How to display a double?

[TomASS]

Hello, I would like to display a double number into a MessageBox:

if I write:

double d = 0.75;
QString str = QString("delta: %1").arg(d, 0, 'g', 6);
QMessageBox::information(0,"Time","Value: "+str+".\n");

double d = 0.75;
QString str = QString("delta: %1").arg(d, 0, 'g', 6);
QMessageBox::information(0,"Time","Value: "+str+".\n");

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i's display ok: Value: 0.75.

But if I write:

double d = 3/4;
QString str = QString("delta: %1").arg(d, 0, 'g', 6);
QMessageBox::information(0,"Time","Value: "+str+".\n");

double d = 3/4;
QString str = QString("delta: %1").arg(d, 0, 'g', 6);
QMessageBox::information(0,"Time","Value: "+str+".\n");

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i's display wrong: Value: 0.. Why and what I should write to display Value: 0.75?

[vcp]

Hi,

You can use this code:

QString("%L0").arg(v,0,'f',2)

***Note the use of 'f' parameter.***

for example:

double v = 150.63;

QString qsValue = QString("%L0").arg(v,0,'f',2);

qDebug() << qsValue;

[wysota]

But if I write:

double d = 3/4;
QString str = QString("delta: %1").arg(d, 0, 'g', 6);
QMessageBox::information(0,"Time","Value: "+str+".\n");

double d = 3/4;
QString str = QString("delta: %1").arg(d, 0, 'g', 6);
QMessageBox::information(0,"Time","Value: "+str+".\n");

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i's display wrong: Value: 0.. Why and what I should write to display Value: 0.75?

3/4 is 0. If you divide two integers the result is also an integer.

[LeNsTR]

Try it:

double d = 3.0 / 4;

double d = 3.0 / 4;

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