== ncap2 ==

the most powerful and quickly evolving tool from the nco set of functions

See the file of exemples : {{:reunions_orchidee:ncap2.pdf| ncap2 file}} or search what you are looking on this growing list of answers [[http://sourceforge.net/search/index.php?words=&sort=posted_date&sortdir=desc&offset=0&group_id=3331&type_of_search=forums|forum nco]]

A simple exemple showing different capacities (creation of a variable, use of a mask, call to an attribute, count the total and the size of the field (we can restrict this operation to a dimension as shown on the second line)

<code>
 ncap2 -O -s 'missing_flag[$y,$x]=0;where(t2m_daily!=t2m_daily@missing_value) missing_flag=1;missing_count=float(missing_flag.total())/missing_flag.size();print(missing_count)' stomate_restart.nc  ~/foo.nc
 ncap2 -O -s 'missing_flag[$y,$x]=0;where(t2m_daily!=t2m_daily@missing_value) missing_flag=1;missing_count=float(missing_flag.total($x))/missing_flag.size($x);print(missing_count)' stomate_restart.nc  ~/foo.nc
</code>


== cdo ==

A command that handle many operations one would like to do when working on outputs of models of the Earth System :
  * changing of time axis
  * regridding (many grid are already implemented and it is an even more versatile tool)
  * complex operations...

See the website of the project {{https://code.zmaw.de/projects/cdo/wiki}} or the doc : {{:reunions_orchidee:cdo-manual.pdf| CDO Manual}} and  the  {{:reunions_orchidee:cdo_refcard.pdf | quickref}}

<code>
cdo -v # print list of available operators [[BR]]
cdo -V # version (if very old, think of downloading the source and install a new version, as it is a tool that is evolving quickly [[BR]]
cdo -h remapcon # informations about a command [[BR]]
cdo remapcon,my_grid my_climatology.nc my_regridded_climatology.nc # conservative regridding to an other resolution [[BR]]
</code>

my_grid could be a file like :<code>
gridtype  = lonlat
gridsize  = 220
xname     = longitude
xunits    = degrees_east
yname     = latitude
yunits    = degrees_north
xsize     = 20
ysize     = 11
xfirst    = -18.75
xinc      = 3.75
yfirst    = 20