The deadline is today. Sarthak
On Thu, Mar 24, 2016 at 1:52 AM, sarthak agarwal <sarthak0...@gmail.com> wrote: > Hello Dmitry, > > I fixed the bug (I guess). > Now coming to my proposal for GSoC, So I was thinking of working on > project #4 *Auto-detection of EPSG codes from incomplete WKT.* > > What I understood from the project is that we need to predict the EPSG > code of certain files on the basis of some attributes which are available > in the file. > > The attributes can be extracted from the file for which I read this > <http://www.gdal.org/osr_tutorial.html#querying_coordinate_system>. > > Now to solve this problem I thought a lot of methods but I think the best > way to solve it will be using machine learning. > > The way ML will handle this problem is as follows- > > 1. We need to find the EPSG code for a file (testing data) > 2. We have a file with some attributes (projections,datum,etc ). > 3. We need to the guess the best suitable class for that file(EPSG) > 4. Also, we have many files for which we know the attributes and the > corresponding class (training data). > > This problem is now translated into an ML problem which can be solved > using the following models- > > 1. Bayesian Stastics <https://en.wikipedia.org/wiki/Posterior_probability> > > where, > posteriror probability = probability of this file have EPSG code 'a'. > prior probability = probability of occurence of EPSG code 'a'. > > likelihood probablity = cases where we saw such attributes when the EPSG > code is 'a'. > > > 2. or we can use a simple knn where k is the number of possible EPSG code > and the dimension of the feature vector is the number of possible > attributes. we need to the find a valid and promising weight function). > > > 3. We can use multi-class SVM. > > 4. any other suggestion from the community regarding the possible choice > of the algo. > > I am thinking of actually implementing all these algo(may add algo in > future depending upon the suggestion) and select the algo which gives the > best performance among all of them. > > Please provide me feedback on my proposal and suggestion if I can > add/change anything. > And since very less time is left in the deadline, I would like to convert > it into proposal ASAP with your help. > > Regards, > Sarthak > > > On Tue, Mar 22, 2016 at 8:09 PM, sarthak agarwal <sarthak0...@gmail.com> > wrote: > >> Hello Dmitry, >> >> I have made all the necessary changes and now the code is working as >> expected ie If we provide no dbname, it will take the username by default. >> >> Here is the >> https://github.com/OSGeo/gdal/commit/417f4ed2642c56729f93fdb959e2bf1b9f1fdfb1 >> to >> the fix. >> >> Regards, >> Sarthak >> >> >> On Tue, Mar 22, 2016 at 1:49 AM, Dmitry Baryshnikov <bishop....@gmail.com >> > wrote: >> >>> Hi Sarthak, >>> >>> The problem is here >>> https://github.com/sarthak-0415/gdal/blob/trunk/gdal/frmts/postgisraster/postgisrasterdriver.cpp#L78 >>> >>> Your code produce situation there pszDbnameIn can be NULL. Before your >>> fixes, that cannot be. >>> So the line "CPLString osKey = pszDbnameIn;" produces crash. >>> >>> Don't wait for anybody with proposal. The new GSoC site is right place >>> to discuss proposals. >>> >>> Best regards, >>> Dmitry >>> >>> 20.03.2016 19:41, sarthak agarwal пишет: >>> >>> Hello to all, >>> >>> Sorry for taking too long (exams and travelling). >>> >>> After running few tests - >>> >>> - In my opinion, in Both the codes the error is not in >>> GetConnectionInfo function. if you replace return true with return >>> false at the last of the function it won’t fail in both cases. >>> - If you run this >>> >>> <https://github.com/sarthak-0415/gdal/commit/3e037a84e3392841cda1b4b68d75d205118caa9d> >>> and this >>> >>> <https://github.com/sarthak-0415/gdal/commit/26e9383645b177c9e4d2ca8798a3b662901f3b63> >>> code, it won’t give you the error, the value passed here are correct >>> (NULL >>> if that’s the case with *ppszDbname, the error is somewhere else and >>> I am not able to debug it.) >>> - When I am trying to configure the gdal with enable-debug options >>> following error comes >>> >>> make[1]: *** [gdalserver] Error 1 >>> make[1]: *** Waiting for unfinished jobs.... >>> /home/sarthak/gsoc2016/repos/gdal/gdal/.libs/libgdal.so: undefined >>> reference to `CPLMutexHolder::CPLMutexHolder(_CPLMutex**, double, char >>> const*, int, int)' >>> collect2: error: ld returned 1 exit status >>> >>> >>> My current config options are >>> ./configure --prefix=/home/sarthak/gsoc2016/repos/gdal/install/ >>> --with-python=yes -enabl-debug=yes >>> >>> the following error is for gdalServer gdalInfo gdal_translate and >>> gdaladdo. All are having the same problem with undefined reference to >>> `CPLMutexHolder::CPLMutexHolder(_CPLMutex**, double, char const*, int, int)' >>> >>> Please review the code and send me the feedback. >>> Also, I would like to continue with the bug along with my GSoC proposal. >>> For which I may have some ideas and would like to discuss the same with >>> you.. can we talk on IRC since the deadline is in 5 days only. >>> >>> Regards, >>> Sarthak >>> >>> On Wed, Mar 16, 2016 at 4:51 AM, Dmitry Baryshnikov < >>> bishop....@gmail.com> wrote: >>> >>>> Hi Sarthak, >>>> >>>> The first version is not working (do you test it?): >>>> <https://github.com/sarthak-0415/gdal/commit/36344cc26f23202cb289390322c1d295697136bd#diff-31df0e62d00ca09f9f11ad2f29e94b54R2541> >>>> https://github.com/sarthak-0415/gdal/commit/36344cc26f23202cb289390322c1d295697136bd#diff-31df0e62d00ca09f9f11ad2f29e94b54R2541 >>>> Here you try to get array value with index -1. You need to set ppszDbname >>>> = NULL no DB name present in input parameters. >>>> >>>> The second variant is not working too: >>>> >>> ds = gdal.Open('PG:') >>>> terminate called after throwing an instance of 'std::logic_error' >>>> what(): basic_string::_M_construct null not valid >>>> >>>> In both cases there is a problem here: >>>> <https://github.com/sarthak-0415/gdal/blob/6264d3fc52242fdce858547cc3a0312b04fd638b/gdal/frmts/postgisraster/postgisrasterdataset.cpp#L2743> >>>> https://github.com/sarthak-0415/gdal/blob/6264d3fc52242fdce858547cc3a0312b04fd638b/gdal/frmts/postgisraster/postgisrasterdataset.cpp#L2743 >>>> >>>> Also look there ppszDbname is using, as before modifications the code >>>> expect that ppszDbname cannot be NULL. >>>> >>>> Best regards, >>>> Dmitry >>>> >>>> 15.03.2016 13:13, sarthak agarwal пишет: >>>> >>>> Hey Dmitry , >>>> As discussed on the IRC yesterday, >>>> I made the changes in the code. >>>> >>>> I build two versions of the code >>>> >>>> 1. >>>> >>>> The changes suggested by you (to use the old trunk code and remove >>>> the additional checks) link >>>> >>>> <https://github.com/sarthak-0415/gdal/commit/36344cc26f23202cb289390322c1d295697136bd> >>>> travis <https://travis-ci.org/sarthak-0415/gdal/builds/116070409> . >>>> a. in this version the Dbname is left empty if not provided by the >>>> user. >>>> 2. >>>> >>>> The version in which we >>>> a. if the Dbname is provided by the user then ppzDbname=Dbname. >>>> b. else use the psql env var PGDATABASE >>>> c. else use the Username as the database name. >>>> d. if nothing is available then pass empty string. >>>> e link >>>> >>>> <https://github.com/sarthak-0415/gdal/commit/6264d3fc52242fdce858547cc3a0312b04fd638b> >>>> travis <https://travis-ci.org/sarthak-0415/gdal/builds/116055868> >>>> >>>> I think both version should work >>>> >>>> Regards, >>>> Sarthak >>>> >>>> >>> >>> >>> >> >
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