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Thread: tableview with doubles

  1. #1
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    Default Re: tableview with doubles

    Hello,

    I want a tableView with doubles, for instance:

    QVector<double> data(10);
    for (int i=0;i<10;++i)
    data[i]=1+i/10;
    QStandardItemModel *model = new QStandardItemModel(10,2,this);
    model->setHorizontalHeaderItem(0, new QStandardItem(QString("Column 1")));
    ...
    for(int row=0;row<10;++row)
    for(int col=0;col<2;++col)
    {
    QModelIndex index = model -> index(row,col,QModelIndex());
    model->setData(index,data[row]);
    }
    But I get integers in the table, how can I get doubles: 1.1

    Regards,
    Arend


    Added after 12 minutes:


    I have solved this one
    model->setData(index(row,column),QString::number(yourNum ber, 'f', 3));
    Last edited by Arend; 25th November 2012 at 21:56.

  2. #2
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    Default Re: tableview with doubles

    I have solved this one
    model->setData(index(row,column),QString::number(yourNum ber, 'f', 3));
    No, actually that puts strings (wrapped in QVariant) into the model. For a lot of purposes this may be adequate. If you want an actual QVariant<double> to preserve precision then you need to use the setData() function with a double. You can use a delegate to drive the display form of the double. Compare these:
    Qt Code:
    1. double yourNumber = 10.7002;
    2.  
    3. item.setData(QString::number(yourNumber, 'f', 3), Qt::DisplayRole);
    4. qDebug() << item.data(Qt::DisplayRole) << item.data(Qt::DisplayRole).toDouble();
    5. qDebug() << item.data(Qt::DisplayRole);
    6. // QVariant(QString, "10.700") 10.7
    7.  
    8. item.setData(yourNumber, Qt::DisplayRole);
    9. qDebug() << item.data(Qt::DisplayRole) << item.data(Qt::DisplayRole).toDouble();
    10. // QVariant(double, 10.7002) 10.7002
    To copy to clipboard, switch view to plain text mode 

  3. #3
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    Default Re: tableview with doubles

    Quote Originally Posted by Arend View Post
    Qt Code:
    1. QVector<double> data(10);
    2. for (int i=0;i<10;++i)
    3. data[i]=1+i/10;
    To copy to clipboard, switch view to plain text mode 
    Hmm... let me see.... data[0] = 1, data[1] = 1, data[2] = 1, data[3] = 1, data[4] = 1 ... data[9] = 1

    They are all integers.
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