Merge pull request lava#1 from tkphd/imshow

rebase imshow to origin/master

Author: alexdewar

Makefile

@@ -1,10 +1,10 @@
-examples: minimal basic modern animation nonblock xkcd quiver
+examples: minimal basic modern animation nonblock xkcd quiver bar surface fill_inbetween fill update
 
 minimal: examples/minimal.cpp matplotlibcpp.h
 	cd examples && g++ -DWITHOUT_NUMPY minimal.cpp -I/usr/include/python2.7 -lpython2.7 -o minimal -std=c++11
 
 basic: examples/basic.cpp matplotlibcpp.h
-	cd examples && g++ basic.cpp -I/usr/include/python2.7 -lpython2.7 -o basic
+	cd examples && g++ basic.cpp -I/usr/include/python2.7 -lpython2.7 -o basic -std=c++11
 
 modern: examples/modern.cpp matplotlibcpp.h
 	cd examples && g++ modern.cpp -I/usr/include/python2.7 -lpython2.7 -o modern -std=c++11
@@ -21,5 +21,20 @@ quiver: examples/quiver.cpp matplotlibcpp.h
 xkcd: examples/xkcd.cpp matplotlibcpp.h
 	cd examples && g++ xkcd.cpp -I/usr/include/python2.7 -lpython2.7 -o xkcd -std=c++11
 
+bar: examples/bar.cpp matplotlibcpp.h
+	cd examples && g++ bar.cpp -I/usr/include/python2.7 -lpython2.7 -o bar -std=c++11
+
+surface: examples/surface.cpp matplotlibcpp.h
+	cd examples && g++ surface.cpp -I/usr/include/python2.7 -lpython2.7 -o surface -std=c++11
+
+fill_inbetween: examples/fill_inbetween.cpp matplotlibcpp.h
+	cd examples && g++ fill_inbetween.cpp -I/usr/include/python2.7 -lpython2.7 -o fill_inbetween -std=c++11
+
+fill: examples/fill.cpp matplotlibcpp.h
+	cd examples && g++ fill.cpp -I/usr/include/python2.7 -lpython2.7 -o fill -std=c++11
+	
+update: examples/update.cpp matplotlibcpp.h
+	cd examples && g++ update.cpp -I/usr/include/python2.7 -lpython2.7 -o update -std=c++11
+
 clean:
-	rm -f examples/{minimal,basic,modern,animation,nonblock,xkcd,quiver}
+	rm -f examples/{minimal,basic,modern,animation,nonblock,xkcd,quiver,bar,surface,fill_inbetween,fill,update}

README.md

@@ -65,7 +65,7 @@ int main()
 
 ![Basic example](./examples/basic.png)
 
-matplotlib-cpp doesn't require C++11, but will enable some additional syntactic sugar when available:
+Alternatively, matplotlib-cpp also supports some C++11-powered syntactic sugar:
 ```cpp
 #include <cmath>
 #include "matplotlibcpp.h"
@@ -159,6 +159,36 @@ int main()
 
 ![quiver example](./examples/quiver.png)
 
+When working with 3d functions, you might be interested in 3d plots:
+```cpp
+#include "../matplotlibcpp.h"
+
+namespace plt = matplotlibcpp;
+
+int main()
+{
+    std::vector<std::vector<double>> x, y, z;
+    for (double i = -5; i <= 5;  i += 0.25) {
+        std::vector<double> x_row, y_row, z_row;
+        for (double j = -5; j <= 5; j += 0.25) {
+            x_row.push_back(i);
+            y_row.push_back(j);
+            z_row.push_back(::std::sin(::std::hypot(i, j)));
+        }
+        x.push_back(x_row);
+        y.push_back(y_row);
+        z.push_back(z_row);
+    }
+
+    plt::plot_surface(x, y, z);
+    plt::show();
+}
+```
+
+**Result:**
+
+![surface example](./examples/surface.png)
+
 Installation
 ------------
 
@@ -186,6 +216,16 @@ find_package(PythonLibs 2.7)
 target_include_directories(myproject PRIVATE ${PYTHON_INCLUDE_DIRS})
 target_link_libraries(myproject ${PYTHON_LIBRARIES})
 ```
+
+# C++11
+
+Currently, c++11 is required to build matplotlib-cpp. The last working commit that did
+not have this requirement was `717e98e752260245407c5329846f5d62605eff08`.
+
+Note that support for c++98 was dropped more or less accidentally, so if you have to work
+with an ancient compiler and still want to enjoy the latest additional features, I'd
+probably merge a PR that restores support.
+
 # Python 3
 
