improved calc with an easy plot function

modified:   .local/bin/dropdowncalc

.local/bin/dropdowncalc

@@ -1,2 +1,13 @@
 #!/bin/sh
-ifinstalled python && python -iq -c "print('Welcome to the Calculator'); from numpy import *; import sys; sys.ps1='❯'"
+ifinstalled python && python -iq -c "print('Welcome to the Calculator')
+from numpy import *
+import sys
+import matplotlib.pyplot as plt
+sys.ps1='❯'
+
+def plot(a, b, f):
+    x = linspace(a, b, 1000)
+    y = eval(f)
+    plt.plot(x, y)
+    plt.show()
+"