jquery determines two decimal places and automatically deletes the numbers after two decimal places_jquery

$("#fileds").find("input").blur(function(){
var value=$(this).val();
if(value == null || value == ''){
return false;
}
if(!isNaN(value)){
var userreg=/^[0-9] ([.]{1}[0 -9]{1,2})?$/;
if(userreg.test(value)){
if(parseInt(value).toString().length > 5){
$ (this).val("");
alertMsg("The entered integer must not be larger than 5 digits");
return false;
}
}else{
var numindex = parseInt (value.indexOf("."),10);
if(numindex == 0){
$(this).val("");
alertMsg("The entered number is not standardized" );
return false;
}
var head = value.substring(0,numindex);
var bottom = value.substring(numindex,numindex 3);
var fianlNum = head bottom;
$(this).val(fianlNum);

}
}else{
$(this).val("");
alertMsg("Please enter Number");
return false;
}
});