double-double/node/double-with-err/div-with-err.js

Pure double-double precision functions *with strict error bounds*.

/** @internal */
const u = Number.EPSILON / 2;
/**
 * Returns the result of dividing two double floating point numbers
 * together with an absolute error bound where nE and dE are absolute error
 * bounds on the input values.
 * @param n numerator
 * @param d denominator
 * @param nE absolute value error bound in numerator
 * @param dE absolute value error bound in denominator
 */
function divWithErr(n, d, nE, dE) {
    // estimate the result of the division
    const est = n / d;
    const _n = Math.abs(n);
    const _d = Math.abs(d);
    // if the error in the denominator is too high the error can be 
    // arbitrarily high
    const minD = _d - dE;
    // maxErr is only valid if minD > 0
    if (minD <= 0) {
        // the error can be arbitrarily high; est is mostly irrelevant
        return { est, err: Number.POSITIVE_INFINITY };
    }
    const err = ((_d * nE + _n * dE) / minD ** 2) + u * Math.abs(_n / _d);
    return { est, err };
}
export { divWithErr };
//# sourceMappingURL=div-with-err.js.map