Function fromTwos

lib.esm/utils/maths.js:19–31

(_value, _width)

 *  If the highest bit is ``1``, the result will be negative.
 */
export function fromTwos(_value, _width) {
    const value = getUint(_value, "value");
    const width = BigInt(getNumber(_width, "width"));
    assert((value >> width) === BN_0, "overflow", "NUMERIC_FAULT", {
        operation: "fromTwos", fault: "overflow", value: _value
    });
    // Top bit set; treat as a negative value
    if (value >> (width - BN_1)) {
        const mask = (BN_1 << width) - BN_1;
        return -(((~value) & mask) + BN_1);
    }
    return value;
}
/**
 *  Convert %%value%% to a twos-compliment representation of
 *  %%width%% bits.