If YODA is not active, start it first as you did before. To shorten things up, you can also select the input datasource with appropriate commandline parameters. Type:
yoda -p "server -D 20"
This should give you the same result as starting YODA first and then
selecting the inputprocess to be server -D 20.
Then, load the example above into YODA, and push Start/Continue
state. You should see that events are being processed. Furthermore, if
you select Histograms from the Show pulldown-menu, you
should also see the two histograms that you defined being displayed.
Note the increasing number of entries as the analysis goes on. Now it's
time to look at them graphically.
The easiest way to do this job is to use the internal display of yoda. At first, you have to enable it by choosing on from the display menu. Now you have two more windows: one titled "zoni" and the other titled "display". The zoni is a very simple histogram manager. It is used for tasks concerning the selection and arrangement of histograms. The display is a "canvas" showing the selected histograms. Also, it allows you to act on one instance of a histogram, e.g. performing a zoom.
Now you can browse your histograms by clicking with mouse button three on the desired histogram in the zoni listbox. If you want to view more than one histogram at once, use the button matrix to enable displaying that number of histograms. Histograms are added by double-clicking with mouse button one, while button three replaces the current one. Further capabilities like zooming, logarithmic axes, probing, printing etc. are described by the yoda help menu.
Another possibility is to use
PAW++ for visualization. The first way is to write an hbook
file and read this file with PAW++. Histograms are written using the
Histogram menu or by typing
histowrite filename
in the xterm yoda is running in.
This is fine if you are interested
to save your histograms for future use. The other way is to use
histogram transfer via global section (not available on all
platforms).
To use the global section, it must be enabled when starting up yoda,
e.g.
yoda -t 15 -p "server -D 20"
which will update the global section every 15 seconds.
Then start PAW++ by typing:
paw++
Then, three windows should appear additionally to your existing YODA
and terminal windows.
In the Input Pad of the Paw++ Executive Window, enter:
global yoda
SPMampcd //yoda; hrin *&
These commands tell PAW++ to link itself to the shared memory area
created by YODA (which is addressed by its name: yoda), then to change
to this shared memory as the current working space, and then read in
all histograms. The histograms should then appear in the PAWC
area. Check this by clicking on the PAWC entry in the Paw++ main browser, and see histograms appearing in the space beneath
it. Then, double-click on one of the histograms to get it displayed in
the graphic window. You can display the other one as well by
double-clicking on its entry in the main browser.
To update the state of the histograms (which should still be being filled
in the meantime), recall the command
SPMampcd //yoda; hrin *&
with the cursor keys in the executive window (or reenter the command),
to get the current contents of the histograms into the PAWC
area.
You can now redisplay, fit, copy, add, print or whatever you want to do with them. See a PAW++ manual (if you can get one) for details.
To get a continuously updating display, you should define yourself a
loop macro in a file e.g. like this (in a file loop.kumac):
oncemore: zone 1 2 cd //yoda; hrin * cd //pawc h/plo * wait 5 ' ' h/del * goto oncemore
If this is executed by entering exec loop
or clicking on the appropriate entry from the macro section in
the main browser, the histograms will be shown updating in a 5 second
interval while they are being filled.
You can stop this any time by typing ^C (Control-C) in the
executive window.
While this should be sufficient for a first try, you should now either play around on this level (using YODA's dummy mode), or get right into your ''real analysis''.
You should read the reference section next to get an overview over YODA's complete command set and features.