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JavaScript Include Files.

See "About This JavaScript Site" in JavaScript Index and Introduction.

As with other pages, the date of the page is independent of the dates of the include files shown.

Overview of Include Files

Where code is common to more than one Web page, it is effective to put it into one or more "include" files, so that only one copy needs to be maintained and transmitted.

With an invocation such as

<script type="text/javascript" src="include2.js"></script>

<script type="text/javascript"> contents </script>

An include file can contain functions, declarations, and other statements; but not overt HTML. Here is a representation of my complete include2.js (used only in JavaScript Tests, and below) as a trivial example (the comments are not necessary) :-

function Caption2() { // JAVASCRIPT INCLUDE FILE - (c) J R Stockton >= 2006-12-24 // http://www.merlyn.demon.co.uk/include2.js } var TestCounter = 1 // end.

Often, the include statements will be placed at or near the top of a Web page, in the HEAD or BODY section.

Extension

Extension .js is commonly used, but has the disadvantage when used in the URL of a link that the file may then be treated as a Windows executable.

File Existence

If a required include file is missing, code needing it will fail, perhaps confusingly. After invoking, I test by code like :-

if (typeof(TestCounter)=='undefined') alert('File include2.js fault, RSVP!')

In fact, I check variables defined at each end of the file, since it is possible for a file to be only partially up/down-loaded.

Type Omission

In a <script ... > part, if the type attribute is not set, the previous value is used; the default is JavaScript. The only other type I actually know much of is VBScript.

Defer

I have read that adding defer="defer" in the script tag allows page parsing to continue, since the included file code does not invoke any writes.

Dynamic Inclusion

Code to select an include file can be written into a page while it is loading, but the contents must not be used until the file has loaded - or so it seems.

function QQ() { document.write( '<script type="text/javascript" src="include2.js"><\/script>') }

More elegantly, see Bart Van der Donck in news:c.l.j 2008-03-25.

My Include Files

Disused JavaScript routines are coded in include0.js.

General JavaScript routines are coded in include1.js, including the routines used to display in boxes with coloured borders.

A test variable is declared in include2.js.

General JavaScript date routines are coded in include3.js, and widely used in my pages.

Other include files are specific to my Rounding, Zeller, and other Easter pages.

The include files may also define a few variables.

My code can be used as code (where the boxes do not suffice, try View Source, in the page or on a browser menu), but should not be re-published.

Display of Code on This Page

Display of code, and parts of this page, require JavaScript.

Microsoft Internet Explorer (4-7, +?) and Google Chrome display functions and methods as written, in the original layout and complete with comment. If your browser does not (e.g. Firefox, Opera, Safari), you should resort to View Source or an independent viewer.

Read "Code Display on This Site" in Index and Introduction, and page Code Boxes. For the coding of the double-bordered boxes, see ShoFFF() etc. under "Code Display" in the include1.js section of this page.

Simple Functions are shown in full. Added Methods may be shown as function anonymous with their names following in comment.

Some supplementary Methods may be conditionally defined; if you already have them, [native code] will be shown.

Functions Caption. contain identifying comment, and are functions merely in order that the comment can be shown.

Limits

Some routines, particularly date ones, have limited range :-

• The Date Object is limited to about ±275000 years
• Integer operators are 32-bit, so range is 0 to 4294967295

Contents of my file include0.js

I no longer use this include file or these functions elsewhere.

Contents of my file include1.js

function Caption1() { // JAVASCRIPT INCLUDE FILE - (c) J R Stockton >= 2010-02-08 // http://www.merlyn.demon.co.uk/include1.js // Routines may be copied, but URL must not be linked to. }

BR

function BR() { document.writeln("<br>") }

Wryt

// Write string S to element which has ID function Wryt(ID, S) { document.getElementById(ID).innerHTML = S }

Leading Zeroes

// Various functions for Number to 2-digit String function LS(n) { return String(n).replace(/\b(\d)\b/g, '0$1') } function lz(n) { var t = n+"" ; return t.length==1 ? "0"+t : t } function LZ(n) { return (n!=null&&n<10&&n>=0?"0":"") + n } // LZ is generally preferred, but LS does multiple insertions

// Number to 3-digit String function LZZ(n) { return (n!=null&&n<100&&n>=0?"0"+LZ(n):""+n) }

String Utilities

// return N spaces function Space(N) { var S = "" ; while (N-->0) S += " " ; return S }

/* TrimS implements Method trim() of String, which removes leading & trailing whitespace */ function TrimS() { // used for String.prototype.trim \u00A0? return (this.toString() ? this.toString().replace(/\s+$|^\s+/g, "") : "") }

// T8 expands TABs to spaces in a multi-line String function T8(Str) { // Expands Tab to spaces up to Column 8N (EjH) var Lines = Str.split("\n"), L, Parts, Row, P, S8 = " " for (L=0 ; L < Lines.length ; L++) { Parts = Lines[L].split("\t") Row = "" ; P = 0 ; while (1) { Row += Parts[P] if (++P==Parts.length) break Row += S8.substring(Row.length%8) /* 1..8 spaces */ } Lines[L] = Row } return Lines.join("\n") }

Dummy

function DummyF(X) { return X /* Dummy */ }

Number Formatting

See in Rounding 1

// With + for positive function Sign(X) { return X>0 ? "+" : X<0 ? "-" : " " } function Sygn(X) { return (X+1/X)<0 ? "-" : "+" /* signed zero */ } function Sgnd(X) { return Sign(X) + Math.abs(X) }

// Extension to Left function SpcsTo(S, L) { S += "" while (S.length<L) S = " " + S ; return S } function ZeroTo(S, L) { S += "" while (S.length<L) S = "0" + S ; return S } function ChrsTo(S, L, C) { // ChrsTo is a new PrfxTo for (var i = String(S).length ; i < L ; i++) S = C + S return S }

// Number rounded to fixed-point String // StrU unsigned, StrS signed, StrT U padded, StrW S padded function StrC(X, M, N, B) { var St, J // to M digits point N digits St = String(Math.round((B ? Math.abs(X) : X)*Math.pow(10, N))) if (X===null || /\D/.test(St)) return ChrsTo(X, M+N+1+B, " ") St = ChrsTo(St, M+N, "0") ; J = St.length - N // 20090113 return (B ? Sign(X) : "" ) + St.substring(0, J) + "." + St.substring(J) } function StrU(X, M, N) { return StrC(X, M, N, 0) /* X>-0.5e-N */ } function StrS(X, M, N) { return StrC(X, M, N, 1) /* uses Sign */ } function StrT(X, M, N) { return ChrsTo(StrU(X, 1, N), M+N+1, " ") } function StrW(X, M, N) { return ChrsTo(StrS(X, 1, N), M+N+2, " ") }

