Truncating float numbers while displaying in Label field

[o6a6r9v1p]

i have to display float number with 2 digits after decimal point(truncate).

I have used
Label_Value->setText( QString::number(value, 'f', 2));

it is rounding a larger value while displaying the value.

Then i used parseFloat()

value= parseFloat(value).toFixed(2);
Label_Value->setText( QString::number(value, 'f', 2));

This is giving error message

'parseFloat' was not declared in this scope.

Searched in the net. didnot get any idea.
What is to added/declared to use parseFloat().

Thanks.

[jsulm]

@o6a6r9v1p said in Truncating float numbers while displaying in Label field:

parseFloat

What is parseFloat?

[Toniy]

If you need floating value with certain precision without ceiling, try to get string longer by one symbol (three in your case) and remove all symbols that after second fractional digit:

// Let's consider three cases:
// 1. value == 2.65796541324 (longer than two fractional symbols);
// 2. value == 2.6 (shorter);
// 3. value == 2 (integer).
QString str(QString::number(value, 'f', 3));  // 1. str == "2.658"; 2. str == "2.600"; 3. str == "2.000"
str.chop(str.length() - (str.indexOf('.') + 3)); // 1. str == "2.65"; 2. str == "2.60"; 3. str == "2.00"
Label_Value->setText(str);

[VRonin]

parseFloat is Javascript, not C+++

Label_Value->setText( QString::number(std::trunc(value*100.0)/100.0, 'f', 2)); will do the trick (remember to add #include <cmath>).

[o6a6r9v1p]

@VRonin

I am mistaken about parseFloat, as you pointed out.
modified code as you told, it is working now.

Thank you.

[o6a6r9v1p]

@Toniy
Thank you,