View source for APC Houses Javascript code snippet

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<html>
<textarea columns="30" rows="40">
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<SCRIPT LANGUAGE="JavaScript">
<!--

function compute(form) {

  PH=(form.nPh.value=="")? "0" : eval(form.nPh.value);
  ECL=(form.ne.value=="")? "0": eval(form.ne.value);
  AZ=(form.naz.value=="") ? "0" :eval(form.naz.value);

  with (Math) {  

    form.cusp1.value = sector(1, rad(PH), rad(ECL), rad(AZ));
    form.cusp2.value = sector(2, rad(PH), rad(ECL), rad(AZ));
    form.cusp3.value = sector(3, rad(PH), rad(ECL), rad(AZ));
    form.cusp4.value = sector(4, rad(PH), rad(ECL), rad(AZ));
    form.cusp5.value = sector(5, rad(PH), rad(ECL), rad(AZ));
    form.cusp6.value = sector(6, rad(PH), rad(ECL), rad(AZ));
    form.cusp7.value = sector(7, rad(PH), rad(ECL), rad(AZ));
    form.cusp8.value = sector(8, rad(PH), rad(ECL), rad(AZ));
    form.cusp9.value = sector(9, rad(PH), rad(ECL), rad(AZ));
    form.cusp10.value = sector(10, rad(PH), rad(ECL), rad(AZ));
    form.cusp11.value = sector(11, rad(PH), rad(ECL), rad(AZ));
    form.cusp12.value = sector(12, rad(PH), rad(ECL), rad(AZ));
  }
}

function exampledata(form) {
  document.form.nPh.value = "48.416667";
  document.form.ne.value = "23.456389";
  document.form.naz.value = "344.166667";
  document.form.cusp1.value = "";
  document.form.cusp2.value = "";
  document.form.cusp3.value = "";
  document.form.cusp4.value = "";
  document.form.cusp5.value = "";
  document.form.cusp6.value = "";
  document.form.cusp7.value = "";
  document.form.cusp8.value = "";
  document.form.cusp9.value = "";
  document.form.cusp10.value = "";
  document.form.cusp11.value = "";
  document.form.cusp12.value = "";
}

function resetform(form) {
  document.form.nPh.value = "";
  document.form.ne.value = "23.45";
  document.form.naz.value = "";
  document.form.cusp1.value = "";
  document.form.cusp2.value = "";
  document.form.cusp3.value = "";
  document.form.cusp4.value = "";
  document.form.cusp5.value = "";
  document.form.cusp6.value = "";
  document.form.cusp7.value = "";
  document.form.cusp8.value = "";
  document.form.cusp9.value = "";
  document.form.cusp10.value = "";
  document.form.cusp11.value = "";
  document.form.cusp12.value = "";
}

/* Utility functions and global variables */

var pi=Math.PI;

function rad(gr) { return pi * gr / 180; }
function gra(ra) { if (ra<0) ra=ra+2*pi; return Fmod((180 * ra / pi), 360); }

function Sgn(x) { return Math.floor(x/Math.abs(x)+.5) }
function Fmod(x,y) {return x-y*Math.floor(x/y) }
function Sin(x) { return Math.sin(x) }
function Cos(x) { return Math.cos(x) }
function Tan(x) { return Math.sin(x)/Math.cos(x) }
function ATan(x) { return Math.atan(x) }
function ATan2(x, y) { return Math.atan(Math.abs(x)/y)*Sgn(x)+pi*(y<0)}
function ASin(x) { return Math.asin(x) }
function ACos(x) { return Math.acos(x) }

<!-- A.P.C. houses (input ph, e, az in radians, output in degrees)-->
function sector(n, ph, ecl, az)
{
  var dasc, kv, a;
  
  kv   = ATan(Tan(ph) * Tan(ecl) * Cos(az)/(1 + Tan(ph) * Tan(ecl) * Sin(az)));
  dasc = ATan(Sin(kv) / Tan(ph));
  
  if (n<8) {a = kv + az + pi/2 + (n -  1) * (pi/2 - kv) / 3;}
  else     {a = kv + az + pi/2 + (n - 13) * (pi/2 + kv) / 3;}
  
  return gra(ATan2(Tan(dasc) * Tan(ph) * Sin(az) + Sin(a),
    Cos(ecl) * (Tan(dasc) * Tan(ph) * Cos(az) + Cos(a)) + Sin(ecl) * Tan(ph) * Sin(az - a)));
}

// done hiding from old browsers -->
</SCRIPT>

</HEAD>
<BODY onLoad="exampledata(); compute(document.form);">

<TABLE class="overlay" width="100%">
<TR><TD>

<BR>
<FORM NAME="form">

<UL>
<H3>
Enter the appropriate values here
</H3>
</UL>

<FONT size="+1">
<PRE>
     G.Lat  <INPUT TYPE="text" NAME="nPh"       SIZE=20>        <INPUT TYPE="button" VALUE="  Reset form  " OnClick="resetform(this.form)">
     E      <INPUT TYPE="text" NAME="ne"     SIZE=20>        <INPUT TYPE="button" VALUE=" Example data " OnClick="exampledata(this.form); compute(this.form);">
     ARMC   <INPUT TYPE="text" NAME="naz"      SIZE=20>        <INPUT TYPE="button" VALUE="   Calculate  " OnClick="compute(this.form)">
</PRE>
</FONT>

<UL>
<H3>
APC Cusps
</H3>
</UL>

<FONT size="+1">
<PRE>
     1      <INPUT TYPE="text" NAME="cusp1"      SIZE=20>   7    <INPUT TYPE="text" NAME="cusp7"      SIZE=20>
     2      <INPUT TYPE="text" NAME="cusp2"      SIZE=20>   8    <INPUT TYPE="text" NAME="cusp8"      SIZE=20>
     3      <INPUT TYPE="text" NAME="cusp3"      SIZE=20>   9    <INPUT TYPE="text" NAME="cusp9"      SIZE=20>
     4      <INPUT TYPE="text" NAME="cusp4"      SIZE=20>   10   <INPUT TYPE="text" NAME="cusp10"      SIZE=20>
     5      <INPUT TYPE="text" NAME="cusp5"      SIZE=20>   11   <INPUT TYPE="text" NAME="cusp11"      SIZE=20>
     6      <INPUT TYPE="text" NAME="cusp6"      SIZE=20>   12   <INPUT TYPE="text" NAME="cusp12"      SIZE=20>
     
</PRE>
</FONT>
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</textarea>
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