function toFixed() { [native code] }

// This set is used function Expo(E) { return "e" + (E<0?'-':'+') + LZ(Math.abs(E)) } function GetSEM(X) { // returns Sign Mantissa Exponent (base 10) var U, Obj = { S : Sign(X), E : 0, M : X==U?U:Math.abs(X) } with (Obj) { if (M==0 || !isFinite(M)) return Obj while (M >= 10) { E++ ; M /= 10 } while (M < 1.0) { E-- ; M *= 10 } } return Obj } function NumDecSigFig(X, N) { var U // returns a Number if (X==0||X==U) return X with (GetSEM(X)) var P = Math.pow(10, N-E-1) return Math.round(X*P)/P } function StrSigFigFxd(X, N) { var U // ?? for 2 <= N <= 16 ?? if (X==U) return " " + U with (GetSEM(X)) { var P, Q P = Math.pow(10, N-E-1) ; Q = Math.round(Math.abs(X)*P)/P return S + StrU(Q, 1, Math.max(1, N-E-1)) } } function StrSigFigExp(X, N) { // ?? for 2 <= N <= 16 ?? with (GetSEM(X)) return S + StrU(M, 1, N-1) + (isFinite(M) ? Expo(E) : " ") }

function SigFigSet() { // sets globals SigFigNum = NumDecSigFig SigFigFxd = StrSigFigFxd SigFigExp = StrSigFigExp }

function SigFigAre() { var IzN = "\t" document.write( "Across this site,\n", "Name Used\tThe Function\tReturn".italics(), "\nSigFigNum", IzN, NameFunc(SigFigNum), "\tNumber", "\nSigFigFxd", IzN, NameFunc(SigFigFxd), "\tString '#.#'", "\nSigFigExp", IzN, NameFunc(SigFigExp), "\tString '#.#e#'") }

Across this site,
Name Used	The Function	Return
SigFigNum	NumDecSigFig	Number
SigFigFxd	StrSigFigFxd	String '#.#'
SigFigExp	StrSigFigExp	String '#.#e#'

Maths

// CAVEAT : consider behaviour for X<0. function Div(X, Y) { return Math.floor(X/Y) /* full range */ } function Mod(X, Y) { return X - Math.floor(X/Y)*Y }

Function Name

function NameFunc(Fn) { // Fn is a function; return its name var A = Fn.toString().match(/function\s+(\w+)\(/) return A ? A[1] : "anon" }

User Input

function userIn(Ctrl) { // input for numbers and expressions return +eval(Ctrl.value) } function GetNum(Ctrl) { // input for expressions, allows spaces return +eval(Ctrl.value.replace(/[ ]/g, '')) } function RadBtns(Rbtn, Arr) { var Q, J=0 // Read RadioButtons while (Q=Rbtn[J]) { if (Q.checked) return Arr[J] ; J++ } }

Code Display

var BoxW = 69

Current routines, self-shown by ShoFFF(ShoFFF, ... , 0, "-- ... :", ...) :-

function ShoFFF() { // Show code of ArgListed functions, strings; 0 ends visibles with (ShoGen(arguments)) Depikt(BoxW, Cnt, Str, "lightgreen") } function ShoOut(Fn) { // N.B. this calls Fn(), shows output in PRE document.writeln("<pre class=OUT>") Fn() document.writeln("<\/pre>") } function ShoDoo(Fn) { // N.B. this calls Fn() - ADD show others ? ShoCod(Fn) ; Fn() /* no visible output expected */ } function ShoDuu(Fn) { // N.B. this calls Fn() - ADD show others ? ShoCod(Fn) ; ShoOut(Fn) /* visible output expected */ } function ShoBad() { document.body.lastChild.style.backgroundColor = "#ffc0c0" } -- One visible blank line next; scroll for internal code : function ShoCod(Fn) { // N.B. Fn() should be called externally var St = ShoTrim(Fn.toString()) Depikt(BoxW, ShoLinCnt(St, BoxW), St, "red") } function SafeHTML(S) { return S.split("&").join("&amp;").split("<").join("&lt;"). split(">").join("&gt;") } function Depikt(X, Y, S, Hue) { // String S is shown in a box document.writeln( "<p class=DEPIKT align=center>\n<textarea readonly wrap=virtual", " style=\"border: double thick ", Hue || "black", " ;\"", " cols=", X, " rows=", Y, ">\n", SafeHTML(S), "<\/textarea><\/p>") } function ShoTrim(St) { var match = /\S([\s\S]*\S)*/.exec(St) return match ? match[0] : " eh? " } function ShoLinCnt(St, Mx) { // counts lines when wrapped at lineLength Mx var Ch, j = xj = CR = NL = 0, Len = St.length, X = 1 while (j<Len) { Ch = St.charCodeAt(j++) if (Ch!=10 && Ch!=13) continue if (Ch==10) NL++ if (Ch==13) CR++ X += Math.max(Math.floor((j-xj-2)/Mx), 0) ; xj = j } // In principle, not quite right, as MSIE wraps at whitespace return X + Math.max(NL, CR) } function ShoGen(A) { // see ShoFFF var St = "", Len = A.length, j = 0, Vis = 1, Arg, LC = 0 while (Len>0) { Arg = A[j++] if (!Arg) { Vis = 0 ; continue } if (Arg.join) Arg = "[\n" + Arg.join("\n,\n") + "\n]" // ?? 2006-10-29 ?? Arg = ShoTrim(Arg.toString()) St += Arg ; if (Vis) LC += ShoLinCnt(Arg, BoxW) if (j==Len) break St += "\n\n" ; LC += Vis } return {Str:St, Cnt:LC} }

PopBtn & PopThis

Display code in a new window :-

function PopThis(btn) { // Executed by PopBtn buttons var Obj = ShoGen(btn.btnargs) // Height and Width values need improving var Wndw = window.open("", "X"+ +new Date(), "height=" + (16*Obj.Cnt+30) + ",width=" + (8*BoxX+20) + ",resizable,scrollbars") Wndw.document.write( // leading spaces for Opera " <pre>\n", SafeHTML(Obj.Str), "\n<\/pre>") Wndw.document.close() /* DU */ } function PopBtn() { // Call with ArgList to generate button document.write("<input type=button value='Pop Code'", " onClick='PopThis(this)'> ") var inputs = document.getElementsByTagName('input') // MH var Btn = inputs[inputs.length - 1] Btn.btnargs = arguments return Btn }

function PopBtns() { // Make demo for this page PopBtn(PopBtn) PopBtn(SafeHTML, PopThis, 0, PopBtn) PopBtn("Height test.", "I have yet to discover how to allow for font height/width.", "A","A","A","A","A","A","A","A","A","A","A","A","A", "A","A","A","A","A","A","A","A","A","A","A","A","A", "End.") }

Output to Window

function PageString(Site, Title, Owner, Body) { // OK by TIDY return '<!DOCTYPE HTML PUBLIC' + ' "-//W3C//DTD HTML 4.01 Transitional//EN"\n' + ' "http://www.w3.org/TR/html4/strict.dtd">\n' + '<HTML lang="en">\n<HEAD>\n' + '<META HTTP-EQUIV="Content-Type"' + ' CONTENT="text/html; charset=ISO-8859-1">\n' + '<TITLE>' + Site + ' -\n ' + Title + '\n - ' + Owner + '<\/TITLE>\n<\/HEAD>\n<BODY>\n' + '&copy; J R Stockton, www.merlyn.demon.co.uk, generated ' + new Date().toUTCString() + '\n<hr>\n' + Body + "\n\n<hr>\n<\/BODY>\n</\HTML>\n"} function NewPage(Title, Body) { // Same window, new content document.writeln(PageString(Site, Title, Owner, Body)) document.close() } function FreshPage(Title, Body) { // New window and content var Wndw = window.open("", "X"+new Date().getTime()) var Site = "Merlyn", Owner = "J R Stockton" // not inherited Wndw.document.writeln(PageString(Site, Title, Owner, Body)) Wndw.document.close() }

