[log in to unmask]" type="cite">
See answers below.
> -----Message d'origine-----
> De :
Stable Isotope Geochemistry[mailto:[log in to unmask]] De la part de
> Corentin Reutenauer
> Envoyé : 17 juin 2011 10:01
> À : [log in to unmask]
> Objet : Re: [ISOGEOCHEM] Delta value calculation
> Hi Jens,
> I have tried to duplicate isodat data as well (from dual inlet) and I am
> very close to get the exact result (change in the 7th decimal place of the
> delta value). It is not possible to change the significant numbers displayed
> for the "intensities" (3) in the results (.did files), but if you look at
> the plot below (on the same .did file), you can display a table with 6
> decimal places for the signal.
> However, I'd very much like to know what precision Isodat is using for
Isodat uses all the digits available in the computer to calculate everything. What you see is for display only.
> What I wonder is whether the impossibility to duplicate Isodat calculation
> is due to a lack of infomation on intensities, or due to the fact that there
> are different steps involved from intensity to delta value, and Isodat might
> round those numbers during the process (eg. delta1 and delta2 which are then
> averaged to get the "true" delta value)
Calculations of ratios are done on the areas not the intensities; unless you are talking about dual-inlet. If you want to see more digits (up to 15) then go to the Configurator/ Options/ Global Settings and adjust the digits you want to see under the "Value Formats". These settings will also export to Excel the full digits you specify here.
> Best regards,
-- Greg Michalski Assistant Professor Department of Earth and Atmosperic Sciences Purdue University http://www.purdue.edu/eas/michalski/