In dankelley/oce: Analysis of Oceanographic Data

Questions regarding the AD2CP format

1. Question: Within a given AD2CP file, if the first instance of type "X" (say, "burst" type, "average" type, etc.) has a particular configuration, then can we assume that all the other instances of that type in that file will have identical configuration? For example, if echosounder data are present in the first instance of "burst", will they be present in all the others?

Background: If so, then oce can use vectorized code, which is important for speed and code simplicity.

1. Question: How are checksums to be calculated, in modern C, i.e. phrased in terms of e.g. uint16, rather than unsigned short?

Background: I have seen manuals with two different expressions of the checksum calculation. The scheme used in oce, which has been in-place for many years and used often for several types of Nortek files, fails for test file S102791A002_Barrow_v2_avgd.ad2cp^[The test files are in the tests/testthat/local_data directory of the "develop" branch of the repository at http://www.github.com/dankelley/oce.].

1. Question: What is data-chunk-type 0x23?

Background: Oce detects this in test file ad2cp_01.ad2cp$^1$, but the string 0x23 is not present in either of the first two documents cited below, and is not identified as what oce calls a "chunk type" in the third document.

1. Question: is there documentation on files with 12-byte headers?

Background: Test file ad2cp_01.ad2cp$^1$ has this format.

References

Nortek AS. “Signature Integration 55|250|500|1000kHz (2017).” Nortek AS, 2017.

Nortek AS. “Signature Integration 55|250|500|1000kHz (2018).” Nortek AS, 2018.

Nortek AS. “Signature Integration 55|250|500|1000kHz (2022).” Nortek AS, March 31, 2022.

dankelley/oce documentation built on May 8, 2024, 10:46 p.m.