -0,0 +1,43 @@
+#pragma once
+
+template <typename T>
+class ValueMonitor {
+private:
+  T latestValue;
+  bool firstValue; // Flag to track if it's the first value
+
+public:
+  // Constructor
+  ValueMonitor() : firstValue(true) {
+    // Initialize latestValue to a default value.  Important to avoid
+    // undefined behavior on the first comparison.  Using the minimum
+    // value for numeric types is usually a good choice.
+    latestValue = std::numeric_limits<T>::min(); 
+  }
+
+  // Method to update the value and check for difference
+  bool updateAndCheck(const T& newValue) {
+    if (firstValue) {
+      latestValue = newValue;
+      firstValue = false;
+      return true; // It's the first value, so it's technically "different"
+    }
+
+    if (newValue != latestValue) {
+      latestValue = newValue;
+      return true; // Values are different
+    } else {
+      return false; // Values are the same
+    }
+  }
+
+  // Method to get the latest value (const version)
+  const T& getLatestValue() const {
+    return latestValue;
+  }
+
+  // Method to get the latest value (non-const version)
+  T& getLatestValue() {
+    return latestValue;
+  }
+};