//Manuel Villanueva
//November 20, 2003, Updated Feb 5, 2011

function pet_dose(form) {

var wt = form.wt.value;
var adult = form.adult.value;

//input dog weight in pounds
if (form.pet_option.selectedIndex == 0 && form.wt_option.selectedIndex ==0) {
var bsa = Math.pow(wt/2.2,0.67) * 10.1 / 100;
form.bsa.value = Math.round(100*bsa)/100;
form.dose.value = Math.round( 100 * (bsa / 1.73 * adult)) /100;
}

//input dog weight in kilograms
if (form.pet_option.selectedIndex == 0 && form.wt_option.selectedIndex ==1) {
var bsa = Math.pow(wt,0.67) * 10.1 / 100;
form.bsa.value = Math.round(100*bsa)/100;
form.dose.value = Math.round( 100 * (bsa / 1.73 * adult)) /100;
}  

//input cat weight in pounds
if (form.pet_option.selectedIndex == 1 && form.wt_option.selectedIndex ==0) {
var bsa = Math.pow(wt/2.2,0.67) * 10.4 / 100;
form.bsa.value = Math.round(100*bsa)/100;
form.dose.value = Math.round( 100 * (bsa / 1.73 * adult)) /100;
}

//input cat weight in kilograms
if (form.pet_option.selectedIndex == 1 && form.wt_option.selectedIndex ==1) {
var bsa = Math.pow(wt,0.67) * 10.4 / 100;
form.bsa.value = Math.round(100*bsa)/100;
form.dose.value = Math.round( 100 * (bsa / 1.73 * adult)) /100;
}

//if statements--
if((form.wt.value==null)||(form.wt.value=="")||(isNaN(form.wt.value))){
alert("Please enter a weight"  +"\n"+"Use numbers only" +"\n"+ "Use a period for decimal place");
form.wt.focus();
form.wt.select();
return false
}
//added feb 2 2011
if ((form.wt.value==null)||(isNaN(form.dose.value))){
alert("Please enter a human dose"  +"\n"+"Use numbers only" +"\n"+ "Use a period for decimal place");
form.adult.focus();
form.adult.select();
return false
}
}