Source View Advice

function eIVSF() { Depikt(47, 2, " For the code, view the source of this page,\n" + " and any include files which it calls.") }

Marking Links

See at Link Markings.

function Cuffs() { var ThisPage, ThisSite, J, DLJ, HREF ThisPage = location.href.replace(/#.*/, "") ThisSite = location.protocol + "//" + location.hostname + "/" J = document.links.length ; while (J--) { DLJ = document.links[J] ; if (typeof DLJ.href != "string") continue // RikW c.l.j 20070719 HREF = DLJ.href // HREF = String(HREF) if (HREF.indexOf(ThisPage) == 0) DLJ.title = "." ; else if (HREF.indexOf(ThisSite) == 0) DLJ.title = "+" ; else if (HREF.indexOf("http://") == 0) DLJ.title = "#" ; else DLJ.title = "*" } }

Get XML HTTP Object

OK?

function getXMLHTTPobj() { // adapted from http://jibbering.com/2002/4/httprequest.html var XMLhttp = false /*@cc_on @*/ /*@if (@_jscript_version >= 5) // JScript gives us Conditional compilation, we can cope with old // IE versions and security blocked creation of the objects. try { XMLhttp = new ActiveXObject("Msxml2.XMLHTTP") } catch (e) { try { XMLhttp = new ActiveXObject("Microsoft.XMLHTTP") } catch (E) { XMLhttp = false } } @end @*/ if (!XMLhttp && typeof XMLHttpRequest!='undefined') { try { XMLhttp = new XMLHttpRequest() } catch (e) { XMLhttp = false } } if (!XMLhttp && window.createRequest) { try { XMLhttp = window.createRequest() } catch (e) { XMLhttp = false } } return XMLhttp }

ReFormatsCode

function ReFormatsCode() { var Bad // Warns where needed if (Bad = !/\*/.test(function(){/**/})) document.writeln("<div class=CAN>This browser reformats ", "displayed script functions, omitting comment.<\/div>") TPCV() ; return Bad }

ListLinks

function ListLinks() { var LINKS = [], DL = document.links, L = DL.length, J, T="", X for (J=0 ; J<L ; J++) LINKS.push(DL[J].href.replace(/#.*/, "")) LINKS.sort() J = 0 ; while (J<LINKS.length) { X = LINKS[J] if (X==T) LINKS.splice(J, 1) ; else J++ // de-dupe T = X } LINKS.splice(0, 0, "Automatic List of Links on This Page", "") return LINKS.join("\n") }

Contents of my file include2.js

function Caption2() { // JAVASCRIPT INCLUDE FILE - (c) J R Stockton >= 2006-12-24 // http://www.merlyn.demon.co.uk/include2.js }

var TestCounter = 1

Contents of my file include3.js

function Caption3() { // JAVASCRIPT INCLUDE FILE - (c) J R Stockton >= 2009-02-15 // http://www.merlyn.demon.co.uk/include3.js // Routines may be copied, but URL must not be linked to. // Needs, for LZ at least, include1.js }

Gregorian/Julian Difference

function GJdiff(A) { // N.B. A is Year, with March=3 and February=14 return (( (A/100|0) + 85)*3/4|0) - 65 }

Date/Time Output

// return Day of Week, accepts Sun=0 to Sun=7 function DoWstr(DoWk) { // Both JavaScript & ISO indexing return "SunMonTueWedThuFriSatSun".substr(3*DoWk, 3) }

// Methods added to Date Object // Method toSt :- function anonymous( ) { /* Date.toSt : omit parenthetical part */ return this.toString().replace(/( \(.+\))$/, '') } // Method ISOlocaltimeStr :- function anonymous( ) { /* Date.ISOlocaltimeStr hh:mm:ss */ with (this) return LZ(getHours())+':'+LZ(getMinutes())+':'+LZ(getSeconds()) } // Method USlocaltimeStr :- function anonymous( ) { /* Date.USlocaltimeStr hh:mm:ss xM */ var H with (this) return LZ( 1+((H=getHours())+11)%12 )+':'+ LZ(getMinutes())+':'+ LZ(getSeconds())+[' AM',' PM'][+(H>11)] } // Method ISOlocaldateStr :- function anonymous( ) { /* Date.ISOlocaldateStr YYYY-MM-DD */ with (this) return ZeroTo(getFullYear(),4)+'-'+LZ(getMonth()+1)+'-'+LZ(getDate()) } // Method ISOlocalDTstr :- function anonymous( ) { /* Date.ISOlocalDTstr YYYY-MM-DD hh:mm:ss */ with (this) return ISOlocaldateStr()+' '+ISOlocaltimeStr() } // Method utcYMDstr :- function anonymous( ) { /* Date.utcYMDstr YYYY-MM-DD */ with (this) return ZeroTo(getUTCFullYear(),4) + '-' + LZ(getUTCMonth()+1) + '-' + LZ(getUTCDate()) } // Method utcHMSstr :- function anonymous( ) { /* Date.utcHMSstr hh:mm:ss */ with (this) return LZ(getUTCHours()) + ':' + LZ(getUTCMinutes()) + ':' + LZ(getUTCSeconds()) } // Method utcDTstr :- function anonymous( ) { /* Date.utcDTstr YYYY-MM-DD hh:mm:ss */ with (this) return utcYMDstr() + ' ' + utcHMSstr() } // Method utcDYMDHMSstr :- function anonymous( ) { /* Date.utcDYMDHMSstr Xxx, YYYY-MM-DD hh:mm:ss */ with (this) return DoWstr(getUTCDay())+', '+utcDTstr() } // Method utcDDstr :- function anonymous( ) { /* Date.utcDDstr YYYY-MM-DD Xxx */ with (this) return utcYMDstr()+' '+DoWstr(getUTCDay()) } // Method YMDDstr :- function anonymous( ) { /* Date.YMDDstr YYYY-MM-DD Xxx */ with (this) return ISOlocaldateStr() + ' ' + DoWstr(getDay()) } // Method TZstr :- function anonymous( ) { /* Date.TZstr +-hh:mm */ var X, Y, Z ; with (this) { X = getTimezoneOffset() ; Y = Math.abs(X) ; Z = Y % 60 ; Y = (Y-Z)/60 ; return (X>0?'-':'+') + LZ(Y) + ':' + LZ(Z) } }

// Array [Y M D] to String YYYY-MM-DD function YMDto8601(A) { var S = "-" return A[0] + S + LZ(A[1]) + S + LZ(A[2]) }

Date/Time Input

function ParseDate(S) { // Permit ISO DateSeps, caveat Y<100 return new Date( S.replace(/-/g, "/") ) } function ParseWithUTC(S) { return ParseDate( S + " UTC" ) } function ValidDate(y, m, d) { // m = 0..11 ; y m d integers, y!=0 with (new Date(y, m, d, 6)) // 6 for Opera 9.2x return (getMonth()==m && getDate()==d) /* was y, m */ } function DateGood(y, m, d) { var D // m = 1..12 ; y m d ints, y!=0 with (D=new Date(y, --m, d)) return (getMonth()==m && getDate()==d) ? D : NaN } function ReadISO8601date(Q) { var T // adaptable for other layouts if ((T = /^(\d+)([-\/])(\d\d)(\2)(\d\d)$/.exec(Q)) == null) { return -2 } // bad format for (var j=1; j<=5; j+=2) T[j] = +T[j] // some use needs numbers if (!ValidDate(T[1], T[3]-1, T[5])) { return -1 } // bad value return [ T[1], T[3], T[5] ] }

