Differences
This shows you the differences between two versions of the page.
Both sides previous revision Previous revision Next revision | Previous revision | ||
fimex:faq [2013-09-16 08:59:27] heikok |
fimex:faq [2024-07-03 07:11:55] (current) alexanderb opendap auth on jammy |
||
---|---|---|---|
Line 6: | Line 6: | ||
* Fimex does not use file-locks for reading: Graphical interfaces like [[http:// | * Fimex does not use file-locks for reading: Graphical interfaces like [[http:// | ||
- | * Fimex does not implement file-locking for writers generally, though in particularly with the fillWriter interface this situation might change, in particular for netcdf-files | + | * Fimex does not implement file-locking for writers generally, though in particularly with the [[http:// |
+ | |||
+ | |||
+ | ===== How can I change the units of a variable? ===== | ||
+ | |||
+ | If the original variable e.g. '' | ||
+ | |||
+ | If the input-file has the wrong units, e.g. Celsius while the data in fact is Kelvin, you should use the input.config=... and re-define the units-attribute. The data-values won't be changed. | ||
===== How to solve problems with a short variable? ===== | ===== How to solve problems with a short variable? ===== | ||
Line 26: | Line 34: | ||
In this example, the precipitation will be described with an accuracy of 0.1mm and up to 3276.7mm. The ncml-configfile will be applied right before writing with the '' | In this example, the precipitation will be described with an accuracy of 0.1mm and up to 3276.7mm. The ncml-configfile will be applied right before writing with the '' | ||
- | ===== Vector-rotation gives error-message (>= 0.48) and wrong values due to different units ===== | + | ===== Vector-rotation ===== |
+ | |||
+ | ==== Which vectors are auto-detected for rotation ==== | ||
+ | |||
+ | Vectors are autorotated if one of the following applies: | ||
+ | |||
+ | * the ''< | ||
+ | * the vector has a known CF-standard-name, | ||
+ | * x_wind, y_wind | ||
+ | * *_x_velocity, | ||
+ | * *_x_transport, | ||
+ | * *_x_displacement, | ||
+ | * *_eastward_*, | ||
+ | * the complete list can be found in the sources after '' | ||
+ | |||
+ | ==== Vector-rotation gives error-message (>= 0.48) and wrong values due to different units ==== | ||
When rotating vectors for spatial interpolations, | When rotating vectors for spatial interpolations, | ||
Line 125: | Line 148: | ||
</ | </ | ||
+ | === OpENDAP and slicing === | ||
+ | OpENDAP servers are often limited on how much data can be read at per request, e.g. thredds allows only 500MB binary data / 50MB ascii data per request before failing with an error like | ||
+ | < | ||
+ | syntax error, unexpected WORD_STRING, | ||
+ | context: Error { code = 403; message = " | ||
+ | terminate called after throwing an instance of ' | ||
+ | what(): | ||
+ | Aborted | ||
+ | </ | ||
- | ===== Why takes linking with '' | + | Fimex tries to subdevide requests into one unlimited slice per variable. Unfortunately, |
+ | < | ||
+ | <?xml version=" | ||
+ | <netcdf xmlns=" | ||
+ | xmlns: | ||
+ | xsi: | ||
+ | < | ||
+ | </ | ||
+ | </ | ||
- | This happens with older versions of gcc, seen with 3.3 on debian sarge. | ||
- | Use '' | + | ==== Authentication ==== |
+ | |||
+ | In theory, it should be possible to specify username and password | ||
+ | - in '' | ||
+ | - as part of the URL for example | ||
+ | |||
+ | Example '' | ||
+ | < | ||
+ | machine thredds.met.no | ||
+ | login XXXX | ||
+ | password YYYY | ||
+ | </ | ||
+ | |||
+ | Example '' | ||
+ | < | ||
+ | HTTP.NETRC=YOURHOME/ | ||
+ | |||
+ | HTTP.CREDENTIALS.USERNAME=XXXX | ||
+ | HTTP.CREDENTIALS.PASSWORD=YYYY | ||
+ | |||
+ | HTTP.USERNAME=XXXX | ||
+ | HTTP.PASSWORD=YYYY | ||
+ | </ | ||
+ | |||
+ | Unfortunately, this does not always seem to work as expected. | ||
+ | Known status of OpenDAP authentication support (applies to '' | ||
+ | * Specifying | ||
+ | * For Ubuntu 16.04 (xenial, EOL), both URL and netrc seem to work. | ||
+ | * For Ubuntu 18.04 (bionic), username and password cannot be read from netrc, but can be specified in the URL. | ||
+ | * For Ubuntu 20.04 (focal), username and password can only be read from netrc, but cannot be specified in the URL. | ||
+ | * For Ubuntu 22.04 (jammy), the only solution known to us is to add a '' | ||