# annulus_integrals

annulus_integrals, a Python code which returns the exact value of the integral of any monomial over the interior of an annulus centered at the origin.

The interior of the disk is defined by

```        r1^2 <= x^2 + y^2 <= r2^2
```

The integrands are all of the form

```        f(x,y) = x^e1 * y^e2
```
where the exponents are nonnegative integers. If any exponent is an odd integer, the integral will be zero. Thus, the "interesting" results occur when all exponents are even.

### Languages:

annulus_integrals is available in a MATLAB version and an Octave version and a Python version.

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### Source Code:

Last revised on 06 November 2022.