Aided by the above information, YODA does (in fact, the user routines
do) the required data processing, and produce histograms or calculated
values as results. Calculated values can simply be printed out,
appearing on the controlling terminal. To do formatting, the full
printf functionality can be used.
Histograms are just filled by YODA, and can be inspected by the internal display or may be copied to a shared memory area between YODA and the displaying process (PAW++; currently not supported on at least DEC UNIX). The calls for defining and filling histograms are very much like the calls from the CERN hbook library (apart from the transfer to paw, no hbook routines are actually used). In most cases, however, YODAs own display will be sufficient for data visualization.
Cuts (one- or two-dimensional criteria on the data, often also known as gates), are also declared by the user tasks. Their actual definition, however, is read from files. PAW can be used to produce the definitions interactively and save them to file. These definitions can be read from the user task or interactively via YODA's pulldown-menu. This also allows the user to change them ''by hand'' or with another text processing tool, since the cut definitions are plain ASCII format.