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Search found 257 results on 11 pages for 'mat richardson'.

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  • C++ vs Matlab vs Python as a main language for Computer Vision Research

    - by Hough
    Hi all, Firstly, sorry for a somewhat long question but I think that many people are in the same situation as me and hopefully they can also gain some benefit from this. I'll be starting my PhD very soon which involves the fields of computer vision, pattern recognition and machine learning. Currently, I'm using opencv (2.1) C++ interface and I especially like its powerful Mat class and the overloaded operations available for matrix and image operations and seamless transformations. I've also tried (and implemented many small vision projects) using opencv python interface (new bindings; opencv 2.1) and I really enjoy python's ability to integrate opencv, numpy, scipy and matplotlib. But recently, I went back to opencv C++ interface because I felt that the official python new bindings were not stable enough and no overloaded operations are available for matrices and images, not to mention the lack of machine learning modules and slow speeds in certain operations. I've also used Matlab extensively in the past and although I've used mex files and other means to speed up the program, I just felt that Matlab's performance was inadequate for real-time vision tasks, be it for fast prototyping or not. When the project becomes larger and larger, many tasks have to be re-written in C and compiled into Mex files increasingly and Matlab becomes nothing more than a glue language. Here comes the sub-questions: For carrying out research in these fields (machine learning, vision, pattern recognition), what is your main or ideal programming language for rapid prototyping of ideas and testing algorithms contained in papers? For computer vision research work, can you list down the pros and cons of using the following languages? C++ (with opencv + gsl + svmlib + other libraries) vs Matlab (with all its toolboxes) vs python (with the imcomplete opencv bindings + numpy + scipy + matplotlib). Are there computer vision PhD/postgrad students here who are using only C++ (with all its availabe libraries including opencv) without even needing to resort to Matlab or python? In other words, given the current existing computer vision or machine learning libraries, is C++ alone sufficient for fast prototyping of ideas? If you're currently using Java or C# for your research, can you list down the reasons why they should be used and how they compare to other languages in terms of available libraries? What is the de facto vision/machine learning programming language and its associated libraries used in your research group? Thanks in advance. Edit: As suggested, I've opened the question to both academic and non-academic computer vision/machine learning/pattern recognition researchers and groups.

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  • Prolog: Sentence Parser Problem

    - by Devon
    Hey guys, Been sat here for hours now just staring at this code and have no idea what I'm doing wrong. I know what's happening from tracing the code through (it is going on an eternal loop when it hits verbPhrase). Any tips are more then welcome. Thank you. % Knowledge-base det(the). det(a). adjective(quick). adjective(brown). adjective(orange). adjective(sweet). noun(cat). noun(mat). noun(fox). noun(cucumber). noun(saw). noun(mother). noun(father). noun(family). noun(depression). prep(on). prep(with). verb(sat). verb(nibbled). verb(ran). verb(looked). verb(is). verb(has). % Sentece Structures sentence(Phrase) :- append(NounPhrase, VerbPhrase, Phrase), nounPhrase(NounPhrase), verbPhrase(VerbPhrase). sentence(Phrase) :- verbPhrase(Phrase). nounPhrase([]). nounPhrase([Head | Tail]) :- det(Head), nounPhrase2(Tail). nounPhrase(Phrase) :- nounPhrase2(Phrase). nounPhrase(Phrase) :- append(NP, PP, Phrase), nounPhrase(NP), prepPhrase(PP). nounPhrase2([]). nounPhrase2(Word) :- noun(Word). nounPhrase2([Head | Tail]) :- adjective(Head), nounPhrase2(Tail). prepPhrase([]). prepPhrase([Head | Tail]) :- prep(Head), nounPhrase(Tail). verbPhrase([]). verbPhrase(Word) :- verb(Word). verbPhrase([Head | Tail]) :- verb(Head), nounPhrase(Tail). verbPhrase(Phrase) :- append(VP, PP, Phrase), verbPhrase(VP), prepPhrase(PP).

