import plotly.plotly as py import plotly.graph_objs as go from plotly.tools import FigureFactory as FF import numpy as np import pandas as pd import scipy
Interpolation refers to the process of generating data points between already existing data points. Extrapolation is the process of generating points outside a given set of known data points.
(inter and extra are derived from Latin words meaning 'between' and 'outside' respectively)
Interpolate for a set of points and generate the curve of best fit that intersects all the points.
from scipy import interpolate x = np.arange(-5.0, 5.0, 0.25) y = np.arange(-5.0, 5.0, 0.25) xx, yy = np.meshgrid(x, y) z = np.sin(xx**2+yy**2) f = interpolate.interp2d(x, y, z, kind='cubic') xnew = np.arange(-5.0, 5.0, 1e-1) ynew = np.arange(-5.0, 5.0, 1e-1) znew = f(xnew, ynew) trace1 = go.Scatter3d( x=x, y=y, z=z[0, :], mode='markers', name='Data', marker = dict( size = 7 ) ) trace2 = go.Scatter3d( x=ynew, y=xnew, z=znew[0, :], marker=dict( size=3, ), name='Interpolated Data' ) layout = go.Layout( title='Interpolation and Extrapolation in 2D', scene=dict( camera= dict( up=dict(x=0, y=0, z=1), center=dict(x=0, y=0, z=0), eye=dict(x=1, y=-1, z=0) ) ) ) data = [trace1, trace2] fig = go.Figure(data=data, layout=layout) py.iplot(fig, filename='interpolation-and-extrapolation-2d')