+
HELP
+
+
How does it work?
+When you submit a javascript to the server, it will be executed
+on a sandbox on the server. Before the event is loaded from a file
+and made available within the sandbox. Generally, the sandbox
+can easily be enhanced, e.g. with algorithms available in php.
+This can be done on request. After execution, the result returned
+by the script is then displayed in the camera display.
+
+
Why Javascript?
+Simply for security reasons. To avoid tranferring the event to the client's
+browser, the script must be executed on the server side. Also Python
+and PHP offer the possibility to execute scripts within a program,
+they do not have any security feature to avoid for exmple access to the
+local disk. The V8 Javascript engine however, is very limited in
+functionality and therefore ideally suited for a sandboxed and
+therefore safe excution on the server. Any other solution is welcome.
+
+
Javascript hints!
+Please note that in Javascript only basic data typed (number, etc)
+are copied in an assignment. In all other cases, only a reference
+is copied. For example, the following code snippet does not return 2
+as you might expect but 7!
+
+var arr = [ 0, 1, 2, 3 ];
+var cpy = arr;
+cpy[2] = 7;
+print(arr[2]);
+
+To avoid that, the global namespace implements a clone function.
+For exmaple, the following code snippet will return the expected output:
+
+var arr = [ 0, 1, 2, 3 ];
+var cpy = $.clone(arr);
+cpy[2] = 7;
+print(arr[2]);
+
+
+
The global object $
+
+The environment provides a global object (namesapce) called $ with the following members:
+
+| $.event | The event header information as obtained from the file |
+| $.event.numEvents | Number of events in the file |
+| $.event.numRoi | Number of samples per pixel |
+| $.event.numPix | Number of pixels |
+| $.event.eventNumber | Event number |
+| $.event.triggerNumber | Trigger number |
+| $.event.triggerType | Trigger type |
+| $.event.unixTime[2] | Timestamp when the event arrived at the event builder |
+| $.data[numPix][numRoi] | Theevent data |
+
+
+
Editor 1 (proc)
+
+
proc can return an array with numRoi entries or an array with up to
+four sub-arrays each of nRoi entries. They will be displayed in the graph.
+The chosel pixel is available as
pixel.
+The most simple is to just return the selected pixel data unprocssed:
+
+return $.data[pixel];
+
+
+
Editor 2 (main)
+
main should return extracted data per pixel. As
proc it can
+return a single array or an array with up to four sub-arrays each with
+numPix entries. They are displayed in the camera displays. The function
+implemented as
proc is accessible as
proc(i) with
i
+being available in
proc as
pixel. A very simple extractor
+could be to return just the sample at the trigger position
+
+var rc = [];
+for (var i=0; i<$.event.numPix; i++)
+ rc[i] = $.data[i][60];
+return rc;
+
+or taking the data pre-procesed by the code of the
proc-function:
+
+var rc = [];
+for (var i=0; i<$.event.numPix; i++)
+ rc[i] = proc(i)[60];
+return rc;
+
+
+Note that the precise access to the result of proc might depend on what
+exactly is retruned by proc (an array, or an array with sub-arrays).
+
+
The editor
+Key bindings of the editor can be found at
+
Codemirror.
+In addition the following binding are defined: Tab - Auto indent;
+F11 - Switch to fullscreen; Esc - In fullscreen mode to
+leave fullscreen; Ctrl-r - replace; Ctrl-y - Delete the line under the cursor;
+Ctrl-. (dot) - Fold code; Ctrl-Down (cursor down) - Autocomplete.
+
+
How to change the file?
+Start typing the date in the filename field. The available files
+will be filtered as you type. To select a file you need to select
+it fom the pull down.
+
+
How to change the displayed pixel?
+Enter the pixel number on the corresponding field or its hwardware
+address. As soon as you acknowledge your change (e.g. remove focus
+by clicking somewhere else) the pixel contents gets displayed.
+
+
How to Save/Load a script?
+To load a file choose a file fro your local hard drive via the
+file selection dialog. To save the contents of the editor, press
+Save.
+
+
Submit
+If you have changed the script and you want to run it on the current event
+press Submit. The Javascript will be executed for this event on
+the server.
+
+
+
+
Pixel value
+To display the value returned for a pixel just click on the pixel.
+The value will be displayed in the Pixel field. This will also
+display the corresponding waveform in the graph.
+
+
Min/max values
+Min and max values for the plot and the graph can be determined
+automatically or manully. To set the to a fixed value, enable the
+min and/or max field and enter the value of your choice. It will
+survive changing files, events or pixel.
+
+
Why is loading the page so slow?
+The total contents of the javascript libraries is about 1MB which
+all have to be treasferred to the browser. In addition the loading
+and processing of the event takes up to 1s so that the loading
+time of the page might be untypically slow. Once finished,
+the amaount of code to load can be decreased.
+
+
How to unzoom the plot?
+Double click on the plot.
+
+