Plotting method now takes a function as an argument.

.gitignore

@@ -1,2 +1,50 @@
 .DS_Store
+# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio and Webstorm
+# Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
 
+# User-specific stuff:
+.idea/**/workspace.xml
+.idea/**/tasks.xml
+.idea/dictionaries
+
+# Sensitive or high-churn files:
+.idea/**/dataSources/
+.idea/**/dataSources.ids
+.idea/**/dataSources.xml
+.idea/**/dataSources.local.xml
+.idea/**/sqlDataSources.xml
+.idea/**/dynamic.xml
+.idea/**/uiDesigner.xml
+
+# Gradle:
+.idea/**/gradle.xml
+.idea/**/libraries
+
+# CMake
+cmake-build-debug/
+
+# Mongo Explorer plugin:
+.idea/**/mongoSettings.xml
+
+## File-based project format:
+*.iws
+
+## Plugin-specific files:
+
+# IntelliJ
+/out/
+
+# mpeltonen/sbt-idea plugin
+.idea_modules/
+
+# JIRA plugin
+atlassian-ide-plugin.xml
+
+# Cursive Clojure plugin
+.idea/replstate.xml
+
+# Crashlytics plugin (for Android Studio and IntelliJ)
+com_crashlytics_export_strings.xml
+crashlytics.properties
+crashlytics-build.properties
+fabric.properties

main.py

@@ -1,38 +1,49 @@
+import numpy as np
+from PyQt4 import QtGui
 from PyQt4.uic import loadUiType
-
-from matplotlib.figure import Figure
 from matplotlib.backends.backend_qt4agg import (
     FigureCanvasQTAgg as FigureCanvas,
     NavigationToolbar2QT as NavigationToolbar)
+from matplotlib.figure import Figure
+from sympy import *
 
 Ui_MainWindow, QMainWindow = loadUiType('window.ui')
 
+
+def f(x):
+    return np.sin(x);
+
+
 class Main(QMainWindow, Ui_MainWindow):
     def __init__(self, ):
         super(Main, self).__init__()
         self.setupUi(self)
+        self.fig1 = Figure()
 
-    def addmpl(self, fig):
+    def drawFig(self, fig):
         self.canvas = FigureCanvas(fig)
         self.mplvl.addWidget(self.canvas)
         self.canvas.draw()
         self.toolbar = NavigationToolbar(self.canvas,
                                          self.mplwindow, coordinates=True)
         self.mplvl.addWidget(self.toolbar)
 
-if __name__ == '__main__':
-    import sys
-    from PyQt4 import QtGui
-    import numpy as np
+    def plot(self, y):
+        plt = self.fig1.add_subplot(111)
+        xs = np.arange(-100.0, 100.0, 0.1)
+        plt.plot(xs, y(xs))
+        plt.axis([-6, 6, -1, 1])
+        self.drawFig(self.fig1)
 
+
+if __name__ == '__main__':
     app = QtGui.QApplication(sys.argv)
     main = Main()
     main.show()
 
-    #figure example
-    fig1 = Figure()
-    ax1f1 = fig1.add_subplot(111)
-    ax1f1.plot(np.random.rand(5))
-    main.addmpl(fig1)
+    # figure example
+    x = Symbol('x')
+    y = sin(x)
+    main.plot(lambdify(x, y.diff(x), 'numpy'))
 
     sys.exit(app.exec_())