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Showing numbers in decimal not scientific notation

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  • tomyT tomy

    @Chris-Kawa said in Showing numbers in decimal not scientific notation:

    QString s;
    QTextStream (&s) << QString::number(12.0, 'f');
    lineEdit -> setText(s);
    

    I used it. It's fine for doubles but when I calculate ints (e.g., 2+3) it shows 5.000000!!
    We should make it show the precision only when the result is a double number not an int.

    kshegunovK Offline
    kshegunovK Offline
    kshegunov
    Moderators
    wrote on last edited by kshegunov
    #15

    @tomy said in Showing numbers in decimal not scientific notation:

    I used it. It's fine for doubles but when I calculate ints (e.g., 2+3) it shows 5.000000!!
    We should make it show the precision only when the result is a double number not an int.

    You either calculate a double or an int, can't be both. Anyway, what you probably want is this:

    double calculationResult = 12.0;
    QString displayValue = qFuzzyCompare(calculationResult, static_cast<qint64>(calculationResult)) ? QString::number(static_cast<qint64>(calculationResult)) : QString::number(calculationResult, 'f');
    

    Read and abide by the Qt Code of Conduct

    tomyT 1 Reply Last reply
    1
    • kshegunovK kshegunov

      @tomy said in Showing numbers in decimal not scientific notation:

      I used it. It's fine for doubles but when I calculate ints (e.g., 2+3) it shows 5.000000!!
      We should make it show the precision only when the result is a double number not an int.

      You either calculate a double or an int, can't be both. Anyway, what you probably want is this:

      double calculationResult = 12.0;
      QString displayValue = qFuzzyCompare(calculationResult, static_cast<qint64>(calculationResult)) ? QString::number(static_cast<qint64>(calculationResult)) : QString::number(calculationResult, 'f');
      
      tomyT Offline
      tomyT Offline
      tomy
      wrote on last edited by tomy
      #16

      @kshegunov

      You either calculate a double or an int, can't be both.
      Anyway, what you probably want is this:

      How can it be acceptable!? All calculator around the world do calculations on both types. Furthermore, when I write 2.3+4.6, it shows: 6.900000!
      That is it works fine neither for ints nor for doubles.

      double calculationResult = 12.0;
      QString displayValue = qFuzzyCompare(calculationResult, static_cast<qint64>(calculationResult) ? QString::number(static_cast<qint64>(calculationResult)) : QString::number(calculationResult, 'f');
      

      Ow my God! Isn't there any simpler way?
      Please have a look at Windows built-in calculator. See this how simple and nifty shows results.
      Do you say that behind that Windows' calculator there would be such a long statement just for showing numbers in decimal mode, if it were written by C++/Qt?

      kshegunovK VRoninV 2 Replies Last reply
      0
      • tomyT tomy

        @kshegunov

        You either calculate a double or an int, can't be both.
        Anyway, what you probably want is this:

        How can it be acceptable!? All calculator around the world do calculations on both types. Furthermore, when I write 2.3+4.6, it shows: 6.900000!
        That is it works fine neither for ints nor for doubles.

        double calculationResult = 12.0;
        QString displayValue = qFuzzyCompare(calculationResult, static_cast<qint64>(calculationResult) ? QString::number(static_cast<qint64>(calculationResult)) : QString::number(calculationResult, 'f');
        

        Ow my God! Isn't there any simpler way?
        Please have a look at Windows built-in calculator. See this how simple and nifty shows results.
        Do you say that behind that Windows' calculator there would be such a long statement just for showing numbers in decimal mode, if it were written by C++/Qt?

        kshegunovK Offline
        kshegunovK Offline
        kshegunov
        Moderators
        wrote on last edited by kshegunov
        #17

        @tomy said in Showing numbers in decimal not scientific notation:

        How can it be acceptable!? All calculator around the world do calculations on both types. Furthermore, when I write 2.3+4.6, it shows: 6.900000!

        No they do calculation in the widest possible type they support (here it's double) and then display the result as appropriate. Further reading on implicit type promotions in c++ can be found here

        Ow my God! Isn't there any simpler way?

        This is a simple if-else statement with the notable exception that it compares floating point values as they should be compared.

        Do you say that behind that Windows' calculator there would be such a long statement just for showing numbers in decimal mode, if it were written by C++/Qt?

        Yes, I'm sure of it. It's probably even much longer as windows is actually written in C.

