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The myana user guide already has a lot of examples linked in! And here are a few more...

This page holds a few example code-snippets for use in myana analysis. This analysis is written in C++ and the examples here use root for plotting. Compare with Pyana user examples to see how the same things can be done using the pyana analysis framework.

Acqiris waveform data

This method is good for any waveform data from the Acqiris digitizers, just replace the source name (here AmoITof for the AMO Ion Time of flight detector) with some other Acqiris waveform detector.

Include and global variable definitions:

#include <TProfile.h>

static int        numChannelsITof;
static int        numSamplesITof;
static double     sampleIntervalITof;
static TProfile*  profileITof = NULL;

In beginjob(), read configuration data and book a profile histogram (for each sample interval (x-axis), draw the average number of samples (y-axis), i.e. the average waveform of all events).

  int fail = getAcqConfig( AmoITof, numChannelsITof, numSamplesITof, sampleIntervalITof);
  if ( fail != 0 )
    printf( "begin(): getAcqConfig() failed, code = %d\n", fail );

  profileITof = new TProfile("avg","avg",numSamplesITof,0.0,sampleIntervalITof,"");
  profileITof->SetYTitle("Volts");    //optional
  profileITof->SetXTitle("Seconds");  //optional

In the event() function, get the Acqiris value for this event and add it to the histogram. The getAcqValue function will point timeITof and voltageITof to arrays of readout values.

  double* timeITof;    // array: sample interval
  double* voltageITof; // array: readout values
  int channel = 0;
  int fail = getAcqValue( AmoITof, channel, timeITof, voltageITof);
  if ( fail != 0 )
  {
    printf( "event(): getAcqValue() failed, code = %d\n", fail );
  }
  else
  {
    for (i=0;i<numSamplesITof;i=i+1)
      {
        double t = timeITof[i];
        double v = voltageITof[i];
        profileITof->Fill(t,v);
      }
  }

The resulting histogram can be drawn in a root session and would look something like this:
Image Added

Beamline data (Bld)

To read out energy, charge and position of the beam from the beamline data, use getEBeam(). The function returns 0 if data is available and assignes values to its arguments from the current event. Call from within event().

  double ebcharge; double ebenergy; double posx; double posy;
  double angx; double angy;
  int fail =  getEBeam(ebcharge, ebenergy, posx, posy, angx, angy);
  if (!fail) printf("ebeam: %f, %f, %f, %f, %f, %f \n", 
                     ebcharge, ebenergy, posx, posy, angx, angy);

...

  double phaseCavityTime1, phaseCavityTime2, phaseCavityCharge1, phaseCavityCharge2;
  int fail = getPhaseCavity( phaseCavityTime1, phaseCavityTime2, phaseCavityCharge1, phaseCavityCharge2 );
  if (!fail) printf("PhaseCavity: %f, %f, %f, %f \n", 
                     phaseCavityTime1,  phaseCavityTime2, phaseCavityCharge1, phaseCavityCharge2);

...