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x703jko
USA
5 Posts |
 Posted - 10/25/2004 : 12:24:12 PM
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Origin Version (Select Help-->About Origin): 7.5
Operating System: XP
Hi.
How do I get origin to report the width of a peak other than at the 50% point? (FWHM)
For example, how do I get it to report the 10% to 10% width. I know I can set baseline and use the cursor, but is there an automatic way for the software to present the result?
Thanks for reading and responding.
Jeff |
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easwar
USA
1964 Posts |
Posted - 10/25/2004 : 10:06:01 PM
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Hi Jeff,
Are you using the integrate command/menu item, or are you performing a fit with the gaussian function? If performing fit, you can add code to the After Fit script to compute relate parameters. For example, the Gaussian function by default reports the parameter w which is equal to 2 * sigma. Then FWHM will be 2*sqrt(2*ln(2))*sigma
and similarly an expression for 10% could be worked out and added to the after fit script for the Gaussian function.
Easwar
OriginLab
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khoa
1 Posts |
Posted - 05/04/2009 : 07:07:54 AM
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Hi,
we are having a similar problem, since we would like to determine the width of a fit at 10% maxmium. Unfortunately, our function is not a Gaussian function, but a inverse polynomial:
y=y0+A/(1 + A1*(2*(x-xc)/w)^2 + A2*(2*(x-xc)/w)^12)
We tried to compute
widthAtTenPercent = fwhm( x_y_curve, y0+0.1*A-0.9*A)
in the box derived parameters. However, x_y_curve is no longer a valid variable as in the paramter initialization and as a result the equation does not yield any result. Is there a way to use x_y_curve in both the parameter initialization and in derived parameters?
Thanks for any help. |
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Width of Distribution