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    Class MathContext

    Immutable objects which encapsulate the context settings which describe certain rules for numerical operators, such as those implemented by the BigDecimal class.

    The base-independent settings are:

    • precision: the number of digits to be used for an operation; results are rounded to this precision
    • roundingMode: a RoundingMode object which specifies the algorithm to be used for rounding.

    Sample Usage:

    const { Big, MC, RoundingMode } = require('bigdecimal.js');

    const x = Big('1');
    const y = Big('3');

    const res1 = x.divideWithMathContext(y, new MC(3));
    console.log(res1.toString()); // 0.333

    // You can also use without `new` operator
    const res2 = x.divideWithMathContext(y, MC(3, RoundingMode.UP));
    console.log(res2.toString()); // 0.334

    try {
        x.divide(y);
        // throws since full precision is requested but it is not possible
    } catch (e) {
        console.log(e); // RangeError: Non-terminating decimal expansion; no exact representable decimal result.
    }
    Index
    constructor
    precision roundingMode DECIMAL128 DECIMAL32 DECIMAL64 UNLIMITED
    precision: number

    The number of digits to be used for an operation. A value of 0 indicates that unlimited precision (as many digits as are required) will be used. Note that leading zeros (in the coefficient of a number) are never significant.

    precision will always be non-negative.

    roundingMode: RoundingMode

    The rounding algorithm to be used for an operation. By default it is HALF_UP.

    see RoundingMode

    DECIMAL128: MathContext = ...

    A MathContext object with a precision setting matching the precision of the IEEE 754-2019 decimal128 format, 34 digits, and a rounding mode of HALF_EVEN. Note the exponent range of decimal64 is not used for rounding.

    DECIMAL32: MathContext = ...

    A MathContext object with a precision setting matching the precision of the IEEE 754-2019 decimal32 format, 7 digits, and a rounding mode of HALF_EVEN. Note the exponent range of decimal32 is not used for rounding.

    DECIMAL64: MathContext = ...

    A MathContext object with a precision setting matching the precision of the IEEE 754-2019 decimal64 format, 16 digits, and a rounding mode of HALF_EVEN. Note the exponent range of decimal64 is not used for rounding.

    UNLIMITED: MathContext = ...

    A MathContext object whose settings have the values required for unlimited precision arithmetic. The values of the settings are: precision=0 roundingMode=HALF_UP

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