## Accuracy of nfft

I have investigated the accuracy of our nfft implementation for 1 and for 100 data points:

## Current implementation

### 1 data point

### 100 data points

## Alternative

We use the following criterion to decide on the oversampling factor:

`rat = 3 if eps < 1e-11 else 2`

If one always takes an oversampling factor of 2 we arrive at the following results

### 1 data point

### 100 data points

Therefore, my suggestion is to drop oversampling with a factor of three since it does not add relevant accuracy.

Here is the original paper for the code. Chapter 4 describes the algorithm which we use. nufft_paper.pdf

This is the code which produces the plots. gridding_accuracy.py