SRS Labs SR430, Руководство пользователя

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Math Menu
Do Fit:
Line Exp.
Gauss.
Return:
Type of Fit
View
Left
Right
Limit:
Limit:
Params:
Abort Return
Type of Fit
MATH
Fit
View Parameters
Do Fit
Left Limit
Right Limit
Fit
The Fit sub menu allows the user to fit one of three curves to the dis-
played data: lines, exponentials, and Gaussians. Fitting is done using the
Marquardt 'Gradient-expansion' algorithm to minimize chi-squared.
Type of Fit
This function toggles the Type of Fit between line, exponential, and
Gaussian. The fit takes place only within the fit region defined by the Left
and Right Limits (see below).
Do Fit
Pressing this key starts the actual fitting calculations. As each pass of the
fitting routine progresses, the pass number and current value of chi-
squared is displayed. The algorithm is designed to terminate when the
change in chi-squared falls below 0.1%, although the fit may be terminat-
ed at any time by pressing the Abort key.
When the fit terminates, the best fit curve is plotted and the parameters
of the fit are displayed at the bottom of the screen. Pressing any key to
continue will restore the graph to normal. See View Parameters below for
a description of each fit.
View Parameters
The View Parameters function displays the most recent curve fit and pa-
rameters. For example, if a fit was performed and then the Fit menu exit-
ed, the fit will be erased from the screen. If the graph is then scaled dif-
ferently using the Display menu and then the Fit menu re-entered, the
curve fit is redrawn. The View Parameters function re-displays the pa-
rameters.
Both the Do Fit and View Parameters functions result in a display screen