CMJD functions

MJD 0 = 1858-11-17 GMT, CMJD 0 = 1858-11-17 local;
MJD 40587 = 1970-01-01 GMT = JavaScript day 0.
See at Day Counts.

function CMJDtoDob(CMJD) { // local time; CMJD 0 = 1858-11-17 local return new Date(1858, 10, 17 + CMJD) } function YMDtoCMJD(y, m, d) { // m = 1..12 return 40587 + Date.UTC(y, m-1, d)/864e5 } function CMJDtoYMD(CMJD) { with (new Date((CMJD-40587)*864e5)) { return [getUTCFullYear(), getUTCMonth()+1, getUTCDate()] } } // These are not meant for dates before 0000-03-01 :- function YMDzuCMJD(y, m, d) { // Fast. if (m<3) { m += 12 ; y-- } // Initial m *must* be in 1..12 return -678973 + d + (((153*m-2)/5)|0) + // 153 = 13 + 5*28 (1461*y>>2) - ((y/100)|0) + ((y/400)|0) } function CMJDzuYMD(CMJD) { var Y=0, M=0, t, d = CMJD + 678881 // 0000-03-01 : Julian, add 2 t = (( (4*(d+36525))/146097 )|0) - 1 // Gregorian Added Rules Y += 100*t ; d -= 36524*t + (t>>2) t = (( (4*(d+366))/1461 )|0) - 1 // Julian Rules Y += t ; d -= 365*t + (t>>2) M = ( (5*d+2)/153 )|0 // 153=5*28+13 months from March, M = 0... d -= ((2+M*153)/5)|0 // remove full months, d = 0... if (M > 9) { M -= 12 ; Y++ } return [Y, M+3, ++d] }

Weeks

Day of Week Routine

function ZelDoW(y, m, d) { // Sun = 0 if (m<3) { m += 12 ; y-- } return (2 + d + (((13*m-2)/5)|0) + // y + ((y/4)|0) - ((y/100)|0) + ((y/400)|0) ) % 7 } // <20060127 ((5*y)>>2) - ((y/100)|0) + ((y/400)|0) ) % 7 }

function YMD2YWD(y, m, d) { // ISO 8601 WkNo. m=1..12 var ms1d = 864e5, ms7d = 7*ms1d var DC3 = Date.UTC(y, m-1, d+3)/ms1d // an Absolute Day Number var DoW = 1 + (DC3+7777777)%7 var AWN = Math.floor(DC3/7) // an Absolute Week Number var Wyr = new Date(AWN*ms7d).getUTCFullYear() // return [Wyr, AWN - Math.floor(Date.UTC(Wyr, 0, 0)/ms7d), DoW ] } // 2007-04-03 : Firefox 2.0.0.3-14 is bad for d<1 !!! return [Wyr, AWN - Math.floor(Date.UTC(Wyr, 0, 7)/ms7d)+1, DoW ] } function CMJDtoYWD(CMJD) { // cf. Calendar FAQ 2.7, Stefan Potthast var d4, L, d1, WeekNumber, Bodge, DoW // Bodge, DoW added by JRS CJD = CMJD + 2400001 ; DoW = CJD % 7 d4 = (CJD+31741 - DoW) % 146097 % 36524 % 1461 // 0..1460 L = +(d4==1460) // was L = (d4/1460)|0 d1 = ((d4-L) % 365) + L WeekNumber = ((d1/7)|0) + 1 // ISO 8601 Bodge = CJD - 7*(WeekNumber-26) // mid-year Bodge = ((Bodge/365.2425)|0) - 4712 return [Bodge, WeekNumber, 1+DoW] } function YWDtoCMJD(YWD) { var CJD, y // By JRS 2005-02-23+ y = YWD[0]-1 // for CJD of Jan 4, modified from YMDzuCMJD CJD = 1721429 + (1461*y>>2) - ((y/100)|0) + ((y/400)|0) CJD -= CJD%7 // Round down to Monday; CJD 0 is Monday. CJD += YWD[1]*7 + +YWD[2] - 8 // Contributions of W and D return CJD - 2400001 /* ISO 8601 */ }

function UKtaxWNstr(y, m, d) { var dd, fy = y // m = 1..12 if (m*32+d<134) fy-- dd = (Date.UTC(y, m-1, d) - Date.UTC(fy, 3, 6))/864e5 return 'UK Revenue & Customs:' + ' Year ' + fy + ' week ' + LZ(Math.floor(dd/7)+1) + ' day ' + (dd%7+1) + ';' } function UKtaxMNstr(y, m, d) { var yy = y, mm = m // m = 1..12 if (d<6) mm-- if (mm<4) { yy-- ; mm += 12 } return ' Year ' + yy + ' month ' + LZ(mm-3) + '.' }

Calendar Parts

function UTCMonthLen(y, m) { // m = 0..11 // 20080604 return new Date(Date.UTC(y, m+1, 1, -9)).getUTCDate() } function LeapYr(y) { if (y%4) return false if (y%100) return true ; return !(y%400) } function Suffix(j) { return "thstndrd". substr("01230000000000000000012300000001".charAt(j)*2,2) }

Summer Time

function TimeChangeDates(YYYY) { // Detect OS settings var Ton, Tof, JanOff, JulOff, TonMin, TonMax, TofMin, TofMax, K with (new Date(0)) { setFullYear(YYYY, 0, 1) // allows YYYY<1000 TonMin = TofMin = getTime() ; JanOff = getTimezoneOffset() setMonth(6) ; JulOff = getTimezoneOffset() if (JanOff == JulOff) { return [0,0] } setMonth(12) ; TonMax = TofMax = getTime() var Min = Math.min(JanOff, JulOff) var Max = Math.max(JanOff, JulOff) Ton = Tof = (TonMin + TofMax)/2 for (K=0; K<22; K++) { setTime(Ton) ; if (getTimezoneOffset() != Max) { TonMax = Ton ; Ton = (TonMin+Ton)/2 } else { TonMin = Ton ; Ton = (Ton+TonMax)/2 } setTime(Tof) ; if (getTimezoneOffset() != Min) { TofMax = Tof ; Tof = (TofMin+Tof)/2 } else { TofMin = Tof ; Tof = (Tof+TofMax)/2 } } } Ton = Math.round(Ton/6e4)*6e4 ; Tof = Math.round(Tof/6e4)*6e4 return {Spring:Ton, Autumn:Tof} }

For Timing Code

function TimeFunc(Fns, N) { var Fn, J, K, D0, D1, St, T = new Date() St = "TimeFunc: " + N + " Loops\n\nms\tTimes" for (J in Fns) { St += "\n" ; Fn = Fns[J] ; if (!Fn) continue K = N ; D0 = new Date() ; while (K--) Fn(K) ; D1 = new Date() St += (D1-D0) + "\t" + NameFunc(Fn) } alert(St + "\n\nOverall: " + (new Date() - T) + " ms.") }