        Read and abide by the Qt Code of Conduct

        1 Reply Last reply
        1
        • tomyT Offline
          tomyT Offline
          tomy
          wrote on last edited by tomy
          #18

          I used this:

          ss = qFuzzyCompare(expression(),
                           static_cast<qint64>(expression()) ?
                           QString::number(static_cast<qint64>(expression())) :
                           QString::number(expression(), 'f'));
           result_box -> setText(ss);
          

          ss is a QString.
          expression() returns an int or double value.
          result_box is a lineEdit which shows the result of the calculations.

          I get this error:
          C:\Users\ME\Documents\Qt\My_First_Calculator\my_first_calculator.cpp:81: error: no matching function for call to 'qFuzzyCompare(double, QString)'
          QString::number(expression(), 'f'));
          ^

          kshegunovK 1 Reply Last reply
          0
          • tomyT tomy

            I used this:

            ss = qFuzzyCompare(expression(),
                             static_cast<qint64>(expression()) ?
                             QString::number(static_cast<qint64>(expression())) :
                             QString::number(expression(), 'f'));
             result_box -> setText(ss);
            

            ss is a QString.
            expression() returns an int or double value.
            result_box is a lineEdit which shows the result of the calculations.

            I get this error:
            C:\Users\ME\Documents\Qt\My_First_Calculator\my_first_calculator.cpp:81: error: no matching function for call to 'qFuzzyCompare(double, QString)'
            QString::number(expression(), 'f'));
            ^

            kshegunovK Offline
            kshegunovK Offline
            kshegunov
            Moderators
            wrote on last edited by
            #19

            @tomy said in Showing numbers in decimal not scientific notation:

            expression() returns an int or double value.

            I'm pretty sure that functions returns a string, not an int, nor a double. You need to convert the string to an actual number if you want to use it as such, e.g. see here.

            Read and abide by the Qt Code of Conduct

            tomyT 1 Reply Last reply
            0
            • kshegunovK kshegunov

              @tomy said in Showing numbers in decimal not scientific notation:

              expression() returns an int or double value.

              I'm pretty sure that functions returns a string, not an int, nor a double. You need to convert the string to an actual number if you want to use it as such, e.g. see here.

              tomyT Offline
              tomyT Offline
              tomy
              wrote on last edited by tomy
              #20

              @kshegunov

              expression() returns an int or double value.

              I'm pretty sure that functions returns a string, not an int, nor a double.

              Don't be that sure. :)
              I have this method in my code:

              double My_First_Calculator::expression()
              

              But I think this error is of that ss is a QString.

              kshegunovK 1 Reply Last reply
              0
              • tomyT tomy

                @kshegunov

                You either calculate a double or an int, can't be both.
                Anyway, what you probably want is this:

                How can it be acceptable!? All calculator around the world do calculations on both types. Furthermore, when I write 2.3+4.6, it shows: 6.900000!
                That is it works fine neither for ints nor for doubles.

                double calculationResult = 12.0;
                QString displayValue = qFuzzyCompare(calculationResult, static_cast<qint64>(calculationResult) ? QString::number(static_cast<qint64>(calculationResult)) : QString::number(calculationResult, 'f');
                

                Ow my God! Isn't there any simpler way?
                Please have a look at Windows built-in calculator. See this how simple and nifty shows results.
                Do you say that behind that Windows' calculator there would be such a long statement just for showing numbers in decimal mode, if it were written by C++/Qt?

                VRoninV Offline
                VRoninV Offline
                VRonin
                wrote on last edited by
                #21

                @tomy Did you even try my solution?

                "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
                ~Napoleon Bonaparte

                On a crusade to banish setIndexWidget() from the holy land of Qt

                tomyT 1 Reply Last reply
                0
                • VRoninV VRonin

                  @tomy Did you even try my solution?

                  tomyT Offline
                  tomyT Offline
                  tomy
                  wrote on last edited by
                  #22

                  @VRonin

                  Should I use it this way:

                  QString ss;
                  ss = result_box -> locale().toString(1257.147862,'f');
                  QTextStream (&ss) << expression();
                  result_box -> setText(ss);
                  

                  ?

                  VRoninV 1 Reply Last reply
                  0
                  • tomyT tomy

                    @VRonin

                    Should I use it this way:

                    QString ss;
                    ss = result_box -> locale().toString(1257.147862,'f');
                    QTextStream (&ss) << expression();
                    result_box -> setText(ss);
                    

                    ?

