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[Licence| Download | New Version Template] abac_v2_0.tar.gz(555 Kbytes)
Manuscript Title: VACTIV: a graphical dialog based program for an automatic processing of line and band spectra.
Authors: V.B. Zlokazov
Program title: VACTIV
Catalogue identifier: ABAC_v2_0
Distribution format: tar.gz
Journal reference: Comput. Phys. Commun. 184(2013)1480
Programming language: DELPHI 5-7 Pascal.
Computer: IBM PC series.
Operating system: Windows.
RAM: 1Mb
Keywords: Nuclear physics, Spectrum decomposition, Least squares analysis, Graphical dialog, Object-oriented programming.
Classification: 17.6.

Does the new version supersede the previous version?: Yes

Nature of problem:
Program VACTIV is intended for precise analysis of arbitrary spectrum-like distributions, e.g. gamma-ray and X-ray spectra and allows the user to carry out the full cycle of automatic processing of such spectra, i.e. calibration, automatic peak search and estimation of parameters of interest. VACTIV can run on any standard modern laptop.

Reasons for new version:
At the time of its creation (1999) VACTIV was seemingly the first attempt to apply the newest programming languages and styles to systems of spectrum analysis. Its goal was to both get a convenient and efficient technique for data processing, and to elaborate the formalism of spectrum analysis in terms of classes, their properties, their methods and events of an object-oriented programming language.

Summary of revisions:
Compared with ACTIV, VACTIV preserves all the mathematical algorithms, but provides the user with all the benefits of an interface, based on the graphical dialog.
It allows him to make a quick intervention in the work of the program; in particular, to carry out the on-line control of the fitting process: depending on the intermediate results and using the visual form of data representation, to change the conditions for the fitting and so achieve the optimum performance, selecting the optimum strategy.
To find the best conditions for the fitting one can compress the spectrum, delete the blunders from it, smooth it using a high-frequency spline filter and build the background using a low-frequency spline filter; use not only automatic methods for the blunder deletion, the peak search, the peak model forming and the calibration, but use also the manual mouse clicking on the spectrum graph.

To enhance the reliability and portability of the program the majority of the most important arrays have a static allocation; all the arrays are allocated with a surplus, and the total pool of the program is restricted only by the size of the computer virtual memory. A spectrum has the static size of 32K real words. The maximum size of the least-square matrix is 314 (the maximum number of fitted parameters per one analyzed spectrum interval, not for the whole spectrum), from which it follows that the maximum number of peaks in one spectrum interval is 154. The maximum total number of peaks in the spectrum is not restricted.

Running time:
The calculation time is negligibly small compared with the time for the dialog; using ini-files the program can be partly used in a semi-dialog mode.