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Next: Picking Properties for Trajectories Up: Power Spectrum Analysis Previous: Power Spectrum Analysis

Syntax

DYNAmics
ANALysis POWEr { $<$dynamics-power-statement$>$ } END is invoked from the main level of X-PLOR.
$<$dynamics-power-statement$>$ :==
$<$trajectory-statement$>$
defines the input data; see Section 12.1.3.
BACK=$<$logical$>$
performs Fourier back-transformation on power spectrum to obtain the vector autocorrelation function (default: FALSE).
\begin{displaymath} C(\tau)=<\vec{r}(t)*\vec{r}(t+\tau)> \end{displaymath} (12.2)

CLENgth=$<$realps$>$
provides length of correlation function in units of psec; it affects only the output file (default: 10).
COUTput=$<$filename$>$
writes the correlation function to the specified file.
PLENgth=$<$real$>$
provides the length of the power spectrum in units of psec$^{-1}$; it affects only the output file, not the calculation (default: 1000).
POUTput=$<$filename$>$
puts the power spectrum into the specified file.
POWER-2=$<$integer$>$
is an optional specification of a power of 2 for the FFT (default: 1).
PSKIp=$<$int$>$
is the skip value for the printout of the power spectrum. It does not affect the calculation. If pskip is zero, no power spectrum is written (default: 1).
TRIM=$<$logical$>$
trims the first (largest) peak from the power spectrum if TRIM is TRUE; if a correlation function is calculated later and the peak was at 0, this is equivalent to shifting the long time limit of the correlation function to 0 ( $\delta(0)\stackrel{FFT}{\rightarrow} \mbox{additive constant}$) (default: FALSE).
WINDow=( $<$real$>$ $<$real$>$ )
sets to zero everything in the power spectrum that is outside the window defined by the two values in units of psec$^{-1}$ (default: (0,1000)).
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Xplor-NIH 2024-09-13