Visualising ODB in Magics
There are several ways on visualisating ODB data in Magics.
- use the ODB Magics objects. This allows Magics to read a odb file and extract some columns for geographical plots or graph.
- In python, it also possible to use odb_api packages to create a numpy array and pass the values in memeoty to Magics. magics is then able to perform symbol plotting on a geographical area, time series, etc ..
This page will present examples of these different plottings, and will offer skeletons of python programs.
Using an ODB file and create a geographical map
In this example, we have downloaded some ODB data from Mars.
The mars request looks like:
Mars request
retrieve,
class = e2,
type = ofb,
stream = oper,
expver = 1607,
repres = bu,
reportype = 16005,
obstype = 1,
date = 20100101,
time = 0,
domain = g,
target = "data.odb",
filter = "select lat@hdr, lon@hdr, obsvalue@body where (source='ispdv2.2') and (varno=110)",
duplicates = keep
We retrieve 3 columns lat@hdr, lon@hdr, obsvalue@body. In that case obsvalue@body will contain the value of the Surface pressure in Pascal.
We can dump the result :
odb ls
lat@hdr lon@hdr obsvalue@body 84.559998 -44.100006 100180.000000 84.349998 -46.989990 100140.000000 83.610001 -89.299988 100380.000000 83.419998 -71.970001 100140.000000 83.300003 -69.040009 100090.000000 82.480003 -93.190002 100350.000000 82.449997 -170.309998 101510.000000 82.260002 -128.949997 99180.000000 81.449997 -144.850006 100180.000000 81.419998 -144.619995 100180.000000 81.400002 -145.550003 100250.000000 80.709999 -110.500000 100180.000000 80.320000 -179.860001 102969.992188 80.019997 -151.399994 100440.000000