 This library supports both python2 and python3 (although the python3 support is probably far less tested,

contrib/CMakeLists.txt

@@ -23,3 +23,4 @@ add_executable(modern ${CMAKE_CURRENT_SOURCE_DIR}/../examples/modern.cpp)
 add_executable(animation ${CMAKE_CURRENT_SOURCE_DIR}/../examples/animation.cpp)
 add_executable(nonblock ${CMAKE_CURRENT_SOURCE_DIR}/../examples/nonblock.cpp)
 add_executable(xkcd ${CMAKE_CURRENT_SOURCE_DIR}/../examples/xkcd.cpp)
+add_executable(bar ${CMAKE_CURRENT_SOURCE_DIR}/../examples/bar.cpp)

examples/bar.cpp

@@ -0,0 +1,18 @@
+#define _USE_MATH_DEFINES
+
+#include <iostream>
+#include <string>
+#include "../matplotlibcpp.h"
+namespace plt = matplotlibcpp;
+
+int main(int argc, char **argv) {
+    std::vector<int> test_data;
+    for (int i = 0; i < 20; i++) {
+        test_data.push_back(i);
+    }
+
+    plt::bar(test_data);
+    plt::show();
+
+    return (0);
+}

examples/bar.png

@@ -0,0 +1,35 @@
+#define _USE_MATH_DEFINES
+#include "../matplotlibcpp.h"
+#include <cmath>
+
+using namespace std;
+namespace plt = matplotlibcpp;
+
+// Example fill plot taken from:
+// https://matplotlib.org/gallery/misc/fill_spiral.html
+int main() {
+    // Prepare data.
+    vector<double> theta;
+    for (double d = 0; d < 8 * M_PI; d += 0.1)
+        theta.push_back(d);
+
+    const int a = 1;
+    const double b = 0.2;
+
+    for (double dt = 0; dt < 2 * M_PI; dt += M_PI/2.0) {
+        vector<double> x1, y1, x2, y2;
+        for (double th : theta) {
+            x1.push_back( a*cos(th + dt) * exp(b*th) );
+            y1.push_back( a*sin(th + dt) * exp(b*th) );
+
+            x2.push_back( a*cos(th + dt + M_PI/4.0) * exp(b*th) );
+            y2.push_back( a*sin(th + dt + M_PI/4.0) * exp(b*th) );
+        }
+
+        x1.insert(x1.end(), x2.rbegin(), x2.rend());
+        y1.insert(y1.end(), y2.rbegin(), y2.rend());
+
+        plt::fill(x1, y1, {});
+    }
+    plt::show();
+}

examples/fill.cpp

@@ -0,0 +1,24 @@
+#include "../matplotlibcpp.h"
+
+#include <cmath>
+
+namespace plt = matplotlibcpp;
+
+int main()
+{
+    std::vector<std::vector<double>> x, y, z;
+    for (double i = -5; i <= 5;  i += 0.25) {
+        std::vector<double> x_row, y_row, z_row;
+        for (double j = -5; j <= 5; j += 0.25) {
+            x_row.push_back(i);
+            y_row.push_back(j);
+            z_row.push_back(::std::sin(::std::hypot(i, j)));
+        }
+        x.push_back(x_row);
+        y.push_back(y_row);
+        z.push_back(z_row);
+    }
+
+    plt::plot_surface(x, y, z);
+    plt::show();
+}

examples/fill.png

@@ -0,0 +1,60 @@
+#define _USE_MATH_DEFINES
+#include <cmath>
+#include "../matplotlibcpp.h"
+#include <chrono>
+
+namespace plt = matplotlibcpp;
+
+void update_window(const double x, const double y, const double t,
+                   std::vector<double> &xt, std::vector<double> &yt)
+{
+    const double target_length = 300;
+    const double half_win = (target_length/(2.*sqrt(1.+t*t)));
+
+    xt[0] = x - half_win;
+    xt[1] = x + half_win;
+    yt[0] = y - half_win*t;
+    yt[1] = y + half_win*t;
+}
+
+
+int main()
+{
+    size_t n = 1000;
+    std::vector<double> x, y;
+
+    const double w = 0.05;
+    const double a = n/2;
+
+    for (size_t i=0; i<n; i++) {
+        x.push_back(i);
+        y.push_back(a*sin(w*i));
+    }
+
+    std::vector<double> xt(2), yt(2);
+
+    plt::title("Tangent of a sine curve");
+    plt::xlim(x.front(), x.back());
+    plt::ylim(-a, a);
+    plt::axis("equal");
+
+    // Plot sin once and for all.
+    plt::named_plot("sin", x, y);
+
+    // Prepare plotting the tangent.
+    plt::Plot plot("tangent");
+
+    plt::legend();
+
+    for (size_t i=0; i<n; i++) {
+        if (i % 10 == 0) {
+            update_window(x[i], y[i], a*w*cos(w*x[i]), xt, yt);
+
+            // Just update data for this plot.
+            plot.update(xt, yt);
+
+            // Small pause so the viewer has a chance to enjoy the animation.
+            plt::pause(0.1);
+        }
+   }
+}