/* speedclc.js -- computes scale speeds -- March 29, 2005 the form controls are: clcd is input control for distance (in inches), clct is input control for time (in seconds), clcs is select controlscale (text - 1:x) clcv is output in scale mph (for report a set of mphs for 1,2, ... 12 secs) access is thru the form element id 'clc' created by john russell, ve3ll@rac.ca */ /* validated with JSlint 2005 03 29 */ cf=3600 / (5280*12);// inch per sec to mph sf=null;time=null;dist=null;vel=null; function roundoff(x,y) { scale=Math.pow(10,y);return Math.round(x * scale)/scale;} function about(id) { alert('SpeedCalc version 4.1 written by John Russell.\n' + 'Feel free to copy speedclc.js for your own use.'); document.getElementById(id+'d').focus();} function clrForm(id) { sf=null;time=null;dist=null;vel=null; document.getElementById(id+'d').value=" "; document.getElementById(id+'t').value=" "; document.getElementById(id+'v').value=" "; document.getElementById(id+'d').focus();} function testDist(id) { if (dist.length < 1) { alert("You must set distance!"); document.getElementById(id+'d').focus();return false;} if (isNaN(dist) === true) { alert("Distance must be a number!"); document.getElementById(id+'d').focus();return false;} if (dist < 0.1) { alert("Distance must be positive!"); document.getElementById(id+'d').focus();return false;} return true;} function testTime(id) { if (time.length < 1) { alert("You must set time!"); document.getElementById(id+'t').focus();return false;} if (isNaN(time) === true) { alert("Time must be a number!"); document.getElementById(id+'t').focus();return false;} if (time < 0.1) { alert("Time must be positive!"); document.getElementById(id+'t').focus();return false;} return true;} function testVel(id) { if (vel.length < 1) { alert("You must set speed!"); document.getElementById(id+'v').focus();return false;} if (isNaN(vel) === true) { alert("Speed must be a number!"); document.getElementById(id+'v').focus();return false;} if (vel < 0.1) { alert("Speed must be positive!"); document.getElementById(id+'v').focus();return false;} return true;} function distx(id) { // validate before math time=document.getElementById(id+'t').value; vel=document.getElementById(id+'v').value; el=document.getElementById(id+'s'); sc=el.options[el.selectedIndex].text; sf=sc.substring(sc.indexOf(":") + 1, sc.length); if (testTime(id)=== false) {return;} if (testVel(id)=== false) {return;} document.getElementById(id+'d').value=roundoff(vel*time/(cf*sf),1); document.getElementById(id+'d').focus();} function speed(id) { // validate before math dist=document.getElementById(id+'d').value; time=document.getElementById(id+'t').value; el=document.getElementById(id+'s'); sc=el.options[el.selectedIndex].text; sf=sc.substring(sc.indexOf(":") + 1, sc.length); if (testDist(id)=== false) {return;} if (testTime(id)=== false) {return;} document.getElementById(id+'v').value=roundoff(dist/time*(cf*sf),1); document.getElementById(id+'d').focus();} function timex(id) { // validate before math dist=document.getElementById(id+'d').value; vel=document.getElementById(id+'v').value; el=document.getElementById(id+'s'); sc=el.options[el.selectedIndex].text; sf=sc.substring(sc.indexOf(":") + 1, sc.length); if (testDist(id)=== false) {return;} if (testVel(id)=== false) {return;} document.getElementById(id+'t').value=roundoff(dist/vel*(cf*sf),1); document.getElementById(id+'d').focus();} function report(id) { dist=document.getElementById(id+'d').value; if (testDist(id)=== false) {return;} el=document.getElementById(id+'s'); sc=el.options[el.selectedIndex].text; sf=sc.substring(sc.indexOf(":") + 1, sc.length); msg='\n'; msg+='Speed Chart for '+sc+' Scale<\/title>\n'; msg+='<style type="text/css">\nbody {background:linen}\n'; msg+='h1,h3, div {text-align:center}\n'; msg+='table {margin:auto}\n<\/style>\n'; msg+='<meta http-equiv="Content-Type" content="text/html;charset=iso-8859-1">\n'; msg+='<\/head><body><h1>Speed Chart for '+sc+' Scale<\/h1>\n'; msg+='<h3>Timed distance is '+dist+' inches<\/h3>\n<div><table>\n'; msg+='<tr><th>Time [sec]<\/th><th>Speed [mph]<\/th><\/tr>'; for (rt=1 ;rt <=12;rt++) { spd=roundoff(dist/rt*(cf*sf),1);// calc for one unit msg+='<tr><th>'+rt+'<\/th><th>'+spd+'</th><\/tr>\n'; } msg+='<\/table><\/div><\/body><\/html>\n';document.write(msg);}