cacert-testmgr/external/ZendFramework-1.9.5/externals/dojo/dojox/math/round.js

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dojo.provide("dojox.math.round");
dojo.experimental("dojox.math.round");
dojox.math.round = function(/*Number*/value, /*Number?*/places, /*Number?*/increment){
// summary:
// Similar to dojo.number.round, but compensates for binary floating point artifacts
// description:
// Rounds to the nearest value with the given number of decimal places, away from zero if equal,
// similar to Number.toFixed(). Rounding can be done by fractional increments also.
// Makes minor adjustments to accommodate for precision errors due to binary floating point representation
// of Javascript Numbers. See http://speleotrove.com/decimal/decifaq.html for more information.
// Because of this adjustment, the rounding may not be mathematically correct for full precision
// floating point values. The calculations assume 14 significant figures, so the accuracy will
// be limited to a certain number of decimal places preserved will vary with the magnitude of
// the input. This is not a substitute for decimal arithmetic.
// value:
// The number to round
// places:
// The number of decimal places where rounding takes place. Defaults to 0 for whole rounding.
// Must be non-negative.
// increment:
// Rounds next place to nearest value of increment/10. 10 by default.
// example:
// >>> 4.8-(1.1+2.2)
// 1.4999999999999996
// >>> Math.round(4.8-(1.1+2.2))
// 1
// >>> dojox.math.round(4.8-(1.1+2.2))
// 2
// >>> ((4.8-(1.1+2.2))/100)
// 0.014999999999999996
// >>> ((4.8-(1.1+2.2))/100).toFixed(2)
// "0.01"
// >>> dojox.math.round((4.8-(1.1+2.2))/100,2)
// 0.02
// >>> dojox.math.round(10.71, 0, 2.5)
// 10.75
// >>> dojo.number.round(162.295, 2)
// 162.29
// >>> dojox.math.round(162.295, 2)
// 162.3
var wholeFigs = Math.log(Math.abs(value))/Math.log(10);
var factor = 10 / (increment || 10);
var delta = Math.pow(10, -15 + wholeFigs);
return (factor * (+value + (value > 0 ? delta : -delta))).toFixed(places) / factor; // Number
}
if((0.9).toFixed() == 0){
// (isIE) toFixed() bug workaround: Rounding fails on IE when most significant digit
// is just after the rounding place and is >=5
(function(){
var round = dojox.math.round;
dojox.math.round = function(v, p, m){
var d = Math.pow(10, -p || 0), a = Math.abs(v);
if(!v || a >= d || a * Math.pow(10, p + 1) < 5){
d = 0;
}
return round(v, p, m) + (v > 0 ? d : -d);
}
})();
}