[R] catching errors in a loop

[Anders Bjørgesæter]

Hello

I can't figure out how to handle errors in R. I have a loop, e.g.

for (i in 2:n) {
.
fit <- nls(model), start=list

if any type of error occur write i to a text file
.
}

I putted “try” around the nls-expression and this let me run through the 
loop without R stopping (which I want because each loop takes some time so 
I do not want it to stop), but I also want to capture the variable when an 
error occur.

Appreciate any help

/Anders
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I tried to use:
**“options(error=write(variable.names(matrix[i]), 
file="..\\error.txt",append = TRUE))”, hoping this made R write to the text 
file every time an error occurred (but this made R write all i’s in the 
loop to the text file).
**tryCatch(<- nls(model), start=list
), finally =write(
) also writes to a 
text file but not necessary when there is an error.
**“if (Parameter>x errorM=9 else errorM =0” works but I want to capture any 
type of error.
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