Contents of my file include4.js

function Caption4() { // JAVASCRIPT INCLUDE FILE - (c) J R Stockton >= 2010-02-23 // http://www.merlyn.demon.co.uk/include4.js // Routines may be copied, but URL must not be linked to. }

function dashTo(X2, Y2, Ptrn) { // segment of dasked line set // X2 Y2 : X & Y to go TO ; internal X1 Y1 to go FROM // Ptrn as [6,4, 1,4] // mark-space pairs indexed by Seg // supply Ptrn only for the first point of a dashed line set if (Ptrn) { this.Obj = {Patn:Ptrn, Seg:0, Phs:0, X1:X2, Y1:Y2} ; return } var XDis, YDis, Dist, X, More, T, Ob = this.Obj XDis = X2 - Ob.X1 // DeltaX YDis = Y2 - Ob.Y1 // DeltaY Dist = Math.sqrt(XDis*XDis + YDis*YDis) // length this.save() this.translate(Ob.X1, Ob.Y1) this.rotate(Math.atan2(YDis, XDis)) this.moveTo(0, 0) ; X = 0 // Now dash pattern from 0,0 to Dist,0 do { T = Ob.Patn[Ob.Seg] // Full segment X += T - Ob.Phs // Move by unused seg More = X < Dist // Not too far? if (!More) { Ob.Phs = T - (X - Dist) ; X = Dist } // adjust Ob.Seg%2 ? this.moveTo(X, 0) : this.lineTo(X, 0) if (More) { Ob.Phs = 0 ; Ob.Seg = ++Ob.Seg % Ob.Patn.length } } while (More) Ob.X1 = X2 ; Ob.Y1 = Y2 this.restore() }

Contents of my file rndg-inc.js

function CaptionR() { // JAVASCRIPT INCLUDE FILE - (c) J R Stockton >= 2009-09-26 // http://www.merlyn.demon.co.uk/rndg-inc.js // Common functions specific to Rounding tests // Routines may be copied, but URL must not be linked to. }

Rounding Testers

function SetRndCases() { // Function defines RndCases as Global RndCases = [ // Actual test case numbers for this page :- 0.0, 0.003, 0.007, 0.07, 0.70, 0.77499, 0.77501, 3.965, 3.995, 7, 777, 999.995, 7.3e25, NaN, Infinity, null, undefined, 2.22222e20 ] } function SubRnd(Fn, Sgn) { var J, St, Sg = +Sgn, T St = '\n&bull; ' + Sgn.charAt(0) + 'Case[] : ' for (J = 0 ; J < RndCases.length ; J++) { T = RndCases[J] if (T != undefined && T != null) T *= Sg if (J%6==5) St += '\n&nbsp; ' St += '"' + Fn(T, 2, 2) + '" ' } return St } function TryRnd(Fn) { var K, St St = "(RndCases[], 2, 2) :" + SubRnd(Fn, "+1") + SubRnd(Fn, "-1") + "\nSteps of 0.005 from 12.290 to 12.410 :\n" for (K = 12290 ; K <= 12410 ; K += 5) { if (K%50==0) St += "\n" St += Fn(K/1000, 2, 2) + " " } St += "\nBankers' ? : " for (K = -875 ; K <= 875 ; K += 250) St += Fn(K/1000, 2, 2) + " " return St } function TestF(Fn, p) { var FnN = NameFunc(Fn), S2 = '', S3 = '' if (FDS>0) document.writeln('<pre>', FnN, TryRnd(Fn), '<\/pre>') document.write('<form><pre class=TRY>', FnN, '( ', '<input type=text name=InA size=12> ') if (p>1) { document.write(', &nbsp;<input type=text name=InB size=2> ') S2 = ', +InB.value' } if (p>2) { document.write(', &nbsp;<input type=text name=InC size=2> ') S3 = ', +InC.value' } document.write(') <input type=button value="="', ' onClick="Ans.value='+FnN+'(InA.value'+S2+S3+')">', ' <input type=text name=Ans size=24 readonly>', '<br> <script>PopBtn(RndCases.toString()', '.replace(",,,", ",null,undefined,"))', '.value="Cases"<\/script>', // 20090923 ' &nbsp; <input type=button value="cf.toF" onClick="cfToF('+FnN+')">', '<\/pre><\/form>') }

// These have been replaced :- function OldSigFigNum(X, N) { // returns a Number var p = Math.pow(10, N-Math.ceil(Math.log(Math.abs(X))/Math.LN10)) return isFinite(p) ? Math.round(X*p)/p : X } function OldSigFigExp(X, N) { // N<22 , returns a String if (X==0) return OldSigFigExp(1, N).replace(/\+1/, ' 0') var p = Math.floor(Math.log(Math.abs(X))/Math.LN10) if (!isFinite(p)) return X return (X>0?'+':"") + String( Math.round(X*Math.pow(10, N-p-1))).replace(/(\d)/, "$1.") + (p>=0?"e+":"e-") + LZ(Math.abs(p)) }

Contents of my file estr-inc.js

function CaptionE() { // JAVASCRIPT INCLUDE FILE - (c) J R Stockton >= 2009-04-19 // http://www.merlyn.demon.co.uk/estr-inc.js // Easter Routines, except Zeller // See estrcalc.htm and estr-bcp.htm // Routines may be copied, but URL must not be linked to. // Uses Div & Mod from include1.js }

Easter Utilities

// DoM is Day-of-March, 22..56 function YMDobjToDoM(Obj) { // {Y,M,D} to DayOfMarch return (Obj.M-3)*31 + Obj.D } function YMDobjToISO(Obj) { // {Y,M,D} to "Y*-MM-DD" with (Obj) return Y + "-" + LZ(M) + "-" + LZ(D) } function YDoMtoISO(Year, Day) { var Mth = 3 if (Day>31) { Mth = 4 ; Day -= 31 } return Year + '-0' + Mth + '-' + LZ(Day) } function DoMtoMonDD(DM) { return DM>31 ? "Apr "+LZ(DM-31) : "Mar "+DM } function YDoMtoYMonDD(Y, DM) { return Y + " " + DoMtoMonDD(DM) }

