[R] Adding comment in C++ code for debugging purpose

Rui Barradas ru|pb@rr@d@@ @end|ng |rom @@po@pt
Sat Dec 17 14:27:00 CET 2022


Às 11:05 de 17/12/2022, Christofer Bogaso escreveu:
> Hi Rui,
> 
> Unfortunately, the code Rcpp::Rcout << "---------->>>>>.My values" <<
> "\n"; still not printing the value.
> 
> Regarding your second suggestion, R_Print("My values\n"); - where
> should I put this statement?
> 
> On Sat, Dec 17, 2022 at 11:39 AM Rui Barradas <ruipbarradas using sapo.pt> wrote:
>>
>> Às 23:32 de 16/12/2022, Christofer Bogaso escreveu:
>>> Hi,
>>>
>>> I am using an R package where there are some C++ code.
>>>
>>> To check some intermediate values generated by that C++ code, I added
>>> a line like
>>>
>>> std::cout << "My values";
>>>
>>> Now with this modification, I next build a modified package (source) using
>>>
>>> R CMD build
>>>
>>> Next I install this modified package using install.packages() function
>>>
>>> However during the run-time of the C++ code with above modification, I
>>> dont get any print with "My values"
>>>
>>> Can you please help to understand why am not getting that printed?
>>>
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>>
>> Hello,
>>
>> If the package uses Rcpp try instead
>>
>>
>> Rcpp::Rcout << "My values" << "\n";   // or std::endl
>>
>>
>> More generally, there is also
>>
>>
>> R_Print("My values\n");
>>
>>
>>
>> Hope this helps,
>>
>> Rui Barradas
>>
>>
>>
>>

Hello,

Put R_Print where your cout is and instead of it.

As for Rcpp::Rcout, instead of "\n" try ending the line with std::endl 
to immediately flush the buffer.

Hope this helps,

Rui Barradas



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