CALCULATORS
Paste this Code between "<head" and "</head>"
<SCRIPT LANGUAGE="JavaScript">
function addChar(input, character) {
if(input.value
== null || input.value == "0")
input.value
= character
else
input.value
+= character
}
function cos(form) {
form.display.value
= Math.cos(form.display.value);
}
function sin(form) {
form.display.value
= Math.sin(form.display.value);
}
function tan(form) {
form.display.value
= Math.tan(form.display.value);
}
function sqrt(form) {
form.display.value
= Math.sqrt(form.display.value);
}
function ln(form) {
form.display.value
= Math.log(form.display.value);
}
function exp(form) {
form.display.value
= Math.exp(form.display.value);
}
function deleteChar(input) {
input.value
= input.value.substring(0, input.value.length - 1)
}
function changeSign(input) {
if(input.value.substring(0,
1) == "-")
input.value
= input.value.substring(1, input.value.length)
else
input.value
= "-" + input.value
}
function compute(form) {
form.display.value
= eval(form.display.value)
}
function square(form) {
form.display.value
= eval(form.display.value) * eval(form.display.value)
}
function checkNum(str) {
for
(var i = 0; i < str.length; i++) {
var
ch = str.substring(i, i+1)
if
(ch < "0" || ch > "9") {
if
(ch != "/" && ch != "*" && ch !=
"+" && ch != "-" && ch != "."
&&
ch != "(" && ch!= ")") {
alert("invalid
entry!")
return
false
}
}
}
return
true
}
</SCRIPT>
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