Excel addin, ZZMath.XLL

!!ATTENTION!! If you are in the state of Wisconsin, do not download my addin. I take no responsibility for it if you do as it is against my will and the state of Wisconsin shall have NO PERSONAL JURISDICTION over me. (explanation at bottom)

   I wrote a handy Microsoft Excel addin to experiment with number theory. It provides arbitrary precision arithmetic on integers upto 250 digits, and implements several routines of interest to number theorists. Try it out and let me know if you like it and/or have suggestions about it.

If you are not a resident of the state of Wisconsin, Click here to download the addin

To use, copy the file ZZMath.xll to your machine, start Excel, then choose 'File/Open' to open it (or if you always want it available when you start Excel choose Tools/Addins and add it there). Enter =ZPow(2, 500) in a cell for a quick demonstration. When passing large integers to the routine be sure to put them in quotes. The addin works on strings internally but Excel will translate numbers it can handle to strings for you as in the example above. I.e. If you enter =ZFactor(111111111111111111111111111111) you will get back "Z_Err" because Excel translates that 111... to 1.111...E+29. To properly work with those large numbers Excel can't, send them as strings, I.e. the following works correctly, =ZFactor("111111111111111111111111111111")

Try out the following to get started:

  • Enter =ZSub(ZPow(2, 200), 75) in cell A1.
  • Enter =ZSquareSum(A1) in cell A2.

    Note: You can find the various functions available in the addin and a short help description about each by choosing 'Insert Function' in Excel, choosing category 'ZMath' (scroll to bottom) and browsing the functions there.

    CLICK HERE FOR MORE DOCUMENTATION
    Silly Story.. (read below)

    Originally I had called my tool ZMath.xll, as it deals with integer (Z) arithmetic. However, I was shocked to receive an email recently from a lawyer (Eric S. Freibrun [efreibrun@msn.com]), stating I had to change it because his client (MathCorp) claims the ZMath trademark. I believe I have every right to name my files whatever I want, just as I can name my dog or cat whatever I want. However, I don't have time to consider it at this time. I may decide to switch the names back in the future out of principle, but for now I added a Z to call it ZZMath.xll.

    It's humorous actually, because I don't think the site was causing a problem with MathCorp's ZMath trademark before. However, since I'm aggravated by this I could potentially really stir some trouble hypothetically by creating a 'MathCorp's ZMath Sucks' web-site. Case law upholds such sites, See references on 'Bally Total Fitness Holding Corporation v. Andrew Faber'. I'm tempted to register a domain name to express my views, but it isn't worth my time at this juncture.

    Joe K. Crump | Number Theory Home