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| PSEARCH.MAC | ||||||
| [ source code | installed at | configured at ] | ||||||
| See other macros in category: All | ||||||
Description:
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Documentation:
Psearch.mac is the spec front end to the psearch external program to search and fit peaks. The basic algorithm consists of removing first all peaks (above a certain statistical threshold), fitting a back ground function, isolating groups of peaks and trying to fit multipletts in an iterative procedure. The macros in this macro set are not directly used by the user, but provide the peak fitting to other macro sets. The macro set also provides the necessary functions to calibrate spectra in energy. The initial width estimation and the Energy-channel relation are: E=ea + eb ch + ec ch^2 ; FWHM = sqrt( wa^2 + wb E + (wc E)^2 ) EXAMPLE These example are not really meant to be typed in by the user. They should give you an example how to use the psearch function in your macros.
ps_calib
FWHM = sqr[a^2 + b*ch]
Term (a) in channels (5)?
Term (b) in channels (0.04)?
54 Peaks found
No Position Intensity FWHM Flag
1 51.284000 599.0 3.780 2
2 53.000000 368.0 3.645 2
......
8 232.835007 7014.0 8.290 3
9 248.266006 26738.0 6.822 3
....
No of 1. peak (9)?
Energy at peak 9, channel 248.266006 (Int:26738.0) (8.0441)?
No of 2. peak (54)?
Energy at peak 54, channel 3894.892090 (Int:1178503.0) (122.06)?
No of 3. peak (0 to end) (0)?
Linear FIT E= a + b*ch
CHI2: 0.000 ; a: 0.2817817 b: 0.03126613
Do you accept the fit (YES)?
The energy calibration is done. It is stored in the global
variables PS_EA , PS_EB, PS_EC. You can use the conversion
macros :
ps_calcch <Energy> <Channel>
ps_calcE <Channel> <Energy>
ps_Etoch group1 elem1 group2 elem2
ps_Etoch group1 elem1 group2 elem2
pssearch
Asks for initial width parameters and displays the peaks in
Energy.
SETUP The program psearch must be accessible. (in the path) ATTENTION make sure psearch is in the path DEPENDENCIES The file psearch.mac has to be read in !done by: startup script | ||||||
Macros:
Usage: pssearch (data arr, first channel, no data, wa, wb, wc, usee, minint, maxerror) Searches the current data array for peaks. The Energy calibration must have been done before. The result is put into PS_PEAKS. Can be used interactively by the user or from other macros with given width parameters. Only if called with no parameter it will produce output. The number of found peaks is stored in PS_NOPEAKS. ps_dump Usage: ps_dump Displays a long list of peaks found ps_sdump Usage: ps_sdump Displays a short list of peaks found ps_show Usage: ps_show Displays the calibration parameters, number of peaks and a short list of the last found peaks. ps_calib Usage: ps_calib (data, firstch, nodata) Does a peaksearch on array data. Then asks the user for calibration energy of some peaks and fits a linear or quadratic function. ps_parinput Usage: ps_parinput Shows the calibration parameters and lets the user change them ps_calcE Usage: ps_calcE <Channel> <Energy> Converts from Energy to channel (channel to Energy). The first parameter is the value to convert and the second parameter a variable name where to put the converted value. ps_calcch Usage: ps_calcch (Energy) return the corresponding channel. Suppose that there is only a small quadratic correction ps_chtoE Usage: ps_chtoE (channel array, Energy array) Converts all the channels in source array[][column1] to energies and puts these values into destination array[][column2]. The calibration function E=a+b ch + c ch^2 is used. ps_Etoch Usage: ps_Etoch (Energy array, channel array) Converts all the energies in sorce array[][column1] to channels and puts these values into destination array[][column2]. The taylor expansion for the parabolic calibration function E=a+b ch + c ch^2 is used. pssetup Usage: pssetup defines the global variables and looks for psearch executable | ||||||
| Internal Macros: | ||||||
Usage: old_array_pipe (program , arguments , array_in, array_out) like data_pipe but for arrays. This This needs the new version of the binary program psearch!!!!! Please update this program. _obsolete_array_pipe Usage: _obsolete_array_pipe(program , arguments , array_in, array_out,nodata) ps_psearch Usage: ps_psearch (data, data_col, minch, no, a, b, c, wa, wb, wc) Does the peak search for the array given in data. The data holds only counts. The corresponding channel numbers go from minch to minch + no - 1. The a, b and c parameters provide means to input an enery calibration (E = a + b * ch + c * ch * ch). The routine needs an estimate for the peak width. The parameters for this estimate are given by W(E) = sqrt (wa**2 + wb*E + (wc*E)**2). The results will be in the global array PS_PEAKS. The individual columns are: No Channel Counts FWHM Flag Energy FWHM-E. The calculation will always be done in channels, only the width parameters will be ajusted for the given calibration. ps_reject Usage: ps_reject ( minint, wa, wb, wc, %error, minE, maxE ) FWHM = sqr[wa^2 + wb*E + (wc*E)^2] Deletes all peaks from the PS_PEAKS which do not fullfill the given conditions ps_testdata Usage: ps_testdata ps_calibration Usage: ps_calibration see ps_calib ps_ofit Usage: ps_ofit(ya,xa,no,order,verbose) Same functionality as ps_fit but for old type arrays ps_fit Usage: ps_fit (y, x, no of data points, order, verbose flag) Do a linear or quadratic fit y = a + b * x + c * x**2. The (a,b,c) parameters are returned in the global array PS_PAR. The return value of the function is the chi2 of the fit. If the verbose flag is set, the fitvalues are printed to the screen. | ||||||
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