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Tune Manual

6.0 - TUNE - Isotropic simulations & optimizations

The TUNE program optimizes the values of simulation parameters to produce a calculated spectrum with minimum residual error as compared to the experimental spectrum. The text input_file contains experimental, simulation, and parameter output filenames, optimization settings and starting simulation parameters. TUNE can either be used to produce a single simulation or an optimized simulation. TUNE also has the AUTO SIMULATE function. This is used to pick out potential simulations from a very large set of possibilities for a single isotropic EPR spectrum, particularly those which display a a complex pattern of many lines.


Usage:tune filename
Example:tune testdata.tun


The filename "testdata.tun" refers to an ASCII parameter file which contains all the information TUNE needs to execute. The format of this file is displayed later in this document. Information text will be printed to the screen until notification that the program has finished. You can then examine the output files for results. Creating the Input Files Create the parameter and spectrum input files. You can create the parameter file using either a text editor or by using functions functions provided by both the SimEPR and WinSIM programs. You will need both a parameter (.tun) file and an experimental spectrum file (.lmb, .exp, or .spc). For instance:


test01.tunASCII parameter file
test01.lmbbinary experimental spectrum data file


Now run the program as a command line program.


6.0.1 Format of the TUNE input file

The tune input-file is ASCII text and contains the following information: experimental file name, simulation file name, simulation parameters, optimization parameters. All letters may be either upper-case or lower-case. The order of the parameters is generally insignificant. All optimization flags are of the form 1= Optimize, 0= Remain Constant. An example:


Tune input file.unneeded title
----------------------------------------------------unneeded divider
F0: 0spectrum file types
F1: test01.lmbexperimental data file name
F2: test01.simsimulation data file name
F3: test01.eprtext parameter output file
----------------------------------------------------Unneeded divider
LMB fit parameters 
HF: 1Regular hcc analysis: 1= on, 0= off
PA: 0Parametric hcc analysis: 1= on, 0= off
ST: 0Step type: 0, 1, 2
NL: 7Number of levels of iteration
----------------------------------------------------Unneeded divider
Simplex fit parameters 
RS: 4Number of Restarts
IT: 600Max iterations per restart
TL: 0.01000Fractional Tolerance
----------------------------------------------------Unneeded divider
Continuous wave fit range 
DS: 1Data start, low data point of CW fit range
DE: 4096Data end, high data point of CW fit range
----------------------------------------------------Unneeded divider
Parameter constraints 
CHF: 0, 10hcc: flag, % deviation allowed
CLW: 0, 10linewidt: flag, % deviation allowed
CGS: 0, 10g-shift: flag, % deviation allowed
CRI: 0, 10intensity: flag, % deviation allowed
----------------------------------------------------Unneeded divider
Spectral parameters 
SM: 10=simple, 1=Nitroxide calculations
FT: 00=Continuous Wave, 1=Fourier
FF: 256FT combined frequency, unneeded if FT=0
HA: 1Harmonic: 0, 1, 2
MA: 1.333Modulation amplitude in Gauss
TC: 0.5ratio: time constant (ms) / scan time (s).
----------------------------------------------------Unneeded divider
SP: 1Species start identifier
LW: 0.100, 0LW value, optimization flag
LS: 6.000, 1Line shape value, opt. flag
RI: 118.000, 1Relative intensity, opt. flag
GS: -0.012, 1G-shift value, opt. flag
NX: 16.0, 1Nitroxide coupling
N1: 0.45, 1Nitroxide low field line width
N2: 0.55, 1Nitroxide mid field line width
N3: 0.65, 1Nitroxide high field line width
aa: 0.718, 0.5, 1, 1hcc value, spin, number, optimization flag
aa: 4.089, 0.5, 1, 1"
aa: 5.270, 0.5, 3, 1"
----------------------------------------------------unneeded divider
SP: 2species start identifier
LW: 0.100, 0
LS: 0.000, 1
RI: 50.000, 1
GS: -0.037, 1
NX: 13.5, 1
N1: 0.67, 1
N2: 0.72, 1
aa: 0.54, 0.5, 3, 1
aa: 4.75, 0.5, 3, 1
aa: 0.556, 0.5, 1, 1
same as above...


6.0.2 TUNE output

TUNE produces three output files, in our example:


test01.eprASCII text printout of simulation parameters
test01.outASCII parameter file which can again be used with TUNE
test01.simSimulation spectrum data file, same format as experimental data file


The text parameter output-file is a printout of the beginning and ending simulation parameters, SSR measurement, final Spearman's rank Correlation Coefficient, input and output filenames, and on the job time. This file can be read on screen or output to a printer, perhaps using the Reporter program. The simulation data output file can be loaded into the main EPR or WinSIM programs for viewing, comparing, and plotting.


6.1 - REPORTER - View and print text data files

This is a small Microsoft Windows program to view and edit text files with the .EPR suffix, normally the output of TUNE. In the MS-Windows properties box that accompanies each program icon, you should set the directory as the one most likely to contain these files. 


Conversion to HTML by DRD. Jan, 1996