baseline values not recognized

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Oct 15, 2018, 12:49:01 PM10/15/18
to tRophicPosition

quick question at a very beginning attempt to calculating trophic position for multiple species using only one baseline.

Any suggestion about what to do if the function extractIsotopeData just does not recognize my baseline, hence doesn't allow to initialize the model?

Here it is the function i run, which does not give errors apparently:

LowList <- extractIsotopeData(Low, b1 = "Baseline", b2 = NULL,
                                  baselineColumn = "FG", consumersColumn = "Spp",
                                  groupsColumn = "Community",
                                  d13C = "d13C", d15N = "d15N",
                                  deltaN = simulated_TDF$deltaN,
                                  deltaC = simulated_TDF$deltaC)

but here is an example of what i get when checking str(LowList ):

$ Diplo-Diplo:List of 6
  ..$ dNb1  : num(0) 
  ..$ dCb1  : num(0) 
  ..$ deltaN: num [1:15] 2.61 2.95  ...
  ..$ deltaC: num [1:15] 0.863 0.111  ...
  ..$ dNc   : num [1:2] 5.13 9.37
  ..$ dCc   : num [1:2] -20.2 -18.9

it's like if it doesn't recognize baseline values as numbers... or can it be related with the fact that i only have three values for the baseline? Is there a minimum of values the function requires to be recognized as baseline?

Thank you for any hint you can give me


Claudio Quezada R.

Oct 15, 2018, 1:14:27 PM10/15/18
to, tRophicPosition
Hi Cristina

What is the structure of Low? If the function is not recognizing baseline data, it might be related to the structure or the data of Low.

Could you send me the raw data?

There is no minimum number of observations of baselines. Certainly 3 observations is not enough, yet the model still will work.



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