The form below performs the SCTID Check-Digit computation and checking. It also identifies the namespace element of an identifier. Below the form is an expandable box including the JavaScript code used to perform these computations.
<style>
p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 12.0px Helvetica}
span.s1 {color: #021da7}
span.s2 {color: #f9975e}
span.s3 {color: #ff9450}
span.s4 {color: #ab4500}
span.s5 {color: #a7a400}
table.sctid {border-width: 6px; border-color: #0080ff; border-collapse: collapse; border-style: ridge;}
td.sctid {border-width: 3px; border-color: #0080ff; border-collapse: collapse; padding: 6px; border-style: ridge;}
</style>
<form action="" name="form">
<table class="sctid" border="1" width="441">
<tr>
<td class="sctid" width="212" height="25"> Partial Identifier <br/>(without check-digit) </td>
<td class="sctid" width="115" height="25">
<input name="num" size="18"/>
</td>
<td class="sctid" width="92" height="25">
<input onclick="VerhoeffCompute()" type="button" value="Compute"/>
</td>
</tr>
<tr>
<td class="sctid" width="212" height="35"> SNOMED CT Identifier </td>
<td class="sctid" width="115" height="35">
<input name="numcd" size="18"/>
</td>
<td class="sctid" width="92" height="35">
<input onclick="VerhoeffCheck()" type="button" value="Check"/>
</td>
</tr>
<tr>
<td class="sctid" width="212" height="23"> Result of check </td>
<td class="sctid" width="115" height="23" colspan="2" id="out"> </td>
</tr>
<tr>
<td class="sctid" width="212" height="23"> Component type </td>
<td class="sctid" width="115" height="23" colspan="2" id="component"> </td>
</tr>
<tr>
<td class="sctid" width="212" height="23"> Namespace </td>
<td class="sctid" width="115" height="23" colspan="2" id="extnamespace"> </td>
</tr>
</table>
<p style="margin-left: 0; margin-right: 0"> This Verhoeff checking part of this code was based
on a webpage at: </p>
<ul>
<li>
<a href="http://www.augustana.ab.ca/~mohrj/algorithms/checkdigit.html">
http://www.augustana.ab.ca/~mohrj/algorithms/checkdigit.html </a>
</li>
</ul>
</form>
<script>
var FnF = new Array();
FnF[0] = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
FnF[1] = [1, 5, 7, 6, 2, 8, 3, 0, 9, 4];
for ( var i = 2; i < 8; i++ )
{
FnF[i] = [,,,,,,,,,];
for ( var j = 0; j < 10; j++ )
FnF[i][j] = FnF[i - 1][FnF[1][j]];
}
var Dihedral = new Array(
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9],
[1, 2, 3, 4, 0, 6, 7, 8, 9, 5],
[2, 3, 4, 0, 1, 7, 8, 9, 5, 6],
[3, 4, 0, 1, 2, 8, 9, 5, 6, 7],
[4, 0, 1, 2, 3, 9, 5, 6, 7, 8],
[5, 9, 8, 7, 6, 0, 4, 3, 2, 1],
[6, 5, 9, 8, 7, 1, 0, 4, 3, 2],
[7, 6, 5, 9, 8, 2, 1, 0, 4, 3],
[8, 7, 6, 5, 9, 3, 2, 1, 0, 4],
[9, 8, 7, 6, 5, 4, 3, 2, 1, 0] );
var InverseD5 = new Array(0, 4, 3, 2, 1, 5, 6, 7, 8, 9 );
function VerhoeffCheck()
{
var check = 0;
var IdValue = document.form.numcd.value;
document.getElementById("out").innerText = "";
document.getElementById("out").setAttribute("style","color:red;");
document.getElementById("component").innerText ="Invalid partition";
document.getElementById("component").setAttribute("style","color:green;");
document.getElementById("extnamespace").innerText ="No namespace";
document.getElementById("extnamespace").setAttribute("style","color:red;");
for ( var i=IdValue.length-1; i >=0; i-- )
check = Dihedral[check][FnF[(IdValue.length-i-1) % 8][IdValue.charAt(i)]];
if ( check != 0 ) { document.getElementById("out").innerText = "Check-digit ERROR"; }
else if (IdValue.length < 6) {document.getElementById("out").innerText = "SCTID too short";}
else if (IdValue.length > 18) {document.getElementById("out").innerText = "SCTID too long";}
else {document.getElementById("out").innerText = "Check-digit OK";
document.getElementById("out").setAttribute("style","color:green;");
switch (IdValue.substr(IdValue.length-3,2))
{
case "00":
document.getElementById("component").innerText ="Concept";
document.getElementById("extnamespace").innerText ="International";
break;
case "01":
document.getElementById("component").innerText ="Description";
document.getElementById("extnamespace").innerText ="International";
break;
case "02":
document.getElementById("component").innerText ="Relationship";
document.getElementById("extnamespace").innerText ="International";
break;
case "03":
document.getElementById("component").innerText ="Subset (RF1)";
document.getElementById("extnamespace").innerText ="International";
break;
case "04":
document.getElementById("component").innerText ="Cross Map Set (RF1)";
document.getElementById("extnamespace").innerText ="International";
break;
case "05":
document.getElementById("component").innerText ="Cross Map Target (RF1)";
document.getElementById("extnamespace").innerText ="International";
break;
case "10":
document.getElementById("component").innerText ="Concept";
document.getElementById("extnamespace").innerText =IdValue.substr(IdValue.length-10,7);
break;
case "11":
document.getElementById("component").innerText ="Description";
document.getElementById("extnamespace").innerText =IdValue.substr(IdValue.length-10,7);
break;
case "12":
document.getElementById("component").innerText ="Relationship";
document.getElementById("extnamespace").innerText =IdValue.substr(IdValue.length-10,7);
break;
case "13":
document.getElementById("component").innerText ="Subset (RF1)";
document.getElementById("extnamespace").innerText =IdValue.substr(IdValue.length-10,7);
break;
case "14":
document.getElementById("component").innerText ="Cross Map Set (RF1)";
document.getElementById("extnamespace").innerText =IdValue.substr(IdValue.length-10,7);
break;
case "15":
document.getElementById("component").innerText ="Cross Map Target (RF1)";
document.getElementById("extnamespace").innerText =IdValue.substr(IdValue.length-10,7);
break;
default:
document.getElementById("component").setAttribute("style","color:red;");
}
if (document.getElementById("extnamespace").innerText=='International') {document.getElementById("extnamespace").setAttribute("style","color:green;");}
else if (IdValue.length>10) {document.getElementById("extnamespace").setAttribute("style","color:green;");}
else {document.getElementById("extnamespace").innerText="Invalid Namespace";
}
}
}
function VerhoeffCompute( )
{
var IdValue = document.form.num.value; var check = 0;
document.form.numcd.value= "";
for ( var i = IdValue.length-1; i >=0; i-- )
check = Dihedral[check][FnF[(IdValue.length-i) % 8][IdValue.charAt(i)]];
document.form.numcd.value = document.form.num.value + InverseD5[check];
VerhoeffCheck();
document.getElementById("out").innerText = "Computed check-digit";
}
</script> |
The source HTML and JavaScript code for this form is shown in 6.4.2 Check-digit Computation. |