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  • UpdatePanel Full Postback

    - by Korivo
    Greetings, here is the scenario. I have and .aspx page with and updatepanel like this <asp:UpdatePanel id="uPanelMain" runat="server"> <ContentTemplate> <uc:Calendar id="ucCalendar" runat="server" Visible="true" /> <uc:Scoring id="ucScoring" runat="server" Visible="false" /> </ContentTemplate> The control ucCalendar is loaded first and it contains a grid like this <asp:DataGrid CssClass="grid" ID="gridGames" runat="server" AutoGenerateColumns="False" HeaderStyle-CssClass="gridHeader" ItemStyle-CssClass="gridScoringRow" GridLines="None" ItemStyle-BackColor="#EEEEEE" AlternatingItemStyle-BackColor="#F5F5F5" OnEditCommand="doScoreGame" OnDeleteCommand="doEditGame" OnCancelCommand="printLineup" OnItemDataBound="gridDataBound"> <Columns> <asp:TemplateColumn > <ItemTemplate> <asp:CheckBox ID="chkDelete" runat="server" /> </ItemTemplate> </asp:TemplateColumn> <asp:BoundColumn DataField="idGame" Visible="false" /> <asp:BoundColumn DataField="isClose" Visible="false" /> <asp:TemplateColumn HeaderText="Status"> <ItemTemplate> <asp:Image ID="imgStatus" runat="server" ImageUrl="~/img/icoX.png" alt="icoStatus" /> </ItemTemplate> </asp:TemplateColumn> <asp:TemplateColumn> <ItemTemplate> <asp:LinkButton ID="linkScore" runat="server" CommandName="Edit" Text="Score" /> </ItemTemplate> </asp:TemplateColumn> </Columns> </asp:DataGrid> So when i click the "linkButton", the codebehind of the userControl calls a public method in the .aspx as this: From the userControl protected void doScoreGame(object sender, DataGridCommandEventArgs e) { ((GM)this.Page).showScoring(null, null); } From the .aspx page public void showScoring(object sender, EventArgs e) { removeLastLoadedControl(); ucScoring.Visible = true; } So, here comes the problem: There are two postbacks taking place when I change the visible attribute of the ucScoring control. The first postback is fine, it's handled by the updatePanel. The second postback is a full postback, and i really don't understand why it is happening. I'm really lost here, please help! Thanks Mat

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  • I am getting error when using Attributes in Rcpp and have RcppArmadillo code

