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node_modules/core-js-pure/modules/esnext.math.sum-precise.js

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+'use strict';
+// based on Shewchuk's algorithm for exactly floating point addition
+// adapted from https://github.com/tc39/proposal-math-sum/blob/3513d58323a1ae25560e8700aa5294500c6c9287/polyfill/polyfill.mjs
+var $ = require('../internals/export');
+var uncurryThis = require('../internals/function-uncurry-this');
+var iterate = require('../internals/iterate');
+
+var $RangeError = RangeError;
+var $TypeError = TypeError;
+var $Infinity = Infinity;
+var $NaN = NaN;
+var abs = Math.abs;
+var pow = Math.pow;
+var push = uncurryThis([].push);
+
+var POW_2_1023 = pow(2, 1023);
+var MAX_SAFE_INTEGER = pow(2, 53) - 1; // 2 ** 53 - 1 === 9007199254740992
+var MAX_DOUBLE = Number.MAX_VALUE; // 2 ** 1024 - 2 ** (1023 - 52) === 1.79769313486231570815e+308
+var MAX_ULP = pow(2, 971); // 2 ** (1023 - 52) === 1.99584030953471981166e+292
+
+var NOT_A_NUMBER = {};
+var MINUS_INFINITY = {};
+var PLUS_INFINITY = {};
+var MINUS_ZERO = {};
+var FINITE = {};
+
+// prerequisite: abs(x) >= abs(y)
+var twosum = function (x, y) {
+  var hi = x + y;
+  var lo = y - (hi - x);
+  return { hi: hi, lo: lo };
+};
+
+// `Math.sumPrecise` method
+// https://github.com/tc39/proposal-math-sum
+$({ target: 'Math', stat: true }, {
+  // eslint-disable-next-line max-statements -- ok
+  sumPrecise: function sumPrecise(items) {
+    var numbers = [];
+    var count = 0;
+    var state = MINUS_ZERO;
+
+    iterate(items, function (n) {
+      if (++count >= MAX_SAFE_INTEGER) throw new $RangeError('Maximum allowed index exceeded');
+      if (typeof n != 'number') throw new $TypeError('Value is not a number');
+      if (state !== NOT_A_NUMBER) {
+        // eslint-disable-next-line no-self-compare -- NaN check
+        if (n !== n) state = NOT_A_NUMBER;
+        else if (n === $Infinity) state = state === MINUS_INFINITY ? NOT_A_NUMBER : PLUS_INFINITY;
+        else if (n === -$Infinity) state = state === PLUS_INFINITY ? NOT_A_NUMBER : MINUS_INFINITY;
+        else if ((n !== 0 || (1 / n) === $Infinity) && (state === MINUS_ZERO || state === FINITE)) {
+          state = FINITE;
+          push(numbers, n);
+        }
+      }
+    });
+
+    switch (state) {
+      case NOT_A_NUMBER: return $NaN;
+      case MINUS_INFINITY: return -$Infinity;
+      case PLUS_INFINITY: return $Infinity;
+      case MINUS_ZERO: return -0;
+    }
+
+    var partials = [];
+    var overflow = 0; // conceptually 2 ** 1024 times this value; the final partial is biased by this amount
+    var x, y, sum, hi, lo, tmp;
+
+    for (var i = 0; i < numbers.length; i++) {
+      x = numbers[i];
+      var actuallyUsedPartials = 0;
+      for (var j = 0; j < partials.length; j++) {
+        y = partials[j];
+        if (abs(x) < abs(y)) {
+          tmp = x;
+          x = y;
+          y = tmp;
+        }
+        sum = twosum(x, y);
+        hi = sum.hi;
+        lo = sum.lo;
+        if (abs(hi) === $Infinity) {
+          var sign = hi === $Infinity ? 1 : -1;
+          overflow += sign;
+
+          x = (x - (sign * POW_2_1023)) - (sign * POW_2_1023);
+          if (abs(x) < abs(y)) {
+            tmp = x;
+            x = y;
+            y = tmp;
+          }
+          sum = twosum(x, y);
+          hi = sum.hi;
+          lo = sum.lo;
+        }
+        if (lo !== 0) partials[actuallyUsedPartials++] = lo;
+        x = hi;
+      }
+      partials.length = actuallyUsedPartials;
+      if (x !== 0) push(partials, x);
+    }
+
+    // compute the exact sum of partials, stopping once we lose precision
+    var n = partials.length - 1;
+    hi = 0;
+    lo = 0;
+
+    if (overflow !== 0) {
+      var next = n >= 0 ? partials[n] : 0;
+      n--;
+      if (abs(overflow) > 1 || (overflow > 0 && next > 0) || (overflow < 0 && next < 0)) {
+        return overflow > 0 ? $Infinity : -$Infinity;
+      }
+      // here we actually have to do the arithmetic
+      // drop a factor of 2 so we can do it without overflow
+      // assert(abs(overflow) === 1)
+      sum = twosum(overflow * POW_2_1023, next / 2);
+      hi = sum.hi;
+      lo = sum.lo;
+      lo *= 2;
+      if (abs(2 * hi) === $Infinity) {
+        // rounding to the maximum value
+        if (hi > 0) {
+          return (hi === POW_2_1023 && lo === -(MAX_ULP / 2) && n >= 0 && partials[n] < 0) ? MAX_DOUBLE : $Infinity;
+        } return (hi === -POW_2_1023 && lo === (MAX_ULP / 2) && n >= 0 && partials[n] > 0) ? -MAX_DOUBLE : -$Infinity;
+      }
+
+      if (lo !== 0) {
+        partials[++n] = lo;
+        lo = 0;
+      }
+
+      hi *= 2;
+    }
+
+    while (n >= 0) {
+      sum = twosum(hi, partials[n--]);
+      hi = sum.hi;
+      lo = sum.lo;
+      if (lo !== 0) break;
+    }
+
+    if (n >= 0 && ((lo < 0 && partials[n] < 0) || (lo > 0 && partials[n] > 0))) {
+      y = lo * 2;
+      x = hi + y;
+      if (y === x - hi) hi = x;
+    }
+
+    return hi;
+  }
+});