This question already has answers here:
How to convert a double to an int in Dart?
(11 answers)
How do you round a double in Dart to a given degree of precision AFTER the decimal point?
(28 answers)
Closed 3 years ago.
I want to round a double.
Double x = 5.56753;
x.toStringAsFixed(2);
When i put this, it gives 5.57000.
But i want to get 5.57. How do i get it?
there is num class contained function round():
Num
double numberToRound = 5.56753;
print(numberToRound.round());
//prints 6
If you want decimals
double n = num.parse(numberToRound.toStringAsFixed(2));
print(n);
//prints 5.57
check comment sujestion
For rounding doubles checkout: https://api.dartlang.org/stable/2.4.0/dart-core/double/round.html
Rounding won't work in your case because docs says:
Returns the integer closest to this.
So it will give 6 instead 5.57.
Your solution:
double x = 5.56753;
String roundedX = x.toStringAsFixed(2);
print(roundedX);
Related
This question already has answers here:
How to know if a number is odd or even in Swift?
(5 answers)
Closed 11 months ago.
im absolutely new to development, and trying to learn swift.
Right now i know how to make random number, and my next step is:
Im trying to understand how to check if my random number (127) could be divided by 2 without decimals ?
I have no idea how to do it.
There is a specific API isMultiple(of:) in Standard Library for this purpose
let random = Int.random(in: 0..<100)
let isEven = random.isMultiple(of: 2)
You can use operator % - remainder operator
example:
if randomNumber % 2 == 0 {
print("\(randomNumber) is even")
} else {
print("\(randomNumber) is odd")
}
This question already has answers here:
Is floating point math broken?
(31 answers)
Closed 2 years ago.
Can someone explain to me why the following sum gives wrong result in dart?
final double result = 90071992547409.9 + 0.01;
print(result);
It prints the number 90071992547409.92
According to Dart documentation:
Dart doubles are 64-bit floating-point numbers as specified in the IEEE 754 standard.
It's because of floating-point arithmetic. In your case (I used this converter):
90071992547409.9 = 90071992547409.90625 ~= 90071992547409.91
0.01 = 0.01000000000000000020816681711721685132943093776702880859375 ~= 0.01
90071992547409.91 + 0.01 = 90071992547409.92
The best solution in dart is to use the decimal package.
This question already has answers here:
How to properly format currency on ios
(8 answers)
How to input currency format on a text field (from right to left) using Swift?
(9 answers)
Closed 4 years ago.
I have a values like that: 100, 1220, 10015 basically last 2 digits are cents and I need to convert to dollar (currency) format similar to:
1.00, 12.20, 100.15
Can somebody suggest a quick implementation?
var a = 1011
var b = Double(a) / 100
This question already has answers here:
A way to round Floats down
(11 answers)
Closed 6 years ago.
I have number num = 24.89808 and want to round it to 24.89
How can i do it?
i tried num.round(2) but it gives me 24.9 also number_to_currency=>24.90
If you are talking about rounding, 24.9 is by all means the correct result. Whether you are interested in ceiling it, here you go:
(24.89808 * 100).floor / 100.0
#⇒ "24.89"
First convert that into a decimal and then round it two two places,
Try this command,
num.to_d.round(2, :truncate).to_f
2.2.4 :040 > num = 24.89808
=> 24.89808
2.2.4 :041 > num.to_d.round(2,:truncate).to_f
=> 24.89
This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
How can I round a float value to 2 post decimal positions?
Lets say I have a double number of 3.46.
How do I round it to 3.50?
I tried
NSLog(#"res: %.f", round(3.46));
but it return 3.
Do some calculations....
float f=3.46;
float num=f+0.05;//3.51
int intNum=num*10;//35
float floatNum=intNum/10.0;//3.5
NSLog(#"res: %.2f", floatNum); //3.50
Following code may help
i = roundf(10 * i) / 10.0;
where i is your float variable
If you're willing to live with the rounding rules from printf, then the following should suffice when rounding for presentation:
NSLog(#"res: %.1f0", 3.46);
Note that the 0 is just a normal character that is added after the value is formatted to the appropriate number (1) of decimal places. This approach should be usable with [NSString stringWithFormat:] as well.
The original code results in "3" because round always returns an integral value.
YMMV; I don't even use iOS.