New line reference system for errors seems confusing

Dear all,

Maybe I have missed something, but Stan started to inform me about the error with “wrong” line numbers which makes very difficult to debug. I think it’s been changed in one of the latest updates, because before that it worked perfectly.

For example, I have got the following mistake:

Exception: vector[uni] indexing: accessing element out of range. index 58 out of range; expecting index to be between 1 and 57 (in ‘…/Dropbox/XXX.stan’, line 563, column 12 to column 61)

but when I look at line 563, it is a part of the internal

    vector dLognorm(real param1, real param2, int K) {
        vector[K] res;
        for (k in 1:K)
            res[k] = lognormal_cdf(k - 0.5 | param1, param2); // here is the Line 563

        return append_row(res[1], tail(res, K-1) - head(res, K-1));  

Later I use the dLognorm in my generated quantities, and I think it causes the error.

As you can see, it is more difficult to say where the error had occurred (especially, if you use dLognorm function not once).

Have someone noticed something similar?


Thanks for reporting. Is this from an include? We used to print out the whole stack of include locations, but I’m not 100% sure what changed. @WardBrian should know.

It is difficult to say what may be occurring without seeing the full Stan code (It seems to be quite large, if line 563 is still inside the functions block?) and knowing which interface you are using

Hi all,

Thank you for your replies! After investigating for some time, I think the messages look reasonable - just at first, they seem out of place. Indeed I had a mistake in the boundaries, and I figure it out.

For example,

    array[K, Tmax] vector[D + 1] beta; // somewhere below I violate the second dimention with t > Tmax
    for (t in 1:Tmax+2)
        for (w in 1:K)
            beta[w, t] = dLognorm(param1_delay_ref[t] + log(K * omega[w]), param2_delay, D + 1); // (YYY)
    for (t in T-H+1:T) {
        vector[D+1] beta_current;
        for (d in 1:D+1) 
            beta_current[d] = t - d + 1 > 0 ? beta[omega_idx[t - d + 1, d], t - d + 1, d] : 0; // (XXX)
        beta_current /= sum(beta_current);

If I make a mistake in the very first line, such that the second dimension and t-d+1 would go above Tmax, Stan would point out either on line XXX or in the internal function dLognorm in YYY and in the declaration of dLognorm somewhere earlier in the code.

Of course, it takes time to find the source of the error and really point on the mistake in declaring the dimensions of beta.

Thank you again for your time!