    - by howard123
    I am trying to create a package with RcppArmadillo. The code uses the new attributes methodology of Rcpp. The sourceCpp works fine and compiles the code, but when I build a package I get errors when I use RcppArmadillo code. Without the RcppArmadillo code and using regulare C++, I do not get these errors. The C++ code (it is essentially the fastLm sample code) is: // [[Rcpp::depends(RcppArmadillo)]] #include <Rcpp.h> #include <RcppArmadillo.h> using namespace Rcpp; // [[Rcpp::depends(RcppArmadillo)]] #include <RcppArmadillo.h> // [[Rcpp::export]] List fastLm(NumericVector yr, NumericMatrix Xr) { int n = Xr.nrow(), k = Xr.ncol(); arma::mat X(Xr.begin(), n, k, false); arma::colvec y(yr.begin(), yr.size(), false); arma::colvec coef = arma::solve(X, y); arma::colvec resid = y - X*coef; double sig2 = arma::as_scalar(arma::trans(resid)*resid/(n-k)); arma::colvec stderrest = arma::sqrt( sig2 * arma::diagvec( arma::inv(arma::trans(X)*X)) ); return List::create(Named("coefficients") = coef, Named("stderr") = stderrest); } Here is the compilation error, after I execute "R Rcpp::compileAttributes() * Updated src/RcppExports.cpp == Rcmd.exe INSTALL --no-multiarch NewPackage * installing to library 'C:/Users/Howard/Documents/R/win-library/2.15' * installing *source* package 'NewPackage' ... ** libs g++ -m64 -I"C:/R/R-2-15-2/include" -DNDEBUG -I"C:/Users/Howard/Documents/R/win-library/2.15/Rcpp/include" -I"C:/Users/Howard/Documents/R/win-library/2.15/RcppArmadillo/include" -I"d:/RCompile/CRANpkg/extralibs64/local/include" -O2 -Wall -mtune=core2 -c RcppExports.cpp -o RcppExports.o g++ -m64 -I"C:/R/R-2-15-2/include" -DNDEBUG -I"C:/Users/Howard/Documents/R/win-library/2.15/Rcpp/include" -I"C:/Users/Howard/Documents/R/win-library/2.15/RcppArmadillo/include" -I"d:/RCompile/CRANpkg/extralibs64/local/include" -O2 -Wall -mtune=core2 -c test_arma3.cpp -o test_arma3.o g++ -m64 -shared -s -static-libgcc -o NewPackage.dll tmp.def RcppExports.o test_arma3.o C:/Users/Howard/Documents/R/win-library/2.15/Rcpp/lib/x64/libRcpp.a -Ld:/RCompile/CRANpkg/extralibs64/local/lib/x64 -Ld:/RCompile/CRANpkg/extralibs64/local/lib -LC:/R/R-2-15-2/bin/x64 -lR test_arma3.o:test_arma3.cpp:(.text+0xae4): undefined reference to `dgemm_' test_arma3.o:test_arma3.cpp:(.text+0x19db): undefined reference to `dgemm_' test_arma3.o:test_arma3.cpp:(.text+0x1b0c): undefined reference to `dgemv_' test_arma3.o:test_arma3.cpp:(.text$_ZN4arma6auxlib8solve_odIdNS_3MatIdEEEEbRNS2_IT_EES6_RKNS_4BaseIS4_T0_EE[_ZN4arma6auxlib8solve_odIdNS_3MatIdEEEEbRNS2_IT_EES6_RKNS_4BaseIS4_T0_EE]+0x702): undefined reference to `dgels_' test_arma3.o:test_arma3.cpp:(.text$_ZN4arma6auxlib8solve_udIdNS_3MatIdEEEEbRNS2_IT_EES6_RKNS_4BaseIS4_T0_EE[_ZN4arma6auxlib8solve_udIdNS_3MatIdEEEEbRNS2_IT_EES6_RKNS_4BaseIS4_T0_EE]+0x51c): undefined reference to `dgels_' test_arma3.o:test_arma3.cpp:(.text$_ZN4arma6auxlib10det_lapackIdEET_RKNS_3MatIS2_EEb[_ZN4arma6auxlib10det_lapackIdEET_RKNS_3MatIS2_EEb]+0x14b): undefined reference to `dgetrf_' test_arma3.o:test_arma3.cpp:(.text$_ZN4arma6auxlib5solveIdNS_3MatIdEEEEbRNS2_IT_EES6_RKNS_4BaseIS4_T0_EEb[_ZN4arma6auxlib5solveIdNS_3MatIdEEEEbRNS2_IT_EES6_RKNS_4BaseIS4_T0_EEb]+0x375): undefined