
* Use full OOP
* Data members:
- raw filename
- fixed final energy 
- nos data points (Ndp)
- nos of Pixels (Npix)
- energy transfer vector (Ndp long)
- Counts for each data (Ndp vectors each Npix long) (Ndp x Npix array)

- Intensity treshold for Gaussian fits (def is 15)
- Gaussian fitted parameters (Ndp sets) (Ndp x 5 array)
- Flag to specify if overall Gaussian fit has been performed
- Flags (Ndp vector) to indicate if data point has been fitted

- Minimum pixel for efficiency/bkgd calc (use pixback for default)
- Maximum pixel for efficiency/bkgd calc (use pixback for default)

- 

- Calculated Ef vector (Npix long)
- Calculated efficiency vector (Npix long)

* Methods:
- gui builder
- Check raw file for appropriate format:
  1) Must be an ng5 ICP Q-buffer file
  2) Must contain PSD data taken in a+ mode
  3) Final energy must be fixed (not fixed Ei!) 
- Read dataset. Retrieve or record:
  + Raw data filename
  + Fixed final energy value / Analyzer energy (scaler)
  + Energy trasfer vector (Ndp vector)
  + Nos of data points (Ndp vector)
  + Counts (Ndp x Npix array)
  This function is triggered by  use action grom the GUI.
- Initialize data object using data from dataset
  + Fill all required data members using newly read data
  + Recalculate all necessary parameters
- Fit a single peak with a (Gaussian + bkgd) function
  + requires data point (index) to be fitted
  + fills out appropriate data members with fit results
- Calculate Efp by fitting gaussians. Deterimine central pixel for each data
  point, interpolate to determine Efp at each pixel. Store results in
  appropriate data members. This function should be triggered by a user action
  from the GUI.
- Calculate efficiencies for each pixel and store results in appropriate
  data members.

- Display full PSD image data in 2D.
- Display a single data point peak + fits, if fit has been performed for
  that data point. (GUI should enable user to cycle through all data points)
- Display calculated final energies for each pixel, Efp
- Display calculated efficiencies for each pixel, Sp
- Export graphics to postcript
- Export graphics to jpeg,png formats.


* GUI components
- Provide a main dialog to left for controlling parameters of app.
  + Menu to load raw calibration dataset
  + display raw calibration filename in use
  + Peak intensity threshold (default = 15)
  + Useful pixel range (min,max)
  + Options to switch between the various display outputs
  + Slider to select data point to display
  + Button to initiate calculation of Efp
  + Button to initiate calculation of Sp
  + Menu to export active graphics to postscript
  + Menu to export active graphics to jpeg,png
  + Menu to generate output calibration file 
  