var cosh_data = [
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    [1875817529344, 28.953212876533797]
];

var sloppy_tolerance = 1000;  // FIXME

for (var [x, y] of cosh_data)
    assertNear(Math.acosh(x), y, sloppy_tolerance);

assertNear(Math.acosh(1e300), 691.4686750787737, sloppy_tolerance);
assertNear(Math.acosh(1.0000000001), 0.000014142136208675862, sloppy_tolerance);

for (var i = 0; i <= 100; i++) {
    var x = (i - 50) / 5;
    var y = Math.cosh(x);
    var z = Math.acosh(y);
    assertNear(z, Math.abs(x), sloppy_tolerance);
}

for (var i = 1; i < 20; i++)
    assertNear(Math.acosh(Math.cosh(i)), i, sloppy_tolerance);

reportCompare(0, 0, "ok");