dojox.string.sprintf.Formatter.formatDouble
dojo.require("dojox.string.sprintf");
defined in dojox/string/sprintf.js
Usage
function (token) (view source)
var f = parseFloat(token.arg); if(!isFinite(f)){ // isNaN(f) || f == Number.POSITIVE_INFINITY || f == Number.NEGATIVE_INFINITY) // allow this only if arg is number if(typeof token.arg != "number"){ throw new Error("format argument '" + token.arg + "' not a float; parseFloat returned " + f); } // C99 says that for 'f': // infinity -> '[-]inf' or '[-]infinity' ('[-]INF' or '[-]INFINITY' for 'F') // NaN -> a string starting with 'nan' ('NAN' for 'F') // this is not commonly implemented though. //return '' + f; f = 0; } switch(token.doubleNotation) { case 'e': { token.arg = f.toExponential(token.precision); break; } case 'f': { token.arg = f.toFixed(token.precision); break; } case 'g': { // C says use 'e' notation if exponent is < -4 or is >= prec // ECMAScript for toPrecision says use exponential notation if exponent is >= prec, // though step 17 of toPrecision indicates a test for < -6 to force exponential. if(Math.abs(f) < 0.0001){ //print("forcing exponential notation for f=" + f); token.arg = f.toExponential(token.precision > 0 ? token.precision - 1 : token.precision); }else{ token.arg = f.toPrecision(token.precision); } // In C, unlike 'f', 'gG' removes trailing 0s from fractional part, unless alternative format flag ("#"). // But ECMAScript formats toPrecision as 0.00100000. So remove trailing 0s. if(!token.alternative){ //print("replacing trailing 0 in '" + s + "'"); token.arg = token.arg.replace(/(\..*[^0])0*/|>, "$1"); // if fractional part is entirely 0, remove it and decimal point token.arg = token.arg.replace(/\.0*e/|>, 'e').replace(/\.0$/|>,''); } break; } default: throw new Error("unexpected double notation '" + token.doubleNotation + "'"); } // C says that exponent must have at least two digits. // But ECMAScript does not; toExponential results in things like "1.000000e-8" and "1.000000e+8". // Note that s.replace(/e([\+\-])(\d)/, "e$10$2") won't work because of the "$10" instead of "$1". // And replace(re, func) isn't supported on IE50 or Safari1. token.arg = token.arg.replace(/e\+(\d)$/|>, "e+0$1").replace(/e\-(\d)$/|>, "e-0$1"); // Ensure a '0' before the period. // Opera implements (0.001).toString() as '0.001', but (0.001).toFixed(1) is '.001' if(dojo.isOpera){ token.arg = token.arg.replace(/^\./, '0.'); } // if alt, ensure a decimal point if(token.alternative){ token.arg = token.arg.replace(/^(\d+)$/|>,"$1."); token.arg = token.arg.replace(/^(\d+)e/|>,"$1.e"); } if(f >= 0 && token.sign){ token.arg = token.sign + token.arg; } token.arg = token.toUpper ? token.arg.toUpperCase() : token.arg.toLowerCase();
parameter | type | description |
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token |