if (document.all) { document.styleSheets[0].addRule(".RightAlign","text-align: right"); document.styleSheets[0].addRule(".CalcTable","background-color: buttonface"); document.styleSheets[0].addRule(".CalcCaptionBack","background-color: activecaption"); document.styleSheets[0].addRule(".CalcCaptionText","color: captiontext"); } ResultsOpen=false;HelpOpen=false; var ResultsArray=new MakeArray(80); ResultIndex=1; wrapped=false; function ValidateCalls() {var CallsValue; with (document.calls_form) {CallsValue=CallsNumber(); if (((CallsValue<1) || (CallsValue>10000)) && ef) {alert("Number of calls must be between 1 and 10000"); Calls_Edit.value=""} }} function ValidateDuration() {var DurationValue; with (document.calls_form) {DurationValue=DurationNumber(); if ((DurationValue<10) || (DurationValue>1800)) {alert("Call duration must be between 10 and 1800 seconds"); Duration_Edit.value=""} }} function ValidateDelay() {var DelayValue; with (document.calls_form) {DelayValue=DelayNumber(); if ((DelayValue<1) || (DelayValue>600)) {alert("Average delay must be between 1 and 600 seconds"); Delay_Edit.value=""} }} function ResultsPressed() {var index,HasWrapped; if ((ResultIndex==1) && (!wrapped)) { alert("There are no results to display yet!"); } else { // Specifying size sometimes causes problems in IE4 // ResultsWindow=window.open('','ResultsW','height=250,width=348,menubar,scrollbars,resizable'); ResultsWindow=window.open("" , "ResultsW" , "toolbar=0 , location=0 , directories=0 , status=0 , menubar=1 , scrollbars=1 , resizable=1 , copyhistory=0"); ResultsWindow.document.writeln(""); ResultsWindow.document.writeln(""); ResultsWindow.document.writeln("Erlang C Calculator Results Table"); ResultsWindow.document.writeln(""); ResultsWindow.document.write("

Erlang C Calculator Results Table

") ResultsWindow.document.write("

Here are the results (max 20) of the Erlang C "); ResultsWindow.document.write("Calculator. The unknown figures are shown in red.

"); ResultsWindow.document.write("

"); ResultsWindow.document.write(""); ResultsWindow.document.write(""); ResultsWindow.document.write(""); HasWrapped=!wrapped; if (wrapped) {index=ResultIndex} else {index=1}; for (;(index!=ResultIndex) || (!HasWrapped);index++) { ResultsWindow.document.write(""); if ((index==20) && (wrapped)) {index=0;HasWrapped=true;}} now=new Date(); ResultsWindow.document.write("
Calls per hourCall duration (s)Avge delay (s)Agents required
"); ResultsWindow.document.write(ResultsArray[index]); ResultsWindow.document.write(""); ResultsWindow.document.write(ResultsArray[index+20]); ResultsWindow.document.write(""); ResultsWindow.document.write(ResultsArray[index+40]); ResultsWindow.document.write(""); ResultsWindow.document.write(ResultsArray[index+60]); ResultsWindow.document.write("

© Westbay Engineers Ltd. 2001.
"); ResultsWindow.document.write("Results displayed - "+now.toLocaleString()+""); ResultsWindow.document.write(""); ResultsWindow.document.close(); ResultsOpen=true; }} ef=(window.location.hostname.indexOf("lang.co")!=-1) || (window.location.hostname.indexOf("bay-en")!=-1); function HelpPressed() {HelpWindow=window.open('help.html','HelpW','height=300,width=348,menubar,scrollbars,resizable'); HelpOpen=true; } function CalcPressed() {var agents,traffic,DurationValue,DelayValue; with (document.calls_form) {if ((Calls_Edit.value=="") || (Duration_Edit.value=="") || (Delay_Edit.value=="")) {alert("All three boxes must be filled in")} else {DurationValue=DurationNumber(); CallsValue=CallsNumber(); DelayValue=DelayNumber(); agents=Math.round((DurationValue*CallsValue/3600)-0.5)+1; traffic=CallsValue*DurationNumber()/3600; while (ECDelayAll(traffic,agents,DurationValue)>DelayValue) {agents++} alert("The number of agents required during this hour is " + agents + ".") ResultsArray[ResultIndex]=CallsValue; ResultsArray[ResultIndex+20]=DurationValue; ResultsArray[ResultIndex+40]=DelayValue; ResultsArray[ResultIndex+60]=agents; ResultIndex++; if (ResultIndex==21) {ResultIndex=1;wrapped=true;} if (ResultsOpen) {ResultsPressed()}; } }} function CallsNumber() {return parseInt(ef*document.calls_form.Calls_Edit.value) } function DurationNumber() {return parseInt(document.calls_form.Duration_Edit.value) } function DelayNumber() {return parseInt(document.calls_form.Delay_Edit.value) } function EB(traffic,plines) {var PBR,index; if (traffic>0) {PBR=(1+traffic)/traffic; for (index=2;index!=plines+1;index++) {PBR=index/traffic*PBR+1; if (PBR>10000) {return 0;}} return 1/PBR;} else {return 0;} } function EC(traffic,plines) {var EBResult,probability; EBResult=EB(traffic,plines); probability=EBResult/(1-(traffic/plines)*(1-EBResult)); if (probability>1) {return 1} else {return probability}; } function ECDelayAll(traffic,plines,HoldTime) {return EC(traffic,plines)*HoldTime/(plines-traffic); } function MakeArray(n) { this.length = n; for (var i = 1; i <= n; i++) { this[i] = 0 } return this }