From 13bce3044591289de476fd97dfb9cf2c8b25b4a9 Mon Sep 17 00:00:00 2001
From: "Sasha (KobzevAV)" <KobzevAV@mpei.ru>
Date: Sun, 23 Apr 2023 23:03:14 +0300
Subject: [PATCH] header: histogram

---
 histogram.cpp | 37 +++++++++++++++++++++++++++++++++++++
 histogram.h   |  8 ++++++++
 2 files changed, 45 insertions(+)
 create mode 100644 histogram.cpp
 create mode 100644 histogram.h

diff --git a/histogram.cpp b/histogram.cpp
new file mode 100644
index 0000000..b3defde
--- /dev/null
+++ b/histogram.cpp
@@ -0,0 +1,37 @@
+#include "histogram.h"
+void
+find_minmax(const std::vector<double>& numbers, double& min, double& max){
+    min = numbers[0];
+    max = numbers[0];
+    for (double x: numbers){
+        if (min > x){
+            min = x;
+        }
+        if (max < x){
+            max = x;
+        }
+    }
+}
+
+std::vector<size_t>
+make_histogram(const std::vector<double>& numbers, size_t bin_count){
+    double min, max;
+    std::vector <size_t> bins(bin_count);
+    find_minmax(numbers, min, max);
+    double diff = (max - min) / bin_count;
+    for (double x: numbers){
+        bool found = false;
+        for (size_t j = 0;(j < bin_count - 1) && !found; j++){
+            auto lo = min + j * diff;
+            auto hi = min + (j + 1) * diff;
+            if ((lo <= x) && (hi > x)){
+                bins[j]++;
+                found = true;
+            }
+        }
+        if(!found){
+            bins[bin_count - 1]++;
+        }
+    }
+    return bins;
+}
diff --git a/histogram.h b/histogram.h
new file mode 100644
index 0000000..11954ba
--- /dev/null
+++ b/histogram.h
@@ -0,0 +1,8 @@
+#ifndef HISTOGRAM_H_INCLUDED
+#define HISTOGRAM_H_INCLUDED
+#include <vector>
+
+
+std::vector<size_t>
+make_histogram(const std::vector<double>& numbers, size_t bin_count);
+#endif // HISTOGRAM_H_INCLUDED