Tools

SpecGrid

This is a separate tool which allows you to analyze Gridspectroscopy files. It is intended to cover only the basic features. More detailed analysis has to be done by the user.

We suggest for exmaple MatLab for this purpose.

Basics

Gridspectroscopy creates 2 files, one which contains the spectroscopy data in binary form (file extensionand .specgrid) a normal dat file which contains the related image (file extension .specgrid.dat). Specgrid files can be very large, therefore an original file can be divided into several smaller files. (There exists also a Windows 7 64bit version to handle larger files) The Pspcegrid30 program allows you to inspect individual spectra, extract these spectra in separate ASCII based spectroscopy files (either single files or all files) and to display 2d images out of the spectroscopy data.

File Format Specgrid

Format Specgrid File (Extension .Specgrid)

It starts with 1024 byte long header:

   version:                integer;
   nx,ny:                  integer;
   dx,dy:                  integer;
   specxgrid,specygrid:    integer;
   vertpoints:             integer;
   vertmandelay:           integer;
   vertmangain:            integer;
   biasvoltage:            single;
   tunnelcurrent:          single;
   imagedatasize:          integer;
   specgriddatasize:       integer;
   specgridchan:           integer;
   specgridchannelselectval:   integer;
   specgriddatasize64:       int64;
   xstart,xend,ystart,yend:  integer;
   dummy:  array[1..236] of integer;

Latest version is 4. Beginnng with version 4 you have xstart, xend which give you the specgrid line numbers. Ystart, Yend correspondingly. For older versions you have to calculate it:

 xend:=round(nx/specxgrid);
 yend:=round(ny/specygrid);
 xstart:=1;
 ystart:=1;

Specgridchan: Number of Channels in the Spectra. Specgridchannelselectval ist the bit pattern which detemines the type of selected channels. (Similar to vertchannelselectval) vertpoins: Number of points in a single spectrum.

After the header:

V and Z spectrum data: Each vertpoints long. 4byte floating point values.
V:  4 x vertpoints bytes for V
Z:  4 x vertpoints bytes for Z

After the V,Z data the spectra data are following in 4byte float format. Spectrum1 (X=1, Y=1), Number of channels: specgridchan*(vertpoints*4) byte for each spectrum grid point. Spectrum2 (X=2, Y=1), ........