javascript

Decimal Conversions
Chapter 22: The Evolution of JavaScript
Decimal values can be converted into primitive values using one of the following methods:
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doubleValue() — Returns the decimal as a floating - point value .
intValue() — Returns the decimal as an integer .
intValueExtract() — Returns the decimal as an integer. If the result isn ’ t a whole number,
then this method throws a RangeError .
toEngineeringString() — Returns the decimal as string, using exponential notation when
necessary .
toPlainString() — Returns the decimal as a string without using exponential notation .
toString() — Returns the decimal as a string .
At least one of these methods must be used to convert the decimal value to a primitive, because the
regular conversion methods such as parseInt() and parseFloat() will not work with decimal values.
Decimal Math
None of the standard methods on the Math object can be used with decimals, so each Decimal value has
the following methods that perform several of these operations:
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abs() — Converts the decimal value into its absolute value and returns the result as a new
decimal value. This is used instead of Math.abs() .
min(value) — Returns the lesser of the decimal value and value . This is used instead of
Math.min() .
max(value) — Returns the greater of the decimal value and value . This is used instead of
Math.max() .
pow(n) — Raises the current decimal value to the power specified and returns the result as a
new decimal value. This is used instead of Math.pow() .
There aren ’ t as many options for complex mathematical operations involving decimal values, so they
may be of limited usefulness when working with sines, cosines, and other complex computations.
Other Decimal Methods
There are several other methods available on each instance of Decimal that are unique to decimal
values. They are as follows:
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movePointLeft(n) — Returns a new decimal value whose decimal point has been moved
n places to the left.
movePointRight(n) — Returns a new decimal value whose decimal point has been moved
n places to the right.
precision() — Returns the precision of the decimal value as an integer.
scale() — Returns the scale of the decimal value as a new decimal value. The scale is the
number of digits to the right of the decimal point.
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