Easter Functions

function EGREaster(Yr) { // Gregorian - E G Richards, Algorithm P var AA = Math.floor(Yr / 100) var BB = AA - Math.floor(AA / 4) var CC = Yr % 19 var DD = (15 + 19*CC + BB - Math.floor((AA + 1 - Math.floor((AA+8) / 25)) / 3)) % 30 var EE = DD - Math.floor((CC+11*DD) / 319) var DM = 22 + EE + (140004 - (Yr + Math.floor(Yr / 4))%7 + BB - EE) % 7 var EMo = 3 + Math.floor(DM / 32) var EDy = 1 + (DM-1) % 31 return {Y:Yr, M:EMo, D:EDy} } function USNOEaster(y) { // http://aa.usno.navy.mil/faq/docs/easter.html var Mf = Math.floor, c, n, k, i, j, l, m, d c = Mf(y / 100) n = y - 19 * Mf( y / 19 ) k = Mf(( c - 17 ) / 25) i = c - Mf(c / 4) - Mf(( c - k ) / 3) + 19 * n + 15 i = i - 30 * Mf( i / 30 ) i = i - Mf( i / 28 ) * ( 1 - Mf( i / 28 ) * Mf( 29 / ( i + 1 ) ) * ( Mf( 21 - n ) / 11 ) ) j = y + Mf(y / 4) + i + 2 - c + Mf(c / 4) j = j - 7 * Mf( j / 7 ) l = Math.round(i - j) m = 3 + Mf(( l + 40 ) / 44) d = l + 28 - 31 * Mf( m / 4 ) return {Y:y, M:m, D:d} } function CDWFEaster(year) { // http://www.davros.org/misc/easter.html Clive Feather var a, b, c, d, e, f, g, h, j, k, m, month, date a = year%19 b = Math.floor(year/100) ; c = year%100 d = Math.floor( b/4) ; e = b%4 f = Math.floor( c/4) ; g = c%4 h = Math.floor((8*b+13)/25) j = (19*a+b-d-h+15)%30 m = Math.floor((a+11*j)/319) k = (2*e+2*f-g-j+m+32)%7 month = Math.floor((j-m+k+90)/25) date = (j-m+k+19+month)%32 return {Y:year, M:month, D:date} } function CFAQEaster(year) { // Calendar FAQ var G, C, H, I, J, L G = year % 19 C = Div(year,100) H = (C - Div(C,4) - Div(8*C+13,25) + 19*G + 15) % 30 I = H - Div(H,28)*(1 - Div(29,H+1)*Div(21-G,11)) J = (year + Div(year,4) + I + 2 - C + Div(C,4)) % 7 L = I - J EasterMonth = 3 + Div(L+40,44) EasterDay = L + 28 - 31*Div(EasterMonth,4) return {Y:year, M:EasterMonth, D:EasterDay} /* L + 28 */ } function HenkEaster(year) { // Henk Reints var A, B, C, D, E, F, G A = year % 19 + 1 // Golden Number (Meton) B = Div(year, 100) + 1 // Century C = Div((3 * B), 4) - 12 // Greg-Julian Leap Diff D = Div((8 * B + 5), 25) - 5 // to adjust Meton E = Div((year * 5), 4) - 10 - C // day-of-week F = ( (11 * A + 20 + D - C) % 30 + 30) % 30 // the double % protects against F < 0 for large years F += (F == 24 || (F == 25 && A > 11)) // Epact G = 44 - F // a Full Moon if (G < 21) G += 30 // Paschal Full Moon return G + 7 - (E + G) % 7 /* return Day-of-March */ }

// Easter after the Book of Common Prayer function GoldenNumber(Yr) { return Mod(Yr, 19) + 1 } function SunNumAll(Y) { // In lieu of Table I ; perpetual Greg. Y = Mod(Y, 400) // to 0..399 Y += ((Y/4)|0) - ((Y/100)|0) return 6 - (Y+6)%7 /* 0-6 matches Sunday Letter A-G */ } function BCPcypher(Yr) { var CD = Div(Yr, 100) return Mod( Div(3*(CD+1), 4) - Div((13+CD*8), 25) + 23 , 30 ) } function PFMfromTableIII(GN, CY) { var TR TR = (11*GN - 3) % 30 // top row entry for GN DM = 21 + (30 + CY - TR) % 30 // descend column to CY if (DM + +(GN>11) > 31+18) DM-- // adjust for split row return DM /* Day-of-March */ } function SundayAfterPFM(DM, SN) { // plus 1..7 days to Sunday, J & G return DM + 1 + (60+SN-DM)%7 /* Day-of-March */ } function BCPAllEaster(YR) { // cf DemoCalc, modular var GN, CY, SN, DM GN = GoldenNumber(YR) SN = SundayNumber(YR) CY = BCPcypher(YR) DM = PFMfromTableIII(GN, CY) return SundayAfterPFM(DM, SN) /* Day-of-March */ } function JRSEaster(YR) { // cf BCPAllEaster, years in +-9E15 var GN, CY, SN, DM, xx GN = Mod(YR, 19) + 1 // GN = GoldenNumber xx = Div(YR, 100) // CY = BCPcypher CY = Mod( Div(3*(xx+1), 4) - Div((13+xx*8), 25) + 23, 30 ) YR = Mod(YR, 400) // to 0..399 xx = 6 + YR + ((YR/4)|0) - ((YR/100)|0) SN = 6 - xx%7 // Sunday Number 0-6 gives Sunday Letter A-G DM = 21 + (3 + CY + 19*GN)%30 ; DM -= ((GN>11) + DM > 49) // PFM return DM + 1 + (60+SN-DM)%7 /* Day-of-March */ } function jrsEaster(YR) { // Fast JRSEaster, unsigned 32-bit year var gn, xx, cy, DM gn = YR % 19 // gn ~ GoldenNumber xx = (YR/100)|0 cy = ((3*(xx+1)/4)|0) - (((13+xx*8)/25)|0) // cy ~ BCPcypher xx = ( 6 + YR + ((YR/4)|0) - xx + ((YR/400)|0) ) % 7 DM = 21 + (gn*19 + cy + 15)%30 ; DM -= ((gn>10) + DM > 49) // PFM return DM + 1 + (66-xx-DM)%7 /* Day-of-March */ }

Contents of my file zell-inc.js

For The Calendrical Works of Rektor Chr. Zeller : The Day-of-Week and Easter and associated pages.

function CaptionZ() { // JAVASCRIPT INCLUDE FILE - (c) J R Stockton >= 2008-11-11 // http://www.merlyn.demon.co.uk/zell-inc.js // DoWkTest and EasterTest are called by zel-188(2,3,5,6).htm // CodeLinks is called by those and zeller-c.htm // Gpro188x are used by zeller-c.htm ; are reduced Cvt188x // ZEG188x also used by zeller-c.htm ; zel-188x.htm use all 188x } function DoMtoISOdate(MarDay) { var Mth = 3, Day = MarDay if (Day>31) { Mth = 4 ; Day -= 31 } return 'Year-0' + Mth + '-' + LZ(Day) }

CodeLinks

function CodeLinks(X) { document.writeln('<p>', '<a href="view-source:'+this.location+'">View Source<\/a>, ', '<a href="view-source:http://www.merlyn.demon.co.uk/', 'zell-inc.js">View Include File<\/a> (contains functions), ', '<a href="js-nclds.htm#Zinc">', 'Include File Page<\/a> (shows functions)') if (X) document.writeln('<p>Automated Gregorian tests', ' are at <a href="zeller-c.htm#ToI">zeller-c.htm<\/a>.<\/p>' ) }