reference to `dgesv_' test_arma3.o:test_arma3.cpp:(.text$_ZN4arma4gemvILb1ELb0ELb0EE15apply_blas_typeIdEEvPT_RKNS_3MatIS3_EEPKS3_S3_S3_[_ZN4arma4gemvILb1ELb0ELb0EE15apply_blas_typeIdEEvPT_RKNS_3MatIS3_EEPKS3_S3_S3_]+0x17d): undefined reference to `dgemv_' test_arma3.o:test_arma3.cpp:(.text$_ZN4arma27glue_times_redirect2_helperILb1EE5applyINS_2OpINS_3MatIdEENS_9op_htransEEES5_EEvRNS4_INT_9elem_typeEEERKNS_4GlueIS8_T0_NS_10glue_timesEEE[_ZN4arma27glue_times_redirect2_helperILb1EE5applyINS_2OpINS_3MatIdEENS_9op_htransEEES5_EEvRNS4_INT_9elem_typeEEERKNS_4GlueIS8_T0_NS_10glue_timesEEE]+0x37a): undefined reference to `dgemm_' test_arma3.o:test_arma3.cpp:(.text$_ZN4arma10op_diagvec5applyINS_2OpINS_4GlueINS2_INS_3MatIdEENS_9op_htransEEES5_NS_10glue_timesEEENS_6op_invEEEEEvRNS4_INT_9elem_typeEEERKNS2_ISC_S0_EE[_ZN4arma10op_diagvec5applyINS_2OpINS_4GlueINS2_INS_3MatIdEENS_9op_htransEEES5_NS_10glue_timesEEENS_6op_invEEEEEvRNS4_INT_9elem_typeEEERKNS2_ISC_S0_EE]+0x2c1): undefined reference to `dgetrf_' test_arma3.o:test_arma3.cpp:(.text$_ZN4arma10op_diagvec5applyINS_2OpINS_4GlueINS2_INS_3MatIdEENS_9op_htransEEES5_NS_10glue_timesEEENS_6op_invEEEEEvRNS4_INT_9elem_typeEEERKNS2_ISC_S0_EE[_ZN4arma10op_diagvec5applyINS_2OpINS_4GlueINS2_INS_3MatIdEENS_9op_htransEEES5_NS_10glue_timesEEENS_6op_invEEEEEvRNS4_INT_9elem_typeEEERKNS2_ISC_S0_EE]+0x322): undefined reference to `dgetri_' test_arma3.o:test_arma3.cpp:(.text$_ZN4arma10op_diagvec5applyINS_2OpINS_4GlueINS2_INS_3MatIdEENS_9op_htransEEES5_NS_10glue_timesEEENS_6op_invEEEEEvRNS4_INT_9elem_typeEEERKNS2_ISC_S0_EE[_ZN4arma10op_diagvec5applyINS_2OpINS_4GlueINS2_INS_3MatIdEENS_9op_htransEEES5_NS_10glue_timesEEENS_6op_invEEEEEvRNS4_INT_9elem_typeEEERKNS2_ISC_S0_EE]+0x398): undefined reference to `dgetri_' test_arma3.o:test_arma3.cpp:(.text$_ZN4arma10op_diagvec5applyINS_2OpINS_4GlueINS2_INS_3MatIdEENS_9op_htransEEES5_NS_10glue_timesEEENS_6op_invEEEEEvRNS4_INT_9elem_typeEEERKNS2_ISC_S0_EE[_ZN4arma10op_diagvec5applyINS_2OpINS_4GlueINS2_INS_3MatIdEENS_9op_htransEEES5_NS_10glue_timesEEENS_6op_invEEEEEvRNS4_INT_9elem_typeEEERKNS2_ISC_S0_EE]+0x775): undefined reference to `dgetrf_' test_arma3.o:test_arma3.cpp:(.text$_ZN4arma10op_diagvec5applyINS_2OpINS_4GlueINS2_INS_3MatIdEENS_9op_htransEEES5_NS_10glue_timesEEENS_6op_invEEEEEvRNS4_INT_9elem_typeEEERKNS2_ISC_S0_EE[_ZN4arma10op_diagvec5applyINS_2OpINS_4GlueINS2_INS_3MatIdEENS_9op_htransEEES5_NS_10glue_timesEEENS_6op_invEEEEEvRNS4_INT_9elem_typeEEERKNS2_ISC_S0_EE]+0x7d6): undefined reference to `dgetri_' test_arma3.o:test_arma3.cpp:(.text$_ZN4arma10op_diagvec5applyINS_2OpINS_4GlueINS2_INS_3MatIdEENS_9op_htransEEES5_NS_10glue_timesEEENS_6op_invEEEEEvRNS4_INT_9elem_typeEEERKNS2_ISC_S0_EE[_ZN4arma10op_diagvec5applyINS_2OpINS_4GlueINS2_INS_3MatIdEENS_9op_htransEEES5_NS_10glue_timesEEENS_6op_invEEEEEvRNS4_INT_9elem_typeEEERKNS2_ISC_S0_EE]+0x892): undefined reference to `dgetri_' collect2: ld returned 1 exit status ERROR: compilation failed for package 'NewPackage' * removing 'C:/Users/Howard/Documents/R/win-library/2.15/NewPackage' * restoring previous 'C:/Users/Howard/Documents/R/win-library/2.15/NewPackage' Exited with status 1.