                    VRoninV Offline
                    VRoninV Offline
                    VRonin
                    wrote on last edited by
                    #23

                    @tomy No, don't use QTextStream you don't need something like stringstream to pass numbers to string.

                    QString ss;
                    ss = result_box -> locale().toString(expression(),'f');
                    result_box -> setText(ss);
                    

                    or more concisely, result_box->setText(result_box->locale().toString(expression(),'f'));

                    "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
                    ~Napoleon Bonaparte

                    On a crusade to banish setIndexWidget() from the holy land of Qt

                    tomyT 1 Reply Last reply
                    0
                    • VRoninV VRonin

                      @tomy No, don't use QTextStream you don't need something like stringstream to pass numbers to string.

                      QString ss;
                      ss = result_box -> locale().toString(expression(),'f');
                      result_box -> setText(ss);
                      

                      or more concisely, result_box->setText(result_box->locale().toString(expression(),'f'));

                      tomyT Offline
                      tomyT Offline
                      tomy
                      wrote on last edited by
                      #24

                      @VRonin said in Showing numbers in decimal not scientific notation:

                      @tomy No, don't use QTextStream you don't need something like stringstream to pass numbers to string.

                      QString ss;
                      ss = result_box -> locale().toString(expression(),'f');
                      result_box -> setText(ss);
                      

                      I used it. 2 + 3 = 5.000000 :( :(

                      1 Reply Last reply
                      0
                      • VRoninV Offline
                        VRoninV Offline
                        VRonin
                        wrote on last edited by
                        #25

                        what is result_box and what is inside expression()?

                        "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
                        ~Napoleon Bonaparte

                        On a crusade to banish setIndexWidget() from the holy land of Qt

                        tomyT 1 Reply Last reply
                        0
                        • VRoninV VRonin

                          what is result_box and what is inside expression()?

                          tomyT Offline
                          tomyT Offline
                          tomy
                          wrote on last edited by tomy
                          #26

                          @VRonin

                          what is result_box

                          It's a lineEdit.

                          and what is inside expression()?

                          It returns only a double value. Consider something simple like:

                          double My_First_Calculator::expression()
                          {
                             double d1, d2;    // these d1, d2 are gotten from input E.g. d1 = 2, d2 = 3.5
                            if(_ch == '+') return d1+d2;  // _ch is a previously defined varible 
                           else if (_ch == '-') return d1-d2;  // and so on
                          }
                          
                          1 Reply Last reply
                          0
                          • tomyT Offline
                            tomyT Offline
                            tomy
                            wrote on last edited by tomy
                            #27

                            I simplified the code as follows. This, too, has exactly that problem:

                            test.h

                            #ifndef TEST_H
                            #define TEST_H
                            #include <QDialog>
                            
                            class QLineEdit;
                            class QPushButton;
                            
                            class test : public QDialog
                            {
                                Q_OBJECT
                            public:
                                test(QWidget* parent = 0);
                            
                            private slots:
                                void expression();
                            
                            private:
                                QLineEdit* result_box;
                                QPushButton* equal;
                                QPushButton* quit;
                            };
                            
                            #endif // TEST_H
                            

                            test.cpp

                            #include <QtWidgets>
                            #include "test.h"
                            
                            test::test(QWidget* parent) : QDialog(parent)
                            {
                              result_box = new QLineEdit;
                              equal = new QPushButton(tr("="));
                              quit = new QPushButton(tr("Close"));
                            
                            
                              connect(quit, SIGNAL(clicked(bool)), this, SLOT(close()));
                              connect(equal,SIGNAL(clicked(bool)), this, SLOT(expression()));
                            
                              QHBoxLayout* layout = new QHBoxLayout;
                              layout -> addWidget(result_box);
                              layout -> addWidget(equal);
                              layout -> addWidget(quit);
                            
                              setLayout(layout);
                            }
                            
                            //******************
                            
                            void test::expression()
                            {
                                QString ss;
                                double d = 1000000;
                                QTextStream (&ss) << d;
                                result_box -> setText(ss);
                            }
                            

                            And main.cpp

                            #include <QApplication>
                            #include "test.h"
                            
                            int main(int argc, char* argv[])
                            {
                                QApplication app(argc, argv);
                                test t;
                                t.show();
                            
                               return app.exec();
                            }
                            

                            Just run it and click on the = button.

