5. Вывод гистограммы как изображения в формате SVG

.gitignore

@@ -0,0 +1,3 @@
+/bin
+/obj
+/*.layout

histogram.cpp

@@ -1,10 +1,10 @@
 #include "histogram.h"
+#include "histogram_internal.h"
 #include <vector>
 using namespace std;
 
-static void find_minmax(const vector<double>& numbers, double& min, double& max) {
+void find_minmax(const vector<double>& numbers, double& min, double& max) {
     if (numbers.empty()) return;
-
     min = numbers[0];
     max = numbers[0];
     for (double x : numbers) {

histogram_internal.h

@@ -0,0 +1,8 @@
+#ifndef HISTOGRAM_INTERNAL_H_INCLUDED
+#define HISTOGRAM_INTERNAL_H_INCLUDED
+
+#include <vector>
+
+void find_minmax(const std::vector<double>& numbers, double& min, double& max);
+
+#endif // HISTOGRAM_INTERNAL_H_INCLUDED

lab01.cbp

@@ -32,7 +32,19 @@
 			<Add option="-Wall" />
 			<Add option="-fexceptions" />
 		</Compiler>
+		<Unit filename=".gitignore" />
+		<Unit filename="histogram.cpp" />
+		<Unit filename="histogram.h">
+			<Option target="&lt;{~None~}&gt;" />
+		</Unit>
+		<Unit filename="histogram_internal.h">
+			<Option target="&lt;{~None~}&gt;" />
+		</Unit>
 		<Unit filename="main.cpp" />
+		<Unit filename="text.cpp" />
+		<Unit filename="text.h">
+			<Option target="&lt;{~None~}&gt;" />
+		</Unit>
 		<Extensions>
 			<lib_finder disable_auto="1" />
 		</Extensions>

main.cpp

@@ -2,6 +2,7 @@
 #include <vector>
 #include "histogram.h"
 #include "text.h"
+#include "svg.h"
 using namespace std;
 
 struct Input {
@@ -33,10 +34,37 @@ Input input_data() {
     return in;
 }
 
+void show_histogram_svg(const vector<size_t>& bins) {
+    const auto IMAGE_WIDTH = 400;
+    const auto IMAGE_HEIGHT = 300;
+    const auto TEXT_LEFT = 20;
+    const auto TEXT_BASELINE = 20;
+    const auto TEXT_WIDTH = 50;
+    const auto BIN_HEIGHT = 30;
+    const auto BLOCK_WIDTH = 10;
+
+    svg_begin(IMAGE_WIDTH, IMAGE_HEIGHT);
+
+    size_t max_count = 0;
+    for (size_t count : bins) {
+        if (count > max_count) max_count = count;
+    }
+
+    double top = 0;
+    for (size_t bin : bins) {
+        const double bin_width = (max_count > 0) ?
+            (static_cast<double>(bin) / max_count * (IMAGE_WIDTH - TEXT_WIDTH)) : 0;
+        svg_text(TEXT_LEFT, top + TEXT_BASELINE, to_string(bin));
+        svg_rect(TEXT_WIDTH, top, bin_width, BIN_HEIGHT, "black", "#aaffaa");
+        top += BIN_HEIGHT;
+    }
+
+    svg_end();
+}
+
 int main() {
     auto input = input_data();
     auto bins = make_histogram(input.numbers, input.bin_count);
-    show_histogram_text(bins);
-
+    show_histogram_svg(bins);
     return 0;
 }

svg.cpp

@@ -0,0 +1,26 @@
+#include "svg.h"
+#include <iostream>
+
+using namespace std;
+
+void svg_begin(double width, double height) {
+    cout << "<?xml version='1.0' encoding='UTF-8' ?>\n";
+    cout << "<svg width='" << width << "' height='" << height << "' "
+         << "viewBox='0 0 " << width << " " << height << "' "
+         << "xmlns='http://www.w3.org/2000/svg'>\n";
+}
+
+void svg_end() {
+    cout << "</svg>\n";
+}
+
+void svg_text(double left, double baseline, const std::string& text) {
+    cout << "<text x='" << left << "' y='" << baseline << "'>" << text << "</text>\n";
+}
+
+void svg_rect(double x, double y, double width, double height,
+              const std::string& stroke, const std::string& fill) {
+    cout << "<rect x='" << x << "' y='" << y << "' width='" << width
+         << "' height='" << height << "' stroke='" << stroke
+         << "' fill='" << fill << "' />\n";
+}

svg.h

@@ -0,0 +1,12 @@
+#ifndef SVG_H_INCLUDED
+#define SVG_H_INCLUDED
+
+#include <vector>
+#include <string>
+
+void svg_begin(double width, double height);
+void svg_end();
+void svg_text(double left, double baseline, const std::string& text);
+void svg_rect(double x, double y, double width, double height, const std::string& stroke = "black", const std::string& fill = "black");
+
+#endif // SVG_H_INCLUDED

unittest.cbp

@@ -0,0 +1,38 @@
+<?xml version="1.0" encoding="UTF-8" standalone="yes" ?>
+<CodeBlocks_project_file>
+	<FileVersion major="1" minor="6" />
+	<Project>
+		<Option title="unittest" />
+		<Option pch_mode="2" />
+		<Option compiler="gcc" />
+		<Build>
+			<Target title="Debug">
+				<Option output="bin/Debug/unittest" prefix_auto="1" extension_auto="1" />
+				<Option object_output="obj/Debug/" />
+				<Option type="1" />
+				<Option compiler="gcc" />
+				<Compiler>
+					<Add option="-g" />
+				</Compiler>
+			</Target>
+			<Target title="Release">
+				<Option output="bin/Release/unittest" prefix_auto="1" extension_auto="1" />
+				<Option object_output="obj/Release/" />
+				<Option type="1" />
+				<Option compiler="gcc" />
+				<Compiler>
+					<Add option="-O2" />
+				</Compiler>
+				<Linker>
+					<Add option="-s" />
+				</Linker>
+			</Target>
+		</Build>
+		<Compiler>
+			<Add option="-Wall" />
+		</Compiler>
+		<Extensions>
+			<lib_finder disable_auto="1" />
+		</Extensions>
+	</Project>
+</CodeBlocks_project_file>

unittest.cpp

@@ -0,0 +1,36 @@
+#define DOCTEST_CONFIG_NO_MULTITHREADING
+#define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
+#include "doctest.h"
+#include "histogram_internal.h"
+
+TEST_CASE("distinct positive numbers") {
+    double min = 0;
+    double max = 0;
+    find_minmax({1, 2}, min, max);
+    CHECK(min == 1);
+    CHECK(max == 2);
+}
+
+TEST_CASE("identical numbers") {
+    double min = 0;
+    double max = 0;
+    find_minmax({5, 5}, min, max);
+    CHECK(min == 5);
+    CHECK(max == 5);
+}
+
+TEST_CASE("single element") {
+    double min = 0;
+    double max = 0;
+    find_minmax({-3}, min, max);
+    CHECK(min == -3);
+    CHECK(max == -3);
+}
+
+TEST_CASE("empty vector") {
+    double min = 0;
+    double max = 0;
+    find_minmax({}, min, max);
+    CHECK(min == 0);
+    CHECK(max == 0);
+}