====== BandRatios ======
BandRatios (Hoku 3.2) takes the ratio of every band of a multiband image with every band that follows it. Ratios with the bands before it would be redundant, so an image with N bands gives N(N−1)/2 output bands.

===== Order of the output bands =====
  * The first N−1 bands pair band 0 with bands 1 to N−1.
  * The next N−2 bands pair band 1 with bands 2 to N−1.
  * And so on, until the last band, which pairs band N−2 with band N−1.

For example, a 4-band image gives 6 output bands, for the pairs (0, 1), (0, 2), (0, 3), (1, 2), (1, 3) and (2, 3).

===== Arguments =====
^ Argument ^ What it does ^ Default ^
| operation | The **ratio** or the **difference** of each pair of bands | ratio |
| output bits | Floating point, 32-bit or 64-bit | 32 |
| bandsOut | Output only the first M bands (bands 0 to M−1). Useful because the number of bands grows quickly | all |

The input must have more than one band, and can be byte, integer or floating point. The output is floating point.