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Overlay a Curve Fit


The curve fit commands store the fit into the next higher overlay curve for the frame; e.g., if you read data into the first curve for a frame the fit is stored in the second. Curve fits are done after you read the data and are wiped out by the next read. The fit only uses the data within the x window.

does a linear fit. 

does a logrithmic fit. The following example does an exponential fit to the extended torus pressure (which has data for 80 seconds after t0).  

	Command[ ]? SH 55929  DE GS-PT-1S ;

Command[ ]? XT 10 80

Command[ ]? R SM F1 ,, !read and smooth a bit

Command[ ]? LE !exponential fit

Frame to fit[F1]? ,

[Fitting 876 points starting at 139]

Log Fit: Offset= 2.467E-07 Tau= 1.809E+01

Command[ ]? P !plot data and overlaid fit

does a polynominal fit. 

does a special sine wave fit that is appropriate for RP raw data.  

lists the line fit commands.

Marilee Thompson
Fri Jul 11 12:49:48 EDT 1997