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  • image processing algorithm in MATLAB

    - by user261002
    I am trying to reconstruct an algorithm belong to this paper: Decomposition of biospeckle images in temporary spectral bands Here is an explanation of the algorithm: We recorded a sequence of N successive speckle images with a sampling frequency fs. In this way it was possible to observe how a pixel evolves through the N images. That evolution can be treated as a time series and can be processed in the following way: Each signal corresponding to the evolution of every pixel was used as input to a bank of filters. The intensity values were previously divided by their temporal mean value to minimize local differences in reflectivity or illumination of the object. The maximum frequency that can be adequately analyzed is determined by the sampling theorem and s half of sampling frequency fs. The latter is set by the CCD camera, the size of the image, and the frame grabber. The bank of filters is outlined in Fig. 1. In our case, ten 5° order Butterworth11 filters were used, but this number can be varied according to the required discrimination. The bank was implemented in a computer using MATLAB software. We chose the Butter-worth filter because, in addition to its simplicity, it is maximally flat. Other filters, an infinite impulse response, or a finite impulse response could be used. By means of this bank of filters, ten corresponding signals of each filter of each temporary pixel evolution were obtained as output. Average energy Eb in each signal was then calculated: where pb(n) is the intensity of the filtered pixel in the nth image for filter b divided by its mean value and N is the total number of images. In this way, en values of energy for each pixel were obtained, each of hem belonging to one of the frequency bands in Fig. 1. With these values it is possible to build ten images of the active object, each one of which shows how much energy of time-varying speckle there is in a certain frequency band. False color assignment to the gray levels in the results would help in discrimination. and here is my MATLAB code base on that : clear all for i=0:39 str = num2str(i); str1 = strcat(str,'.mat'); load(str1); D{i+1}=A; end new_max = max(max(A)); new_min = min(min(A)); for i=20:180 for j=20:140 ts = []; for k=1:40 ts = [ts D{k}(i,j)]; %%% kth image pixel i,j --- ts is time series end ts = double(ts); temp = mean(ts); ts = ts-temp; ts = ts/temp; N = 5; % filter order W = [0.00001 0.05;0.05 0.1;0.1 0.15;0.15 0.20;0.20 0.25;0.25 0.30;0.30 0.35;0.35 0.40;0.40 0.45;0.45 0.50]; N1 = 5; for ind = 1:10 Wn = W(ind,:); [B,A] = butter(N1,Wn); ts_f(ind,:) = filter(B,A,ts); end for ind=1:10 imag_test1{ind}(i,j) =sum((ts_f(ind,:)./mean(ts_f(ind,:))).^2); end end end for i=1:10 temp_imag = imag_test1{i}(:,:); x=isnan(temp_imag); temp_imag(x)=0; temp_imag=medfilt2(temp_imag); t_max = max(max(temp_imag)); t_min = min(min(temp_imag)); temp_imag = (temp_imag-t_min).*(double(new_max-new_min)/double(t_max-t_min))+double(new_min); imag_test2{i}(:,:) = temp_imag; end for i=1:10 A=imag_test2{i}(:,:); B=A/max(max(A)); B=histeq(B); figure,imshow(B) colorbar end but I am not getting the same result as paper. has anybody has aby idea why? or where I have gone wrong? Refrence Link to the paper

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  • Sorting linked lists in Pascal

