Description
Type
Data Process.
Behaviour
It executes an aggregation function on a datacube with respect to explicit dimensions.
Parameters
- cube: name of the input datacube. The name must be in PID format.
- schedule: scheduling algorithm. The only possible value is 0, for a static linear block distribution of resources.
- group_size: number of tuples per group to consider in the aggregation function. If set to “all” the aggregation, will occur on all tuples of the table.
- operation: reduction operation. Possible values are “count”, “max”, “min”, “avg” and “sum”.
- missingvalue: value to be considered as missing value; by default it is NAN (for float and double).
- grid: optional argument used to identify the grid of dimensions to be used (if the grid already exists) or the one to be created (if the grid has a new name). If it isn’t specified, no grid will be used.
- container: name of the container to be used to store the output cube; by default it is the input container.
- check_grid: optional flag to be enabled in case the values of grid have to be checked (valid only if the grid already exists).
- description: additional description to be associated with the output cube.
System parameters
- exec_mode: operator execution mode. Possible values are async (default) for asynchronous mode, sync for synchronous mode with json-compliant output.
- ncores: number of parallel processes to be used (min. 1).
- nthreads: number of parallel threads per process to be used (min. 1).
- sessionid: session identifier used server-side to manage sessions and jobs. Usually, users don’t need to use/modify it, except when it is necessary to create a new session or switch to another one.
- objkey_filter: filter on the output of the operator written to file (default=all => no filter, none => no output, aggregate => shows operator’s output PID as text).
Examples
Compute the maximum values of 10-tuple groups in the datacube identified by the PID “URL/1/1”:
[OPH_TERM] >> oph_aggregate operation=max;group_size=10;cube=URL/1/1;grid=new_grid;
