Dart Numbers

In this chapter, we will learn about dart numbers data types and the properties and methods that are available in dart.

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Dart Numbers

Numbers represent integer values and floating-point values. For example,

int number = 5;

For integer values, keyword int is used. Let’s see an example,

int number1 = 5;
int number2 = 88;

And for floating values, keyword double is used. For example,

double number1 = 5.324;
double number2 = 88.3258;

The num keyword represents numbers in general. Here’s an example,

num number1 =5.324;
num number2 = 5;

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Number Properties

Dart also provides various properties and methods that make the life of a programmer easier.

Some of the Number properties are:

Property	Description
isFinite	True if the number is finite
isInfinite	True if the number is positive infinity or negative infinity
isNaN	True if the number is the double Not-a-Number value
hashcode	Returns a hash code for a numerical value
isNegative	True if the number is negative
isEven	Returns true if the number is even number
isOdd	Returns true if the number is odd number
sign	Returns -1, 0 or +1 depending on the sign and numerical value of the number

Number Properties Example

void main() {
int number1 = 100;
print(number1.isFinite);

print(number1.isInfinite);

print(number1.isNaN);

print(number1.hashCode);

print(number1.isNegative);

int number2 = -100;
print(number2.isNegative);

print(number1.isEven);

print(number1.isOdd);
}

Output

true
false
false
100
false
true
true
false

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Number Methods

Dart number data types also have various useful string methods available. Some of them are:

Methods	Description
toInt()	Returns the integer equivalent of the number
toDouble()	Returns the double equivalent of the number
truncate()	Returns an integer after discarding any decimal digits
round	Returns the integer closest to the current numbers
floor	Returns the greatest integer not greater than the current number
remainder	Returns the truncated remainder after dividing the two numbers
toString	Returns the string equivalent representation of the number
ceil	Returns the least integer no smaller than the number
abs	Returns the absolute value of the number
compareTo	Compare a number to another

Number Methods Examples

void main() {

int number = 5;
double number1 = 5.224;
print(number1.toInt());

print(number1.truncate());

double number3 = 5.224;
double number4 = 5.66;

print(number3.round());
print(number4.round());

print(number3.floor());
print(number4.floor());

print(number.remainder(2));
print(number.toString());

print(number.compareTo(5));
print(number1.compareTo(5.224));

}

Output

5
5
5
6
5
5
1
5
0
0

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That’s it for this chapter. See you one the next one.