    - by user3712174
    I'm doing my final project for Informatics class and I can't get my sorting procedure to work. Have a look at my program, specifically the bolded part (some things are in Croatian. - if you need something translated, let me know): type pokazivac=^slog; slog=record prezime_ime:string[30]; redni_broj:string[2]; fakultet:string[50]; bodovi:integer; sljedeci:pokazivac; end; var pocetni, trenutni, prethodni:pokazivac; i:integer; procedure racunaj; var i,a,c:integer; b,d,e,f,g,h,j:real; begin write('Postotak bodova (u decimalnom zapisu) koje ucenik ostvaruje na temelju prosjeka ocjena - '); readln(e); e:=e*1000/4; write('Prosjek ocjena u prvom razredu : '); readln(f); f:=f/5*e; write('Prosjek ocjena u drugom razredu : '); readln(g); g:=g/5*e; write('Prosjek ocjena u trecem razredu : '); readln(h); h:=h/5*e; write('Prosjek ocjena u cetvrtom razredu : '); readln(j); j:=j/5*e; d:=f+g+h+j; write('Broj predmeta (ne racunajuci hrvatski jezik, strani jezik i matematiku) koju je ucenik/ca polagao na maturi - '); readln(a); write('Postotak rijesnosti ispita iz hrvatskog jezika te zatim maksimum bodova koje je ucenik/ca mogao ostvariti - '); readln(b); readln(c); d:=d+b*c; write('Postotak rijesnosti ispita iz stranog jezika te zatim maksimum bodova koje je ucenik/ca mogao ostvariti - '); readln(b); readln(c); d:=d+(b*c); write('Postotak rijesnosti ispita iz matematike te zatim maksimum bodova koje je ucenik/ca mogao ostvariti - '); readln(b); readln(c); d:=d+(b*c); for i:=1 to a do begin writeln('Postotak rijesnosti dodatnog predmeta te zatim maksimum bodova koje je ucenik/ca mogao ostvariti - '); readln(b); readln(c); d:=d+(b*c); end; d:=round(d); writeln('Vas broj bodova je: ', d:4:2); write('Za nastavak pritisnite ENTER..'); readln; end; procedure unos; begin new(trenutni); write('Redni broj ucenika - ');readln(trenutni^.redni_broj); write('Prezime i ime - ');readln(trenutni^.prezime_ime); write('Naziv fakultet - ');readln(trenutni^.fakultet); write('Bodovi - ');readln(trenutni^.bodovi); trenutni^.sljedeci:=pocetni; pocetni:=trenutni; end; procedure ispis; begin writeln(); writeln('Lista popisanih ucenika:'); writeln(); trenutni:=pocetni; while trenutni<>NIL do begin with trenutni^do begin writeln('IME: ',prezime_ime); writeln('FAKULTET: ',fakultet); writeln('BODOVI: ',bodovi); writeln(); end; trenutni:=trenutni^.sljedeci; end; writeln(); write('Za nastavak pritisnite ENTER..'); readln; end; procedure brisi; var s:string; begin trenutni:= pocetni; prethodni:=pocetni; write('Redni broj ucenika kojeg zelite izbrisati - '); readln(s); while trenutni<>NIL do begin if trenutni^.redni_broj=s then begin prethodni^.sljedeci:=trenutni^.sljedeci; dispose(trenutni); break; end; trenutni:=trenutni^.sljedeci; end; end; procedure izmjeni; var s:string; begin trenutni:=pocetni; write('Redni broj ucenika cije podatke zelite izmijeniti - '); readln(s); while trenutni<> NIL do begin if trenutni^.redni_broj=s then begin write(trenutni^.prezime_ime, ' - '); readln(trenutni^.prezime_ime); write(trenutni^.fakultet, ' - '); readln(trenutni^.fakultet); write(trenutni^.bodovi, ' - '); readln(trenutni^.bodovi); break; end; trenutni:=trenutni^.sljedeci; end; end; **procedure sortiraj; var t1,t2,t:pokazivac; begin t1:=pocetni; while t1 <> NIL do begin t2:=t1^.sljedeci; while t2<>NIL do if t2^.bodovi<t1^.bodovi then begin new(t); t^.redni_broj:=t1^.redni_broj; t^.prezime_ime:=t1^.prezime_ime; t^.fakultet:=t1^.fakultet; t^.bodovi:=t1^.bodovi; t1^.redni_broj:=t2^.redni_broj; t1^.prezime_ime:=t2^.prezime_ime; t1^.fakultet:=t2^.fakultet; t1^.bodovi:=t2^.bodovi; t2^.redni_broj:=t^.redni_broj; t2^.prezime_ime:=t^.prezime_ime; t2^.fakultet:=t^.fakultet; t2^.bodovi:=t^.bodovi; dispose(t); end; t2:=t2^.sljedeci; end; t1:=t1^.sljedeci; write('Za nastavak pritisnite ENTER..'); readln; end;** begin pocetni:=NIL; trenutni:=NIL; writeln('******************************************'); writeln('**********DOBRODOSLI U FAX-O-MAT**********'); writeln('******************************************'); repeat writeln('1 - Racunaj broj bodova'); writeln('2 - Dodaj ucenika'); writeln('3 - Brisi ucenika'); writeln('4 - Ispis liste'); writeln('5 - Izmjeni podatke'); writeln('6 - Sortiraj listu prema broju bodova'); writeln('0 - Kraj'); readln(i); case i of 1:racunaj; 2:unos; 3:brisi; 4:ispis; 5:izmjeni; 6:sortiraj; end; until i=0; end. Either it crashes with a fatal error, or when I press the number 6, nothing happens. The pointer keeps blinking and I can't enter any more numbers.

