a_slider = widgets.IntSliderWidget(min=-5, max=5, step=1, value=0)
b_slider = widgets.FloatSliderWidget(min=-5, max=5, step=0.3, value=0)
w = widgets.interactive(sigmoid_demo, a=a_slider, b=b_slider)
display(w)
IPython notebook interactive function: how to set the slider range