Page History

...

XTC Explorer - GUI interface that builds pyana modules for you.

xtcexplorer /reg/d/psdm/xpp/xppi0310/xtc/e81-r0098-s0*
{none}
Then hit the "Scan File(s)" button (can you find it?!?)

What do you see? Compare the GUI that pops up, with the output in the terminal window. 

h2. Extracting the data with pyana, some examples

...

h3. Outline of a pyana module

...

Like the other frameworks, pyana is an executable that loops through the XTC file and calls all

...

 
requested user modules at certain transitions. All the analysts need to do is to fill in the

...

 
relevant functions in their user analysis module:

1. useful

...

1. imports

...

1. 
   import

...

1. numpy

...

1. as

...

1. np

...

1. 
   import

...

1. matplotlib.pyplot

...

1. as

...

1. plt

...

1. 
   from

...

1. pypdsdata.xtc

...

1. import

...

1. TypeId

...

class

...

mymodule

...

(object)

...

:

...

"""Class

...

whose

...

instance

...

will

...

be

...

used

...

as

...

a

...

user

...

analysis

...

module.

...

"""

...

def _init

...

_

...

(

...

self,
source = ""
threshold = "" ):
"""Class

...

constructor.

...

The parameters to the constructor are passed from pyana configuration file.
If parameters do not have default values here then the must be defined in
pyana.cfg. All parameters are passed as strings, convert to correct type before use.

@param source name of device, format 'Det-ID|Dev-

...

Point detector delay scan

...

ID'
@param threshold threshold value (remember to convert from string)
"""
self.source = source
self.threshold = float(threshold)

def beginjob( self, evt, env ) :
"""This method is called once at the beginning of the job. It should
do a one-time initialization possible extracting values from event
data (which is a Configure object) or environment.

@param evt event data object
@param env environment object
"""
pass

def beginrun( self, evt, env ) :
"""This optional method is called if present at the beginning of the new run.

@param evt event data object
@param env environment object
"""
pass

def begincalibcycle( self, evt, env ) :
"""This optional method is called if present at the beginning
of the new calibration cycle.

@param evt event data object
@param env environment object
"""
pass

def event( self, evt, env ) :
"""This method is called for every L1Accept transition.

@param evt event data object
@param env environment object
"""
pass

def endcalibcycle( self, env ) :
"""This optional method is called if present at the end of the
calibration cycle.

@param env environment object
"""
pass

def endrun( self, env ) :
"""This optional method is called if present at the end of the run.

@param env environment object
"""
pass

def endjob( self, env ) :
"""This method is called at the end of the job. It should do
final cleanup, e.g. close all open files.

@param env environment object
"""
pass

h3. Point detector delay scan

* *Fetching the ControlPV information:*
ControlPV is available from the {{env}} object, and since it only changes at the beginning 
of each calibration cycle, the {{begincalibcycle}} function is the appropriate place to get it: 
\\
{code:none}

...

    def begincalibcycle( self, evt, env ) :

The ControlConfig object may contain several pvControl and pvMonitor objects. In this case
there's only one, but make sure the name matches anyway:

        ctrl_config = env.getConfig(TypeId.Type.Id_ControlConfig)

        for ic in range (0, ctrl_config.npvControls() ):
            cpv = ctrl_config.pvControl(ic)
            if cpv.name()=="fs2:ramp_angsft_target":

                # store the value in a class variable (visible in every class method)
                self.current_pv_value = cpv.value() )

• Fetching the IPIMB and PhaseCavity information:
  All the other information that we need, is available through the evt object, and
  event member function is the place to get it:
  

  Code Block
  none none
  def event( self, evt, env ) :

  
  Use "XppSb3Ipm-1|Ipimb-0" (a.k.a. IPM3) sum of all channels for normalization and filtering
  

  Code Block
  none none
  ipmN_raw = evt.get(TypeId.Type.Id_IpimbData, "XppSb3Ipm-1|Ipimb-0") ipmN_fex = evt.get(TypeId.Type.Id_IpmFex, "XppSb3Ipm-1|Ipimb-0") ipmN_norm = ipmN_fex.sum

  
  Use "XppSb3Pim-1|Ipimb-0" (a.k.a. PIM3) channel 1 as signal
  

  Code Block
  none none
  ipmS_raw = evt.get(TypeId.Type.Id_IpimbData, "XppSb3Pim-1|Ipimb-0" ) ipmS_fex = evt.get(TypeId.Type.Id_IpmFex, "XppSb3Pim-1|Ipimb-0" ) ipm_sig = ipmS_fex.channel[1]

  
  Get the phase cavity:
  

  Code Block
  none none
  pc = evt.getPhaseCavity() phasecav1 = pc.fFitTime1 phasecav2 = pc.fFitTime2 charge1 = pc.fCharge1 charge2 = pc.fCharge2

  
  Compute delay time and fill histograms
  

  Code Block
  none none
  delaytime = self.current_pv_value + phasecav1*1e3 # The "histograms" are nothing but python lists. Append to them, and turn them into arrays at the end. self.h_ipm_rsig.append( ipm_sig ) self.h_ipm_nsig.append( ipm_sig/ipm_norm ) self.h_delaytime.append( delaytime )

...