Sample Apfloat Applets

Arbitrary precision calculator applet
Unsigned Signed

Pi calculation applet
Single-thread Unsigned Signed
Multi-thread Unsigned Signed

There are some prerequisites to get them to run:

• You must have a Java 5.0 plugin or later. The Java Virtual Machine built-in to older versions of Internet Explorer and Netscape Navigator is not sufficient (they only support Java 1.1.x, which is too old). Get the plugin from the Java website or from Sun. Note that some new computers may already have the appropriate Java plugin installed.
• Set the Java plug-in to be the default for your browser. You can do this either when installing the plugin or later from the Control Panel.
• Unsigned applets are provided, but their calculation capabilities are limited by the available memory in your computer. You can be assured that these applets are safe to run, since the Java plugin will prevent the applets from doing anything potentially unsafe, like accessing your computer's file system.
• Also, signed applets are provided, which can use the full power of apfloat for calculations. They will need to create some temporary files on your disk. When you run these applets, they will display a security warning. Even the certificate is bogus; it's just a dummy certificate that isn't certified by any trusted authority. It's up to you to allow or prevent the applets from running... anyway the only unsafe thing they do is write temporary files to your disk. It's not any more unsafe than the command-line version of the apfloat calculation programs, if you would choose to download and run them instead.
• Both single-thread and multi-thread versions of the pi calculation applet are provided. The multi-thread version provides an advantage only if your computer has more than one processor. If you don't know how many processors your computer has, it probably has just one, and you should then use the single-thread version.

Tips for advanced users

• By default, Sun's Java plugin uses the client VM. You can use the server VM and get a free, roughly 40% performance boost. To do this, first download the latest Java SDK and install it. Then run e.g. the command:
  appletviewer -J-server http://www.apfloat.org/apfloat_java/applet/pi.html
• For more advanced users, the downloadable package includes a distributed pi calculation program that can use multiple computers to calculate pi. This is the most powerful version of the pi calculation program available, but you need to download and set it up manually.

Last updated: January 5th, 2006