title: python polynomial package of multiple variables
body: <p>I need to represent polynomials of several variables, i.e.</p>
  
  <pre><code>x^3 + xy^4 + xz^2w + uq^2we^3
  </code></pre>
  
  <p>I've looked at the scipy package and it appears it only handles polynomial up to 3 variables. The main operation I would like to perform with these polynomials are</p>
  
  <p>1) Multiplication of polynomials</p>
  
  <p>2) Integration against a single variable of the polynomial (definite intergral)</p>
  
  <p>3) Curve fitting the polynomial (of fixed variables and degrees) to data points</p>
  
  <p>Any lead will be helpful. it would be nice if someone already done a good job before I have to implement them. </p>
  
  <p>Also as a side note, I've never touched tensors but I suspect these operations is natural to express as a tensor of some sort? Is there any good tensor libraries instead that I could use and try to figure out how to express these operations as a tensor? Again I have not touched tensors at all but I can definitely learn it easy.</p>