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  • Database Tutorial: The method open() is undefined for the type MainActivity.DBAdapter

    - by user2203633
    I am trying to do this database tutorial on SQLite Eclipse: https://www.youtube.com/watch?v=j-IV87qQ00M But I get a few errors at the end.. at db.ppen(); i get error: The method open() is undefined for the type MainActivity.DBAdapter and similar for insert record and close. MainActivity: package com.example.studentdatabase; import java.io.File; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import android.app.Activity; import android.app.ListActivity; import android.content.Intent; import android.database.Cursor; import android.os.Bundle; import android.util.Log; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.Button; import android.widget.Toast; public class MainActivity extends Activity { /** Called when the activity is first created. */ //DBAdapter db = new DBAdapter(this); @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); Button addBtn = (Button)findViewById(R.id.add); addBtn.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { Intent i = new Intent(MainActivity.this, addassignment.class); startActivity(i); } }); try { String destPath = "/data/data/" + getPackageName() + "/databases/AssignmentDB"; File f = new File(destPath); if (!f.exists()) { CopyDB( getBaseContext().getAssets().open("mydb"), new FileOutputStream(destPath)); } } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } DBAdapter db = new DBAdapter(); //---add an assignment--- db.open(); long id = db.insertRecord("Hello World", "2/18/2012", "DPR 224", "First Android Project"); id = db.insertRecord("Workbook Exercises", "3/1/2012", "MAT 100", "Do odd numbers"); db.close(); //---get all Records--- /* db.open(); Cursor c = db.getAllRecords(); if (c.moveToFirst()) { do { DisplayRecord(c); } while (c.moveToNext()); } db.close(); */ /* //---get a Record--- db.open(); Cursor c = db.getRecord(2); if (c.moveToFirst()) DisplayRecord(c); else Toast.makeText(this, "No Assignments found", Toast.LENGTH_LONG).show(); db.close(); */ //---update Record--- /* db.open(); if (db.updateRecord(1, "Hello Android", "2/19/2012", "DPR 224", "First Android Project")) Toast.makeText(this, "Update successful.", Toast.LENGTH_LONG).show(); else Toast.makeText(this, "Update failed.", Toast.LENGTH_LONG).show(); db.close(); */ /* //---delete a Record--- db.open(); if (db.deleteRecord(1)) Toast.makeText(this, "Delete successful.", Toast.LENGTH_LONG).show(); else Toast.makeText(this, "Delete failed.", Toast.LENGTH_LONG).show(); db.close(); */ } private class DBAdapter extends BaseAdapter { private LayoutInflater mInflater; //private ArrayList<> @Override public int getCount() { return 0; } @Override public Object getItem(int arg0) { return null; } @Override public long getItemId(int arg0) { return 0; } @Override public View getView(int arg0, View arg1, ViewGroup arg2) { return null; } } public void CopyDB(InputStream inputStream, OutputStream outputStream) throws IOException { //---copy 1K bytes at a time--- byte[] buffer = new byte[1024]; int length; while ((length = inputStream.read(buffer)) > 0) { outputStream.write(buffer, 0, length); } inputStream.close(); outputStream.close(); } public void DisplayRecord(Cursor c) { Toast.makeText(this, "id: " + c.getString(0) + "\n" + "Title: " + c.getString(1) + "\n" + "Due Date: " + c.getString(2), Toast.LENGTH_SHORT).show(); } public void addAssignment(View view) { Intent i = new Intent("com.pinchtapzoom.addassignment"); startActivity(i); Log.d("TAG", "Clicked"); } } DBAdapter code: package com.example.studentdatabase; public class DBAdapter { public static final String KEY_ROWID = "id"; public static final String KEY_TITLE = "title"; public static final String KEY_DUEDATE = "duedate"; public static final String KEY_COURSE = "course"; public static