title: Cubic interpolation with derivatives in numpy
body: <p>A recent immigrant to Python and scientific computing with Python. This is a question to avoid any duplication of code that might already exist.</p>
  
  <p>I have a field that is sampled as a function of x and y in a regular grid. I would want to interpolate the data to obtain not only the value of the field at any point on the grid, but also the first and second derivatives. If I interpolate it with bicubic interpolation using interp2d, I can obtain the value of the field.</p>
  
  <p>Does anyone have a suggestion on how to obtain the first and second derivatives of the field using an EXISTING numpy or scipy function?</p>
  
  <p>Thanks!</p>