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Posted to dev@madlib.apache.org by Babak Alipour <ba...@gmail.com> on 2016/02/19 03:34:28 UTC
Hello World Example Errors
Greetings everyone,
I am Babak Alipour, a student at University of Florida. I have been trying
to use MADlib and I hope to contribute to the community later on.
While trying to go through the quick start guide for developers (available
here :
https://cwiki.apache.org/confluence/display/MADLIB/Quick+Start+Guide+for+Developers),
I realized that in avg_var.cpp there are some lines that use 'this.member'.
I think 'this' is a pointer and it should be used with '->'.
So I tried to build MADlib from source with these files added, and it
doesn't.
It produces multiple compile-time errors:
E.g. ' error: request for member ‘avg’ in ‘this’, which is of pointer type
...'
Replacing every 'this.' with 'this->' takes care of those errors but there
are still a few more errors in the given example.
Line 53:
double a = static_cast<double>(state.numRows) / normalizer;
Produces an error, since 'state' is not defined in this scope. Since this
function is overloading '+=', I think it's safe to say this was supposed to
be the state of 'this', so I replaced it with 'this->' and that error went
away.
Lines 44 & 45:
template <class OtherHandle>
AvgVarTransitionState &operator+=(const double x){
This was also producing compile errors. (failed to deduce OtherHandle
template type) This takes a double and adds it to the state, so I don't see
any uses for 'OtherHandle' in this context and I commented line 44.
All said and done, MADlib now compiles, installs and works just fine.
I was wondering if anyone else encountered these issues while going through
the hello world example.
I could fork the project, fix the example and submit a pull-request if you
think that's the way to go.
Best regards,
*Babak Alipour ,*
*University of Florida*
Re: Hello World Example Errors
Posted by Greg Chase <gr...@gregchase.com>.
Babak - do you mind filing a Jira at
https://issues.apache.org/jira/browse/MADLIB/?selectedTab=com.atlassian.jira.jira-projects-plugin:summary-panel
Might as well score yourself some Karma with the project :)
-Greg
On Fri, Feb 19, 2016 at 11:40 AM, Orhan Kislal <ok...@pivotal.io> wrote:
> Hello Babak,
>
> Thanks for pointing out these errors. I remember making changes to the
> hello world examples when I first started as well. I suggest making a pull
> request with your updated files (as you noted) so that the next developer
> does not get confused with the same bugs. Here is the website for
> contribution guidelines:
> https://cwiki.apache.org/confluence/display/MADLIB/Contribution+Guidelines
> Since you are interested in contributing to MADlib, I would suggest
> checking the following link as well for contribution ideas.
> https://cwiki.apache.org/confluence/display/MADLIB/Ideas+for+Contribution
>
> Best Regards,
>
> Orhan Kislal
>
>
> On Thu, Feb 18, 2016 at 6:34 PM, Babak Alipour <ba...@gmail.com>
> wrote:
>
> > Greetings everyone,
> >
> > I am Babak Alipour, a student at University of Florida. I have been
> trying
> > to use MADlib and I hope to contribute to the community later on.
> >
> > While trying to go through the quick start guide for developers
> (available
> > here :
> >
> >
> https://cwiki.apache.org/confluence/display/MADLIB/Quick+Start+Guide+for+Developers
> > ),
> > I realized that in avg_var.cpp there are some lines that use
> 'this.member'.
> > I think 'this' is a pointer and it should be used with '->'.
> > So I tried to build MADlib from source with these files added, and it
> > doesn't.
> > It produces multiple compile-time errors:
> > E.g. ' error: request for member ‘avg’ in ‘this’, which is of pointer
> type
> > ...'
> >
> > Replacing every 'this.' with 'this->' takes care of those errors but
> there
> > are still a few more errors in the given example.
> >
> > Line 53:
> > double a = static_cast<double>(state.numRows) / normalizer;
> > Produces an error, since 'state' is not defined in this scope. Since this
> > function is overloading '+=', I think it's safe to say this was supposed
> to
> > be the state of 'this', so I replaced it with 'this->' and that error
> went
> > away.
> >
> > Lines 44 & 45:
> > template <class OtherHandle>
> > AvgVarTransitionState &operator+=(const double x){
> >
> > This was also producing compile errors. (failed to deduce OtherHandle
> > template type) This takes a double and adds it to the state, so I don't
> see
> > any uses for 'OtherHandle' in this context and I commented line 44.
> >
> > All said and done, MADlib now compiles, installs and works just fine.
> >
> > I was wondering if anyone else encountered these issues while going
> through
> > the hello world example.
> >
> > I could fork the project, fix the example and submit a pull-request if
> you
> > think that's the way to go.
> >
> >
> > Best regards,
> > *Babak Alipour ,*
> > *University of Florida*
> >
>
Re: Hello World Example Errors
Posted by Orhan Kislal <ok...@pivotal.io>.
Hello Babak,
Thanks for pointing out these errors. I remember making changes to the
hello world examples when I first started as well. I suggest making a pull
request with your updated files (as you noted) so that the next developer
does not get confused with the same bugs. Here is the website for
contribution guidelines:
https://cwiki.apache.org/confluence/display/MADLIB/Contribution+Guidelines
Since you are interested in contributing to MADlib, I would suggest
checking the following link as well for contribution ideas.
https://cwiki.apache.org/confluence/display/MADLIB/Ideas+for+Contribution
Best Regards,
Orhan Kislal
On Thu, Feb 18, 2016 at 6:34 PM, Babak Alipour <ba...@gmail.com>
wrote:
> Greetings everyone,
>
> I am Babak Alipour, a student at University of Florida. I have been trying
> to use MADlib and I hope to contribute to the community later on.
>
> While trying to go through the quick start guide for developers (available
> here :
>
> https://cwiki.apache.org/confluence/display/MADLIB/Quick+Start+Guide+for+Developers
> ),
> I realized that in avg_var.cpp there are some lines that use 'this.member'.
> I think 'this' is a pointer and it should be used with '->'.
> So I tried to build MADlib from source with these files added, and it
> doesn't.
> It produces multiple compile-time errors:
> E.g. ' error: request for member ‘avg’ in ‘this’, which is of pointer type
> ...'
>
> Replacing every 'this.' with 'this->' takes care of those errors but there
> are still a few more errors in the given example.
>
> Line 53:
> double a = static_cast<double>(state.numRows) / normalizer;
> Produces an error, since 'state' is not defined in this scope. Since this
> function is overloading '+=', I think it's safe to say this was supposed to
> be the state of 'this', so I replaced it with 'this->' and that error went
> away.
>
> Lines 44 & 45:
> template <class OtherHandle>
> AvgVarTransitionState &operator+=(const double x){
>
> This was also producing compile errors. (failed to deduce OtherHandle
> template type) This takes a double and adds it to the state, so I don't see
> any uses for 'OtherHandle' in this context and I commented line 44.
>
> All said and done, MADlib now compiles, installs and works just fine.
>
> I was wondering if anyone else encountered these issues while going through
> the hello world example.
>
> I could fork the project, fix the example and submit a pull-request if you
> think that's the way to go.
>
>
> Best regards,
> *Babak Alipour ,*
> *University of Florida*
>