                            tomyT 1 Reply Last reply
                            0
                            • tomyT tomy

                              I simplified the code as follows. This, too, has exactly that problem:

                              test.h

                              #ifndef TEST_H
                              #define TEST_H
                              #include <QDialog>
                              
                              class QLineEdit;
                              class QPushButton;
                              
                              class test : public QDialog
                              {
                                  Q_OBJECT
                              public:
                                  test(QWidget* parent = 0);
                              
                              private slots:
                                  void expression();
                              
                              private:
                                  QLineEdit* result_box;
                                  QPushButton* equal;
                                  QPushButton* quit;
                              };
                              
                              #endif // TEST_H
                              

                              test.cpp

                              #include <QtWidgets>
                              #include "test.h"
                              
                              test::test(QWidget* parent) : QDialog(parent)
                              {
                                result_box = new QLineEdit;
                                equal = new QPushButton(tr("="));
                                quit = new QPushButton(tr("Close"));
                              
                              
                                connect(quit, SIGNAL(clicked(bool)), this, SLOT(close()));
                                connect(equal,SIGNAL(clicked(bool)), this, SLOT(expression()));
                              
                                QHBoxLayout* layout = new QHBoxLayout;
                                layout -> addWidget(result_box);
                                layout -> addWidget(equal);
                                layout -> addWidget(quit);
                              
                                setLayout(layout);
                              }
                              
                              //******************
                              
                              void test::expression()
                              {
                                  QString ss;
                                  double d = 1000000;
                                  QTextStream (&ss) << d;
                                  result_box -> setText(ss);
                              }
                              

                              And main.cpp

                              #include <QApplication>
                              #include "test.h"
                              
                              int main(int argc, char* argv[])
                              {
                                  QApplication app(argc, argv);
                                  test t;
                                  t.show();
                              
                                 return app.exec();
                              }
                              

                              Just run it and click on the = button.

                              tomyT Offline
                              tomyT Offline
                              tomy
                              wrote on last edited by tomy
                              #28

                              I think I should write a code for it like this:

                              if( d is like an int number)
                                  result_box -> setText(QString::number(d , 'f', 0));
                              else if ( d is a double number with n numbers after point)
                                 result_box -> setText(QString::number(d , 'f', n));
                              
                              K 1 Reply Last reply
                              0
                              • tomyT tomy

                                I think I should write a code for it like this:

                                if( d is like an int number)
                                    result_box -> setText(QString::number(d , 'f', 0));
                                else if ( d is a double number with n numbers after point)
                                   result_box -> setText(QString::number(d , 'f', n));
                                
                                K Offline
                                K Offline
                                koahnig
                                wrote on last edited by koahnig
                                #29

                                @tomy
                                Maybe you should have a look to the docs as well. E.g. here

                                In case of integer assignment that would be:

                                int i = 10;
                                result_box -> setText ( QString::number( i ) );
                                

                                Vote the answer(s) that helped you to solve your issue(s)

                                1 Reply Last reply
                                0
                                • tomyT tomy

                                  @kshegunov

                                  expression() returns an int or double value.

                                  I'm pretty sure that functions returns a string, not an int, nor a double.

                                  Don't be that sure. :)
                                  I have this method in my code:

                                  double My_First_Calculator::expression()
                                  

                                  But I think this error is of that ss is a QString.

                                  kshegunovK Offline
                                  kshegunovK Offline
                                  kshegunov
                                  Moderators
                                  wrote on last edited by kshegunov
                                  #30

                                  @tomy said in Showing numbers in decimal not scientific notation:

                                  Don't be that sure. :)

                                  Yes! There's a typo in the code ... :)

                                  ss = qFuzzyCompare(expression(),
                                                   static_cast<qint64>(expression()) ? //< Missing a )
                                                   QString::number(static_cast<qint64>(expression())) :
                                                   QString::number(expression(), 'f')); //< Extra )
                                  

                                  What you want is to have the if with qFuzzyCompare, not with the static cast. It should rather read like this:

                                  ss = qFuzzyCompare(expression(), static_cast<qint64>(expression())) ?
                                                   QString::number(static_cast<qint64>(expression())) :
                                                   QString::number(expression(), 'f');
                                  

                                  If you wish you can of course use the usual if-else construct, not the ternary operator, so the last snippet'd be equivalent to:

