rounding

问题 I have a QLabel that i fill in red with the stylesheet, but the QLabel is rectangular, and I want a circle. I try to add border-radius, but it doesn't work, maybe because i put my QLabel in a formLayout. Is there a simple method to have a round QLabel by using stylesheet ? Thanks. EDIT : Using a picture seems more easier than doing this now. 回答1: Create an image that you use as a mask and set that on the label by calling setMask. As the documentation states: - Causes only the pixels of the

问题 Background: We have an embedded system that converts linear positions (0 mm - 40 mm) from a potentiometer voltage to its digital value using a 10-bit analog to digital converter. ------------------------ 0mm | | 40 mm ------------------------ We show the user the linear position at 1 mm increments. Ex. 1mm, 2mm, 3mm, etc. The problem: Our system can be used in electromagnetically noisy environments which can cause the linear position to "flicker" due to noise entering the ADC. For example, we

问题 I'd like to round floating point numbers to the nearest integer, going towards positive infinity when there is a tie for "nearest integer". use std::num::Float; fn main() { assert_eq!(-0.0, (-0.5).round()); // fails! } However, the docs for round say: Round half-way cases away from 0.0. I haven't seen anything that would allow me to change the rounding mode, but there's got to be some way, right? 回答1: It appears that the implementation of Float::round , at least for f32 and f64 , forward to

问题 While trying to figure out how to round a float like 1.255 to the nearest hundredth, I found something interesting. I'm using gcc 4.4.5 on Debian 6. int x = (1.255 * 100) + 0.5; // gives me back 125 instead of 126. float y = (1.255 * 100) + 0.5; // gives me back 126.000000. Why is is that when I save to an int I get back 125 and not 126 ? In fedora when I save the above expression to an int I get back 126 . Is this a gcc bug in debian ? Any help would be greatly appreciated. Thanks. 回答1:

问题 I'm new to mysql and need some basic things. I need to round the decimals like : 21,4758 should be 21,48 0,2250 should be 0,22 23,0850 should be 23,08 22,9950 should be 22,99 I tried lots of thing but couldn't make it. Thanks. 回答1: DECLARE @old decimal(38, 10) DECLARE @p decimal(38, 10) SET @p = 21.4758 SET @p = @p * 100 SET @p = @p - 0.01 SET @p = ROUND(@p, 0) SET @p = @p / 100.0 SELECT @p 回答2: Try this: // round the value to two decimal places SELECT ROUND(<YOUR_FIELD>, 2) field FROM <YOUR

问题 If I have a decimal , how do I get a string version of it with two decimal places? This isn't working: Math.Round(myDecimal, 2).ToString("{0.00}"); 回答1: Don't use the curly brackets, they are for embedding a formatted value in a longer string using string.Format . Use this: myDecimal.ToString("0.00"); 回答2: Maybe i'm wrong, but i've tried myDecimal.ToString(); and it worked. 回答3: Assuming myDecimal is a System.Decimal , then Math.Round(myDecimal, 2).ToString(); will display two decimal digits

问题 I have an issue regarding conversion from float to c++ string using ostringstream. Here is my line: void doSomething(float t) { ostringstream stream; stream << t; cout << stream.str(); } when t has value -0.89999 it is round off to -0.9, but when it's value is 0.0999 or lesser than this say 1.754e-7, it just prints without round off. what can be the solution for this. 回答1: You need to set the precision for ostringstream using precision e.g stream.precision(3); stream<<fixed; // for fixed

问题 Appears that the default Python round(1 / 2) gives 0. How to round float 0.5 up to 1.0, while still rounding 0.45 to 0.0, as the usual school rounding? NOTE: Sorry for deleting and posting this again, but it was incorrectly marked as duplicate of another question. 回答1: It is actually currently considered proper to NOT blindly round *.5 up. Rather, it is proper to round *.5 to the nearest even number. Python 3 implements this "proper" form of "banker rounding", but a lot of other languages don

问题 I'm having a problem with np.round, np.around where it is not rounding properly. I can't include code, because when I do it manually set the value (as opposed to use the my data), the return works, but here is the output: In [177]: a Out[177]: 0.0099999998 In [178]: np.round(a,2) Out[178]: 0.0099999998 In [179]: np.round(a,1) Out[179]: 0.0 What am I missing? The dtype of a is float32, do I need to change this? 回答1: Try creating np.float32(0.01) and you will see your answer. You are getting

问题 As we all know, floating point arithmetic is not always completely accurate, but how do you deal with its inconsistencies? As an example, in PHP 5.2.9: (this doesn't happen in 5.3) echo round(14.99225, 4); // 14.9923 echo round(15.99225, 4); // 15.9923 echo round(16.99225, 4); // 16.9922 ?? echo round(17.99225, 4); // 17.9922 ?? echo round(25.99225, 4); // 25.9922 ?? echo round(26.99225, 4); // 26.9923 How would you work around this? 回答1: Welcome to IEEE754, enjoy your stay. Use bc or gmp