Day-of-Week Form

function DoWkTest(ZPYr) { with (new Date()) var TryD = getFullYear() + " " + LZ(getMonth()+1) + " " + LZ(getDate()) document.writeln( '<form name=FD', ZPYr, ' action="#">', '<div class=TRY style="margin: 0 auto 0 auto; width: 68ex;">', '<div class=CEN>', '<b>JavaScript Day-of-Week Tests - ', ZPYr, '<\/b><\/div><hr>', 'Y M D : <input type=text name=inp size=12 value="', TryD, '"> ', ' &nbsp; <input type=button name=Conv value="Convert" onClick= ', ' "var X = CvtYYYY(', ZPYr, ', inp.value) ;', ' Un.value = X[0] ; Pr.value = X[1] ; Dy.value = X[2] ">', '&nbsp; The input date is not numerically validated.<br>', '<input type=text name=Un size=40 readonly> &nbsp; As published', '<br><input type=text name=Pr size=40 readonly>', ' &nbsp; Protected against <i>MOD 7<\/i> error<br> Gregorian,', ' by JavaScript : <input type=text name=Dy size=6 readonly>', '<hr>Check all days in ', '<input type=text name=Rnge value="1995-2025" size=10>', ' (opens a new window or tab)', '<br>for <tt>Gpro<\/tt> value : ', // '<input type=button value="Juln" onClick="AllDays(this.form, ', ZPYr, ', 0)"> ', '<input type=button value="Greg" onClick="AllDays(this.form, ', ZPYr, ', 1)"> ', ' &nbsp; &nbsp; for <i>MOD 7<\/i> : ', '<input type=button value="Juln" onClick="Bad7Days(this.form, ', ZPYr, ', 0)"> ', '<input type=button value="Greg" onClick="Bad7Days(this.form, ', ZPYr, ', 1)"> ', '<\/div><\/form>' ) /* Writes form which calls Cvt188x & */ } function ZDoWk(S, v) { return ' ' + S + ': ' + v + ' ' + DName[v] } function CvtYYYY(YYYY, SS) { var B, y, m, q, Ansr = ['?', '?'] B = /^(\d+)\D+(\d+)\D+(\d+)$/.test(SS) if (B) with (RegExp) { y = +$1 ; m = +$2 ; q = +$3 // date with (new Date(0)) { setFullYear(y, m-1, q) ; var JavDay = (getDay()+1)%7 } window["Cvt"+YYYY](y, m, q) // sets globals Ansr = [ [$1,$2,$3] + ';' + ZDoWk('Jdow', Jdow) + ZDoWk('Gdow', Gdow), [$1,$2,$3] + ';' + ZDoWk('Jpro', Jpro) + ZDoWk('Gpro', Gpro), JavDay + ' ' + DName[JavDay] ] } return Ansr }

Easter Form

function EasterTest(ZPYr) { var TryY = (new Date()).getFullYear() document.writeln('<form name=FE', ZPYr, ' action="#">', '<div class=TRY style="margin: 0 auto 0 auto; width: 29ex;">', '<div class=CEN>', '<b>JavaScript Easter Test - ', ZPYr, '<\/b><\/div><hr>', 'Year &nbsp;', '<input type=text name=Inp size=8 value="', TryY, '"> &nbsp; ', '<input type=button name=Conv value=" Go " onClick= ', ' " Ju.value = DoMtoISOdate(ZEJ', ZPYr, '(+Inp.value)) ;', ' Gr.value = DoMtoISOdate(ZEG', ZPYr, '(+Inp.value)) ;', ' CF.value = YMDobjToISO(EGREaster(+Inp.value)) "><br>', '<input type=text name=Ju size=13 readonly> &nbsp; Julian<br>', '<input type=text name=Gr size=13 readonly> &nbsp; Gregorian<br>', '<input type=text name=CF size=13 readonly> &nbsp;', ' Good Greg.', '<\/div><\/form>') /* Writes form to call ZEJ188x & ZEG188x */ }

Year Tests

function ZellerUserTest(ZY) { // e.g. ZY=1886 document.writeln("<p>Test form for any of four Papers :-<\/p>") DoWkTest(ZY) ; EasterTest(ZY) PopBtn(window["Cvt"+ZY], window["Gpro"+ZY]) PopBtn(window["ZEJ"+ZY], window["ZEG"+ZY]) PopBtn(AllDays, Bad7Days) CodeLinks(1) }

Tests for Zeller's Examples

function EasterExample(Cal, EFn, Year) { document.writeln("Easter ", Year, " = ", DoMtoISOdate(EFn(Year)), " ", Cal) } function DoWeekExample(Cal, CvtN, Y, M, D) { CvtN(Y, M, D) var X = Cal.charAt(0)=="J" ? Jpro : Gpro document.writeln("Day-of-Week ", Y, "-", LZ(M), "-", LZ(D), " = ", X, " ", DName[X], " ", Cal) }

1882 Paper

function Cvt1882(y, m, q) { var J, e, k, A if (m<3) { m = m+12 ; y = y-1 } J = Math.floor(y/100) ; k = y%100 ; e = J%4 ; A = k+4 Gdow = (q + Math.floor((m+1)*26/10) + k + Math.floor(k/4) - 2*e) % 7 Gpro = (q + Math.floor((m+1)*26/10) + k + Math.floor(k/4) + 5*e) % 7 Jdow = (q + Math.floor((m+1)*26/10) + A + Math.floor(A/4) - J ) % 7 Jpro = (q + Math.floor((m+1)*26/10) + A + Math.floor(A/4) + 6*J) % 7 } function Gpro1882(y, m, q) { var J, e, k if (m<3) { m = m+12 ; y = y-1 } J = Math.floor(y/100) ; k = y%100 ; e = J%4 Gpro = (q + Math.floor((m+1)*26/10) + k + Math.floor(k/4) + 5*e) % 7 return Gpro } function ZEJ1882(Yr) { var a, b, d, k = Yr%100, J = (Yr-k)/100, ko4 = Math.floor(k/4) a = (k + 5*J) % 19 b = ( 19*a+15 ) % 30 d = (b + k + ko4 - J) % 7 ; if (d<0) d+=7 // correction 20070515 return 28 + b - d } function ZEG1882(Yr) { var a, b, d, h, k = Yr%100, J = (Yr-k)/100, ko4 = Math.floor(k/4), Jo4 = Math.floor(J/4), e = J%4 a = (k + 5*J) % 19 h = J - Jo4 - Math.floor( (8*J+13)/25 ) b = ( 19*a+15 + h ) % 30 // d = (b + k + ko4 + 2 - 2*e) % 7 // can the arg be neg? yes d = (b + k + ko4 + 2 + 5*e) % 7 if (d==0) { if ((b==29) || ( b==28 && a>10)) d = 7 } return 28 + b - d }

1883 Paper

function Cvt1883(y, m, q) { var I, e, k if (m<3) { m = m+12 ; y = y-1 } I = Math.floor(y/100) ; e = I%4 ; k = y%100 ; Jdow = (q + Math.floor((m+1)*26/10) + k + Math.floor(k/4) - (I+2))%7 Jpro = (q + Math.floor((m+1)*26/10) + k + Math.floor(k/4) +6*I-2 )%7 Gdow = (q + Math.floor((m+1)*26/10) + k + Math.floor(k/4) - 2*e) % 7 Gpro = (q + Math.floor((m+1)*26/10) + k + Math.floor(k/4) + 5*e) % 7 } function Gpro1883(y, m, q) { var I, e, k if (m<3) { m = m+12 ; y = y-1 } I = Math.floor(y/100) ; e = I%4 ; k = y%100 ; Gpro = (q + Math.floor((m+1)*26/10) + k + Math.floor(k/4) + 5*e) % 7 return Gpro } function ZEJ1883(Yr) { var a, b, d, k = Yr%100, I = (Yr-k)/100, ko4 = Math.floor(k/4) a = (k + 5*I) % 19 b = ( 19*a+15 ) % 30 d = (b + k + ko4 - I) % 7 ; if (d<0) d+=7 // correction 20070515 return 28 + b - d } function ZEG1883(Yr) { var a, b, d, h, k = Yr%100, I = (Yr-k)/100, ko4 = Math.floor(k/4), Io4 = Math.floor(I/4), e = I%4 a = (k + 5*I) % 19 h = I - Io4 - Math.floor( (8*I+13)/25 ) b = ( 19*a+15 + h ) % 30 // d = (b + k + ko4 + 2 - 2*e) % 7 // can arg be neg? yes // +2 d = (b + k + ko4 + 2 + 5*e) % 7 // +2 if (d==0) { if ((b==29) || ( b==28 && a>10)) d = 7 } return 28 + b - d }