                                  if (qFuzzyCompare(expression(), static_cast<qint64>(expression()))
                                      ss = QString::number(static_cast<qint64>(expression()));
                                  else
                                      ss = QString::number(expression(), 'f');
                                  

                                  Read and abide by the Qt Code of Conduct

                                  tomyT 2 Replies Last reply
                                  0
                                  • kshegunovK kshegunov

                                    @tomy said in Showing numbers in decimal not scientific notation:

                                    Don't be that sure. :)

                                    Yes! There's a typo in the code ... :)

                                    ss = qFuzzyCompare(expression(),
                                                     static_cast<qint64>(expression()) ? //< Missing a )
                                                     QString::number(static_cast<qint64>(expression())) :
                                                     QString::number(expression(), 'f')); //< Extra )
                                    

                                    What you want is to have the if with qFuzzyCompare, not with the static cast. It should rather read like this:

                                    ss = qFuzzyCompare(expression(), static_cast<qint64>(expression())) ?
                                                     QString::number(static_cast<qint64>(expression())) :
                                                     QString::number(expression(), 'f');
                                    

                                    If you wish you can of course use the usual if-else construct, not the ternary operator, so the last snippet'd be equivalent to:

                                    if (qFuzzyCompare(expression(), static_cast<qint64>(expression()))
                                        ss = QString::number(static_cast<qint64>(expression()));
                                    else
                                        ss = QString::number(expression(), 'f');
                                    
                                    tomyT Offline
                                    tomyT Offline
                                    tomy
                                    wrote on last edited by
                                    #31
                                    This post is deleted!
                                    1 Reply Last reply
                                    0
                                    • kshegunovK kshegunov

                                      @tomy said in Showing numbers in decimal not scientific notation:

                                      Don't be that sure. :)

                                      Yes! There's a typo in the code ... :)

                                      ss = qFuzzyCompare(expression(),
                                                       static_cast<qint64>(expression()) ? //< Missing a )
                                                       QString::number(static_cast<qint64>(expression())) :
                                                       QString::number(expression(), 'f')); //< Extra )
                                      

                                      What you want is to have the if with qFuzzyCompare, not with the static cast. It should rather read like this:

                                      ss = qFuzzyCompare(expression(), static_cast<qint64>(expression())) ?
                                                       QString::number(static_cast<qint64>(expression())) :
                                                       QString::number(expression(), 'f');
                                      

                                      If you wish you can of course use the usual if-else construct, not the ternary operator, so the last snippet'd be equivalent to:

                                      if (qFuzzyCompare(expression(), static_cast<qint64>(expression()))
                                          ss = QString::number(static_cast<qint64>(expression()));
                                      else
                                          ss = QString::number(expression(), 'f');
                                      
                                      tomyT Offline
                                      tomyT Offline
                                      tomy
                                      wrote on last edited by tomy
                                      #32

                                      @kshegunov

                                      What you want is to have the if with qFuzzyCompare, not with the static cast. It should rather read like this:

                                      ss = qFuzzyCompare(expression(), static_cast<qint64>(expression())) ?
                                                       QString::number(static_cast<qint64>(expression())) :
                                                       QString::number(expression(), 'f');
                                      

                                      If you wish you can of course use the usual if-else construct, not the ternary operator, so the last snippet'd be equivalent to:

                                      if (qFuzzyCompare(expression(), static_cast<qint64>(expression()))
                                          ss = QString::number(static_cast<qint64>(expression()));
                                      else
                                          ss = QString::number(expression(), 'f');
                                      

                                      Sorry, I don't know how I tested it but it doesn't work as it's expected! :(
                                      for example:
                                      2 + 3 = 5 OK
                                      10 ^ 6 = 1000000 OK
                                      2 + 1.5 = 3.500000 !!!

                                      That is, the function QString::number(expression(), 'f'); (with the default precision 6) shows all range of precision whether it's need or not!

