Wissenschaftlicher Rechner
Dieser erste Teil des Scripts kommt in den Headbereich

<SCRIPT LANGUAGE="JavaScript">

<!-- Begin
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 sqrt(form) {
form.display.value = Math.sqrt(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
}
// End -->
</SCRIPT>
Der zweite Teil kommt in den Bodybereich, dort wo Sie diesen Rechner haben wollen.
<FORM>
<table width="264" bgcolor="#D4D4D4" border="1" cellpadding="5" cellspacing="3">
<tr>
<td colspan="5" height="35">
<div align="center">
<input name="display" value="0" size=25>
</div>
</td>
</tr>
<tr>
<td>
<div align="center">
<input type="button" value=" exp " onClick="if (checkNum(this.form.display.value)) {
exp(this.form) }">
</div>
</td>
<td>
<div align="center">
<input type="button" value=" 7 " onClick="addChar(this.form.display, '7')">
</div>
</td>
<td>
<div align="center">
<input type="button" value=" 8 " onClick="addChar(this.form.display, '8')">
</div>
</td>
<td>
<div align="center">
<input type="button" value=" 9 " onClick="addChar(this.form.display, '9')">
</div>
</td>
<td>
<div align="center">
<input type="button" value=" / " onClick="addChar(this.form.display, '/')">
</div>
</td>
</tr>
<tr>
<td>
<div align="center">
<input type="button" value=" ln " onClick="if (checkNum(this.form.display.value)) {
ln(this.form) }">
</div>
</td>
<td>
<div align="center">
<input type="button" value=" 4 " onClick="addChar(this.form.display, '4')">
</div>
</td>
<td>
<div align="center">
<input type="button" value=" 5 " onClick="addChar(this.form.display, '5')">
</div>
</td>
<td>
<div align="center">
<input type="button" value=" 6 " onClick="addChar(this.form.display, '6')">
</div>
</td>
<td>
<div align="center">
<input type="button" value=" * " onClick="addChar(this.form.display, '*')">
</div>
</td>
</tr>
<tr>
<td>
<div align="center">
<input type="button" value=" sqrt " onClick="if (checkNum(this.form.display.value)) {
sqrt(this.form) }">
</div>
</td>
<td>
<div align="center">
<input type="button" value=" 1 " onClick="addChar(this.form.display, '1')">
<t/d> </div>
<td>
<div align="center">
<input type="button" value=" 2 " onClick="addChar(this.form.display, '2')">
</div>
</td>
<td>
<div align="center">
<input type="button" value=" 3 " onClick="addChar(this.form.display, '3')">
</div>
</td>
<td>
<div align="center">
<input type="button" value=" - " onClick="addChar(this.form.display, '-')">
</div>
</td>
</tr>
<tr>
<td>
<div align="center">
<input type="button" value=" sq " onClick="if (checkNum(this.form.display.value)) {
square(this.form) }">
</div>
</td>
<td>
<div align="center">
<input type="button" value=" 0 " onClick="addChar(this.form.display, '0')">
</div>
</td>
<td>
<div align="center">
<input type="button" value=" . " onClick="addChar(this.form.display, '.')">
</div>
</td>
<td>
<div align="center">
<input type="button" value=" +/- " onClick="changeSign(this.form.display)">
</div>
</td>
<td>
<div align="center">
<input type="button" value=" + " onClick="addChar(this.form.display, '+')">
</div>
</td>
</tr>
<tr>
<td>
<div align="center">
<input type="button" value=" ( " onClick="addChar(this.form.display, '(')">
</div>
</td>
<td>
<div align="center">
<input type="button" value=" cos " onClick="if (checkNum(this.form.display.value)) {
cos(this.form) }">
</div>
</td>
<td>
<div align="center">
<input type="button" value=" sin " onClick="if (checkNum(this.form.display.value)) {
sin(this.form) }">
</div>
</td>
<td>
<div align="center">
<input type="button" value=" tan " onClick="if (checkNum(this.form.display.value)) {
tan(this.form) }">
</div>
</td>
<td>
<div align="center">
<input type="button" value=" ) " onClick="addChar(this.form.display, ')')">
</div>
</td>
</tr>
<tr>
<td colspan="5">
<div align="center">
<input type="button" value=" Clear " onClick="this.form.display.value = 0 ">
<input type="button" value=" Back Space " onClick="deleteChar(this.form.display)">
<input type="button" value=" Enter " name="enter"
onClick="if (checkNum(this.form.display.value)) {
compute(this.form) }">
</div>
</td>
</tr>
</table>
</FORM>