function eval_and_fix(formula){
var input_number;
input_number = eval(formula) + '';
// If scientific notation, return
if ((input_number.indexOf("e") > -1) || (input_number.indexOf("E") > -1)){
return input_number;
}
// if an integer, return
if (input_number.indexOf('.') == -1){
return input_number;
}
// Seperate and round to 12
var first, last, split_at;
split_at = input_number.indexOf('.');
first = input_number.substr(0,split_at);
last = input_number.substr(split_at, input_number.length - split_at);
//last = Math.round(last * 1000000000000);
//last /= 1000000000000;
// round to only 3 instead
last = Math.round(last * 1000);
last /= 1000;
return parseInt(first) + last;
}
function parseinputweight2vol(inputamount, inputdensity) {
var teststring;
var density = document.getElementById('density').value;
var quantity = document.getElementById('quantity').value;
if ( quantity.length == 0 ) {
alert ("Please enter the amount you want to convert!");
return false;
}
if ( isNaN(parseFloat(quantity)) ) {
alert ("The entered amount isn't a number!");
return false;
}
if ( parseFloat(quantity) <= 0 ) {
alert ("The amount have to be positive!");
return false;
}
if ( density.length == 0 ) {
alert ("Please enter the density or choose the substance from the list!");
return false;
}
if ( isNaN(parseFloat(density)) ) {
alert ("The entered density isn't a number!");
return false;
}
if ( parseFloat(density) <= 0 ) {
alert ("The density have to be positive!");
return false;
}
return true;
}
function calcweight2vol() {
if ( parseinputweight2vol() == false ) {
return false;
}
var inunit = document.getElementById('inunit');
var inunittext = inunit.options[inunit.selectedIndex].text;
var inunitval = parseFloat(inunit.value);
var outunit = document.getElementById('outunit');
var outunittext = outunit.options[outunit.selectedIndex].text;
var outunitval = parseFloat(outunit.value);
var densunit = document.getElementById('densunit');
var densunittext = densunit.options[densunit.selectedIndex].text;
var densamount = parseFloat(document.getElementById('density').value);
var densvalue = densamount / parseFloat(densunit.value);
var quantity = parseFloat (document.getElementById('quantity').value);
var amount = quantity;
var substancetext = "";
var result;
// first we convert a given amount of substance to grams
if ( inunitval > 0 ) {
amount = amount * inunitval;
} else {
amount = amount * (-inunitval) * densvalue;
}
// then we convert the grams to given output unit
if ( outunitval > 0 ) {
result = amount / outunitval;
} else {
result = amount / densvalue / (-outunitval);
}
result = eval_and_fix(result);
if ( outunitval*inunitval < 0 ) {
substancetext = "For substance with density of " + densamount + " " + densunittext;
}
document.getElementById('result').value = quantity + " " + inunittext + " = " + result + " " + outunittext;
if (substancetext != ""){
document.getElementById('substancemessage').innerHTML = substancetext;
}
}
function copydensity() {
resetForm();
if (document.getElementById('substance').selectedIndex == -1){
return;
}
document.getElementById('density').value=eval_and_fix(
parseFloat(document.getElementById('substance').value)
*
parseFloat(document.getElementById('densunit').value));
}
function checkcopydensity() {
if (document.getElementById('substance').selectedIndex == -1){
return;
}
copydensity();
}
function resetdensityForm() {
document.getElementById('substance').selectedIndex = -1;
resetForm();
}
function resetForm() {
document.getElementById('result').value = "";
document.getElementById('substancemessage').innerHTML = " ";
}
//-->
...more cool gadgets
]]>