Hi there,

I am trying to run an MCMC on stable isotope data from certain organisms to
determine their dietary habits in the package SIAR.

I have prepared my data according to Inger, R., Jackson, A., Parnell, A.,
Bearhop, S. : SIAR V4 (Stable Isotope Analysis in R) an Ecologist's Guide
(also better known as 'SIAR for dummies'), which is as follows:

 - consumer data table (columns include code for species, d15N signatures,
d13C signatures)
-  source data table (columns include Source, mean d15N, SD d15N, Mean
d13C, SD d 13C)
-  trophic enrichment factor table (columns include source, mean15N, SD
d15N, mean d13C, SD d13C)

I've read the tables in as .txt ('data' for consumer data, 'sources' for
source data, and 'tef' for trophic enrichment factor) and tried to run the
MCMC as follows:

model1<-siarmcmcdirichletv4(data, sources, tef, concdep=0, 500000, 50000)

I keep receiving the following error warning:

'Error in siarmcmcdirichletv4(data, sources, tef, concdep = 0, 5e+05,
50000): NAs in foreign function call (arg 5)'


there aren't any NAs in my data set, so I assume that NAs are being created
by argument 5 in my code? I've tried to change the number for the
'burning', but then I get another error warning:

'Error in iterations, burning or thinby: (iterations-burnin)/thinby must be
an integer.'

What can I do to get the MCMC running?

thanks a lot for your help.

Best,

Claudia

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