ssa()

The simple scan analysis:

 
($ssa_status, $cms, $midpoint, $int, $bg_int, 
 $fwhm, $peak_x, $peak_y, $bg_l, $bg_r) = 
     Spectra::ssa( name => "ScanName", 
                   stbr => xval,       # optional                        
                   x_min => xval,      # optional
                   x_max => xval);     # optional

The meaning of the qualifiers:

stbr	The signal to background ratio. $ssa_status is zero, if the signal is not stbr times above the background.
x_min, x_max	The SSA is calculated for the points inside the specified limits.

The ssa() function returns:

$ssa_status	return status. $cms contains the reason, if $ssa_status == 0. Reason: 0: ok, 1: np < 6, 2: signal-to-background, 3: no y(i) > 0., 4, 5: midpoint calc, 6: max. outside x-range
$cms	center of mass
$midpoint	the midpoint between those points which are at 50% of the peak
$int	integral
$bg_int	integral of the background
$fwhm	full width half maximum
$peak_x	x-coord. of the highest point
$peak_y	y-coord. of the highest point
$bg_l	left background
$bg_r	right background