Updated simple example (added to README.md)

Author: PierreRaybaut

README.md

@@ -79,7 +79,7 @@ From the source package:
 python setup.py install
 ```
 
-## Examples/tests
+## Examples (tests)
 
 The GUI-based test launcher may be executed from Python:
 
@@ -93,3 +93,21 @@ or from the command line:
 ```bash
 PythonQwt-tests
 ```
+
+## Sample
+
+```python
+import qwt
+import numpy as np
+
+app = qwt.qt.QtGui.QApplication([])
+x = np.linspace(-10, 10, 500)
+plot = qwt.QwtPlot("Trigonometric functions")
+plot.insertLegend(qwt.QwtLegend(), qwt.QwtPlot.BottomLegend)
+qwt.QwtPlotCurve.make(x, np.cos(x), "Cosinus", plot, linecolor="red", antialiased=True)
+qwt.QwtPlotCurve.make(x, np.sin(x), "Sinus", plot, linecolor="blue", antialiased=True)
+plot.resize(600, 300)
+plot.show()
+```
+
+<img src="https://raw.githubusercontent.com/PierreRaybaut/PythonQwt/master/doc/images/QwtPlot_example.png">

doc/images/QwtPlot_example.png

@@ -1,24 +1,18 @@
-from qwt.qt.QtGui import QApplication
-from qwt import QwtPlot, QwtPlotCurve
+import qwt
 import numpy as np
-import os.path as osp
-
-app = QApplication([])
 
+app = qwt.qt.QtGui.QApplication([])
 x = np.linspace(-10, 10, 500)
-y1, y2 = np.cos(x), np.sin(x)
+plot = qwt.QwtPlot("Trigonometric functions")
+plot.insertLegend(qwt.QwtLegend(), qwt.QwtPlot.BottomLegend)
+qwt.QwtPlotCurve.make(x, np.cos(x), "Cosinus", plot, linecolor="red", antialiased=True)
+qwt.QwtPlotCurve.make(x, np.sin(x), "Sinus", plot, linecolor="blue", antialiased=True)
+plot.resize(600, 300)
+plot.show()
 
-my_plot = QwtPlot("Two curves")
-curve1, curve2 = QwtPlotCurve("Curve 1"), QwtPlotCurve("Curve 2")
-curve1.setData(x, y1)
-curve2.setData(x, y2)
-curve1.attach(my_plot)
-curve2.attach(my_plot)
-my_plot.resize(600, 300)
-my_plot.replot()
-my_plot.show()
+import os.path as osp
 
-my_plot.grab().save(
+plot.grab().save(
     osp.join(osp.abspath(osp.dirname(__file__)), "images", "QwtPlot_example.png")
 )
 

doc/plot_example.py

@@ -239,26 +239,17 @@ class QwtPlot(QFrame, QwtPlotDict):
     The following example is a good starting point to see how to set up a 
     plot widget::
     
-        from .qt.QtGui import QApplication
-        from qwt import QwtPlot, QwtPlotCurve
+        import qwt
         import numpy as np
 
-        app = QApplication([])
-
+        app = qwt.qt.QtGui.QApplication([])
         x = np.linspace(-10, 10, 500)
-        y1, y2 = np.cos(x), np.sin(x)
-
-        my_plot = QwtPlot("Two curves")
-        curve1, curve2 = QwtPlotCurve("Curve 1"), QwtPlotCurve("Curve 2")
-        curve1.setData(x, y1)
-        curve2.setData(x, y2)
-        curve1.attach(my_plot)
-        curve2.attach(my_plot)
-        my_plot.resize(600, 300)
-        my_plot.replot()
-        my_plot.show()
-
-        app.exec_()
+        plot = qwt.QwtPlot("Trigonometric functions")
+        plot.insertLegend(qwt.QwtLegend(), qwt.QwtPlot.BottomLegend)
+        qwt.QwtPlotCurve.make(x, np.cos(x), "Cosinus", plot, linecolor="red", antialiased=True)
+        qwt.QwtPlotCurve.make(x, np.sin(x), "Sinus", plot, linecolor="blue", antialiased=True)
+        plot.resize(600, 300)
+        plot.show()
         
     .. image:: /images/QwtPlot_example.png