1885 Paper

function Cvt1885(y, m, q) { var J, e, K if (m<3) { m = m+12 ; y = y-1 } J = Math.floor(y/100) ; e = J%4 ; K = y%100 ; Gdow = (q + Math.floor((m+1)*26/10) + K + Math.floor(K/4) - 2*e) % 7 Gpro = (q + Math.floor((m+1)*26/10) + K + Math.floor(K/4) + 5*e) % 7 Jdow = (q + Math.floor((m+1)*26/10) + K + Math.floor(K/4) - (J+2))%7 Jpro = (q + Math.floor((m+1)*26/10) + K + Math.floor(K/4) + 6*J+5 )%7 } function Gpro1885(y, m, q) { var I, e, K if (m<3) { m = m+12 ; y = y-1 } I = Math.floor(y/100) ; e = I%4 ; K = y%100 ; Gpro = (q + Math.floor((m+1)*26/10) + K + Math.floor(K/4) + 5*e) % 7 return Gpro } function ZEJ1885(Yr) { var a, b, d, K = Yr%100, J = (Yr-K)/100, Ko4 = Math.floor(K/4) a = Yr % 19 b = ( 19*a+15 ) % 30 d = (b + K + Ko4 - J) % 7 ; if (d<0) d+=7 // correction 20070515 return 28 + b - d } function ZEG1885(Yr) { var a, b, d, g, K = Yr%100, J = (Yr-K)/100, Ko4 = Math.floor(K/4), Jo4 = Math.floor(J/4), e = J%4 a = (K + 5*J) % 19 g = J - Jo4 - Math.floor( (8*J+13)/25 ) b = ( 19*a+15 + g ) % 30 // d = (b + K + Ko4 + 2 - 2*e) % 7 // can the arg be neg? // +2 d = (b + K + Ko4 + 2 + 5*e) % 7 // can the arg be neg? // +2 if (d==0) { if ((b==29) || ( b==28 && a>10)) d = 7 } return 28 + b - d }

1886 Paper

function Cvt1886(y, m, q) { var J, e, K if (m<3) { m = m+12 ; y = y-1 } J = Math.floor(y/100) ; e = J%4 ; K = y%100 ; Jdow = (q + Math.floor((m+1)*26/10) + K + Math.floor(K/4) + 5 - J) % 7 Jpro = (q + Math.floor((m+1)*26/10) + K + Math.floor(K/4) + 5 + 6*J) % 7 Gdow = (q + Math.floor((m+1)*26/10) + K + Math.floor(K/4) + Math.floor(J/4) - 2*J) % 7 Gpro = (q + Math.floor((m+1)*26/10) + K + Math.floor(K/4) + Math.floor(J/4) + 5*J) % 7 } function Gpro1886(y, m, q) { var J, e, K if (m<3) { m = m+12 ; y = y-1 } J = Math.floor(y/100) ; e = J%4 ; K = y%100 ; // Gpro = (q + Math.floor((m+1)*2.6) + // K + Math.floor(K/4) + 5*e) % 7 Gpro = (q + Math.floor((m+1)*26/10) + K + Math.floor(K/4) + Math.floor(J/4) + 5*J) % 7 return Gpro } function ZEJ1886(Yr) { var a, b, d, K = Yr%100, J = (Yr-K)/100, Ko4 = Math.floor(K/4) a = Yr % 19 b = ( 19*a+15 ) % 30 d = (b + K + Ko4 - J) % 7 ; if (d<0) d+=7 // correction 20070515 return 28 + b - d } function ZEG1886(Yr) { var a, b, d, g, K = Yr%100, J = (Yr-K)/100, Ko4 = Math.floor(K/4), Jo4 = Math.floor(J/4), e = J%4 a = (5*J + K) % 19 g = J - Jo4 - Math.floor((8*J+13)/25) b = ( 19*a+15 + g ) % 30 d = (b + K + Ko4 + Jo4 + 2 + 5*J) % 7 // arg be neg? // +2 +5* if (d==0) { if ((b==29) || ( b==28 && a>10)) d = 7 } return 28 + b - d }

For main Zeller page

function RunD(y1, y2, Orl, ZZ, EX) { if ((y2-y1)>[10,1][+Orl]) if (!confirm('This may take some time - OK?')) return ZZ.value = '-' ; EX.value = ' Working' setTimeout("RunDates("+y1+", "+y2+", "+Orl+")", 10) } function RunDates(y1, y2, Orl) { var D = new Date(0), T=' ' var A, X0, X2, X3, X5, X6, J, JS, Errs = 0, Err, S, y, m, q with (document.forms['Frm1']) { EX.value = ' Date Good 1882 1883 1885 1886 Err?' for ( J=y1 ; J<=y2 ; J++ ) { window.status = J for ( D.setFullYear(J, 0, 1) ; D.getFullYear()==J ; D.setDate(D.getDate()+1) ) { with (D) { X0 = (D.getDay() + 1)%7 y = getFullYear() ; m = getMonth()+1 ; q = getDate() } X2 = Gpro1882(y, m, q) X3 = Gpro1883(y, m, q) X5 = Gpro1885(y, m, q) X6 = Gpro1886(y, m, q) Err = (X2!=X0) || (X3!=X0) || (X5!=X0) || (X6!=X0) if (Err) { Errs++ } if (Orl || Err ) { S = '\n' + D.ISOlocaldateStr() + T + X0 + T + X2 + T + X3 + T + X5 + T + X6 EX.value += S + (Err ? ' ****' : '' ) } } } ZZ.value = ' Years '+y1+'-'+y2+' done, errors '+ Errs } }

function RunE(y1, y2, Orl, F) { if ((y2-y1)>[500,250][+Orl]) if (!confirm('This may take some time - OK?')) return with (F) { ZZ.value = '-' ; EX.value = ' Working' } setTimeout("RunEaster("+y1+", "+y2+", "+Orl+")", 10) } function RunEaster(y1, y2, Orl) { var Errs = 0, Err, S, X0, X2, X3, X5, X6, J, JS, T=' ' with (document.forms['Frm2']) { EX.value = ' Year EGRP 1882 1883 1885 1886 Err?' for ( J=y1 ; J<=y2 ; J++ ) { window.status = J X0 = YMDobjToDoM(EGREaster(J)) X2 = ZEG1882(J) X3 = ZEG1883(J) X5 = ZEG1885(J) X6 = ZEG1886(J) Err = (X2!=X0) || (X3!=X0) || (X5!=X0) || (X6!=X0) if (Err) { Errs++ } if (Orl || Err ) { JS = J + '' ; while (JS.length<5) JS = ' ' + JS S = '\n' + JS + T + X0 + T + X2 + T + X3 + T + X5 + T + X6 EX.value += S + (Err ? ' ****' : '' ) } } ZZ.value = ' Years '+y1+'-'+y2+' done, errors '+ Errs } }