                                      Maybe it's what we need:
                                      http://doc.qt.io/qt-5/qtextstream.html#setRealNumberNotation
                                      But how to use it? Docs doesn't offer a little example of it to show how beginners should use it. !!!!!!
                                      (Docs are not for learners/beginners, they are for professionals — if they are professional, so they don't need Docs much => Docs are not useful)

                                      kshegunovK 1 Reply Last reply
                                      0
                                      • tomyT tomy

                                        @kshegunov

                                        What you want is to have the if with qFuzzyCompare, not with the static cast. It should rather read like this:

                                        ss = qFuzzyCompare(expression(), static_cast<qint64>(expression())) ?
                                                         QString::number(static_cast<qint64>(expression())) :
                                                         QString::number(expression(), 'f');
                                        

                                        If you wish you can of course use the usual if-else construct, not the ternary operator, so the last snippet'd be equivalent to:

                                        if (qFuzzyCompare(expression(), static_cast<qint64>(expression()))
                                            ss = QString::number(static_cast<qint64>(expression()));
                                        else
                                            ss = QString::number(expression(), 'f');
                                        

                                        Sorry, I don't know how I tested it but it doesn't work as it's expected! :(
                                        for example:
                                        2 + 3 = 5 OK
                                        10 ^ 6 = 1000000 OK
                                        2 + 1.5 = 3.500000 !!!

                                        That is, the function QString::number(expression(), 'f'); (with the default precision 6) shows all range of precision whether it's need or not!

                                        Maybe it's what we need:
                                        http://doc.qt.io/qt-5/qtextstream.html#setRealNumberNotation
                                        But how to use it? Docs doesn't offer a little example of it to show how beginners should use it. !!!!!!
                                        (Docs are not for learners/beginners, they are for professionals — if they are professional, so they don't need Docs much => Docs are not useful)

                                        kshegunovK Offline
                                        kshegunovK Offline
                                        kshegunov
                                        Moderators
                                        wrote on last edited by kshegunov
                                        #33

                                        What you want to do in the floating point case is not at all trivial. Here you can read on that topic if you are willing to digest the math.

                                        The simpler but inefficient approach is to save the floating point text representation and just discard all the trailing 0 characters manually.

                                        EDIT:
                                        Here's (probably) the most concise way, but requires knowledge of regular expressions, which is yet again for you to read on to understand how or why it works:

                                        if (qFuzzyCompare(expression(), static_cast<qint64>(expression()))
                                            ss = QString::number(static_cast<qint64>(expression()));
                                        else  {
                                            ss = QString::number(expression(), 'f', 17);
                                            ss.replace(QRegularExpression("\\.?0+$"), "");
                                        }
                                        

                                        (Docs are not for learners/beginners, they are for professionals — if they are professional, so they don't need Docs much => Docs are not useful)

                                        You got that backwards. The point of the Qt docs is they are a documentation for Qt itself, they will give no instruction into C++, its types, the types' memory layout and other such technical topics. If you are in need of that, then you need to look elsewhere, for example http://en.cppreference.com/w/

                                        Read and abide by the Qt Code of Conduct

                                        tomyT 1 Reply Last reply
                                        1
                                        • kshegunovK kshegunov

                                          What you want to do in the floating point case is not at all trivial. Here you can read on that topic if you are willing to digest the math.

                                          The simpler but inefficient approach is to save the floating point text representation and just discard all the trailing 0 characters manually.

                                          EDIT:
                                          Here's (probably) the most concise way, but requires knowledge of regular expressions, which is yet again for you to read on to understand how or why it works:

                                          if (qFuzzyCompare(expression(), static_cast<qint64>(expression()))
                                              ss = QString::number(static_cast<qint64>(expression()));
                                          else  {
                                              ss = QString::number(expression(), 'f', 17);
                                              ss.replace(QRegularExpression("\\.?0+$"), "");
                                          }
                                          

                                          (Docs are not for learners/beginners, they are for professionals — if they are professional, so they don't need Docs much => Docs are not useful)

                                          You got that backwards. The point of the Qt docs is they are a documentation for Qt itself, they will give no instruction into C++, its types, the types' memory layout and other such technical topics. If you are in need of that, then you need to look elsewhere, for example http://en.cppreference.com/w/

                                          tomyT Offline
                                          tomyT Offline
                                          tomy
                                          wrote on last edited by
                                          #34

                                          @kshegunov

                                          The point of the Qt docs is they are a documentation for Qt itself, they will give no instruction into C++, its types, the types' memory layout and other such technical topics.

                                          Thanks but I didn't talk about C++, but Docs.
                                          I thought we can look at the Docs as a set of instructions useful for learners to be used to Qt, because they have been frequently suggested to new comers of Qt for reading.
                                          Thanks also for your code.

                                          jsulmJ kshegunovK 2 Replies Last reply
                                          -1

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