final String KEY_NOTES = "notes"; private static final String TAG = "DBAdapter"; private static final String DATABASE_NAME = "AssignmentsDB"; private static final String DATABASE_TABLE = "assignments"; private static final int DATABASE_VERSION = 2; private static final String DATABASE_CREATE = "create table if not exists assignments (id integer primary key autoincrement, " + "title VARCHAR not null, duedate date, course VARCHAR, notes VARCHAR );"; private final Context context; private DatabaseHelper DBHelper; private SQLiteDatabase db; public DBAdapter(Context ctx) { this.context = ctx; DBHelper = new DatabaseHelper(context); } private static class DatabaseHelper extends SQLiteOpenHelper { DatabaseHelper(Context context) { super(context, DATABASE_NAME, null, DATABASE_VERSION); } @Override public void onCreate(SQLiteDatabase db) { try { db.execSQL(DATABASE_CREATE); } catch (SQLException e) { e.printStackTrace(); } } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { Log.w(TAG, "Upgrading database from version " + oldVersion + " to " + newVersion + ", which will destroy all old data"); db.execSQL("DROP TABLE IF EXISTS contacts"); onCreate(db); } } //---opens the database--- public DBAdapter open() throws SQLException { db = DBHelper.getWritableDatabase(); return this; } //---closes the database--- public void close() { DBHelper.close(); } //---insert a record into the database--- public long insertRecord(String title, String duedate, String course, String notes) { ContentValues initialValues = new ContentValues(); initialValues.put(KEY_TITLE, title); initialValues.put(KEY_DUEDATE, duedate); initialValues.put(KEY_COURSE, course); initialValues.put(KEY_NOTES, notes); return db.insert(DATABASE_TABLE, null, initialValues); } //---deletes a particular record--- public boolean deleteContact(long rowId) { return db.delete(DATABASE_TABLE, KEY_ROWID + "=" + rowId, null) > 0; } //---retrieves all the records--- public Cursor getAllRecords() { return db.query(DATABASE_TABLE, new String[] {KEY_ROWID, KEY_TITLE, KEY_DUEDATE, KEY_COURSE, KEY_NOTES}, null, null, null, null, null); } //---retrieves a particular record--- public Cursor getRecord(long rowId) throws SQLException { Cursor mCursor = db.query(true, DATABASE_TABLE, new String[] {KEY_ROWID, KEY_TITLE, KEY_DUEDATE, KEY_COURSE, KEY_NOTES}, KEY_ROWID + "=" + rowId, null, null, null, null, null); if (mCursor != null) { mCursor.moveToFirst(); } return mCursor; } //---updates a record--- public boolean updateRecord(long rowId, String title, String duedate, String course, String notes) { ContentValues args = new ContentValues(); args.put(KEY_TITLE, title); args.put(KEY_DUEDATE, duedate); args.put(KEY_COURSE, course); args.put(KEY_NOTES, notes); return db.update(DATABASE_TABLE, args, KEY_ROWID + "=" + rowId, null) > 0; } } addassignment code: package com.example.studentdatabase; public class addassignment extends Activity { DBAdapter db = new DBAdapter(this); @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.add); } public void addAssignment(View v) { Log.d("test", "adding"); //get data from form EditText nameTxt = (EditText)findViewById(R.id.editTitle); EditText dateTxt = (EditText)findViewById(R.id.editDuedate); EditText courseTxt = (EditText)findViewById(R.id.editCourse); EditText notesTxt = (EditText)findViewById(R.id.editNotes); db.open(); long id = db.insertRecord(nameTxt.getText().toString(), dateTxt.getText().toString(), courseTxt.getText().toString(), notesTxt.getText().toString()); db.close(); nameTxt.setText(""); dateTxt.setText(""); courseTxt.setText(""); notesTxt.setText(""); Toast.makeText(addassignment.this,"Assignment Added", Toast.LENGTH_LONG).show(); } public void viewAssignments(View v) { Intent i = new Intent(this, MainActivity.class); startActivity(i); } } What is wrong here? Thanks in advance.

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