• Subject: Re: if statement brain cramp
  • From: Buck Calabro <kc2hiz@xxxxxxxxx>
  • Date: Wed, 27 Feb 2019 11:49:02 -0500
  • Autocrypt: addr=kc2hiz@xxxxxxxxx; keydata= mQGiBEcbaT4RBADqmM9OgXil65pjrxclJpxuAF6vraI3kkmJbEHb5ElL7EquHE3QDuFqFgIB 4NZLHDbVAh0AD5exAX+r+xg//UvtBc2k34HROnCpWTMnIOaSVhhVjpYEbZGLz6wfrRpu4Qyn 45iaKT4F0qcHo+0LrGQPef3xrFkUhxURgzY5zgo6+wCg/XjYJ155witPWB2CbNf6RAm9QT0D /jSp6YhvE3xPE12aBuRYM678JTbaQfuYv4HUfug1Wz/0zH5btfEihWVN4wbKaoQ/H/29v2TP /Lyh8XTVd3Z0rz4iaSD5fGicn81WPANBeIepLB8vpfEik6UhHpN1DJkz6Ryw2mgx8p53LhHV Ck4Jt0HP2TAl3f7QTXGFOiFzJwEqBACsHk/gFpKAHdv7n4vJoHqp0RNgOOyhnTThlulPilt6 tAaSe10FOrrugBuLMn7wXBANQ1ApmIb5yNjhYqPREj65OVv2MUbw8H2HnQs//Z6aodyR/kzU 2q2G9A/YFI1LL0m/gvaVbEj/wE0ybBgFkrcoEFeStkqS5HzLEFGUDFXhD7QfQnVjayBDYWxh YnJvIDxrYzJoaXpAZ21haWwuY29tPoiFBBMRAgBFAhsDBgsJCAcDAgQVAggDBBYCAwECHgEC F4AFAkcbdMokGGh0dHA6Ly9rZXlzZXJ2ZXIudmVyaWRpcy5jb206MTEzNzEvAAoJEN7KcclH umuRfngAoNXU6AXqyTR8FRuoXKBGS4k7bPUEAJ912WKSkjpCt0axjrq6j22e5XgWzbkCDQRH G2k+EAgAnLXJ9hOqedgsIYM3LuomBBNN+7WTFSVaJ3Rqz8XVZtJvLL0bIRAvpVK9L9rYXlCR cPAm0YNK6H2DR7sQxWlxEH4mWB+jTCTALpcVq+Kpfbw5qDdn+9DVMS7tBOchtTlPSGgdKgn7 sTObra8cHtX/ddTB6OLzHeTXr4PZbUwVeQdIStdwMmozKBQvgjXWKi1GiuYbwYkCM/zJEUCs J36BIE4li9xohJ5O4iKC20YVckMJfZLbn1a2gVgn6Re8C5ezNewT0qM8ZDCUNENWAxsU/c9J UCFQ2QcMU+25b84D5yPxnEKna5U9Fz2JjRjWy5ZKZx2+WhZj0r2Tw6/kGb28AwADBgf/WBsn JSMHxyVfg+LKLHpdANwa9jdrKOt2WjJbWOiJ9l7SmqD0oi3c22FFxRXKsFfjCikLk9wbLZKH SqqnOePvMMHqNcqQTSv7+ARjxnBH4g6dhqg+zmebKpt8zV2awQzYSSm4YY6IqzkWmPNAN7BU zUtSAfL4UU2PljTnT9m443aVCTXMne5l90HQv/gdJ121owg5KuGE6LodTpoR4hn9nbdKWtfY pDNoykvR+GN5y335yF2Zp/j6QgdxWezjou5Y3/6PUZLEsJagWe9hAcKb1eiO2bmg+1bFYu0T g5Mvb27nqfFeHHFysC7a7sXtxp/pqNLNDcK6j/7Th6vF7/n98YhJBBgRAgAJBQJHG2k+AhsM AAoJEN7KcclHumuR9SgAnRuJWHon4GP58xbqCiFR/jSUfvRgAJ47KZ1UNoXgdftoePnbrZu6 W+poEw==
  • List-archive: <https://archive.midrange.com/rpg400-l/>
  • List-help: <mailto:rpg400-l-request@lists.midrange.com?subject=help>
  • List-id: "RPG programming on the IBM i \(AS/400 and iSeries\)" <rpg400-l.lists.midrange.com>
  • List-post: <mailto:rpg400-l@lists.midrange.com>
  • List-subscribe: <https://lists.midrange.com/mailman/listinfo/rpg400-l>, <mailto:rpg400-l-request@lists.midrange.com?subject=subscribe>
  • List-unsubscribe: <https://lists.midrange.com/mailman/options/rpg400-l>, <mailto:rpg400-l-request@lists.midrange.com?subject=unsubscribe>

On 2/27/2019 11:35 AM, Joe Pluta wrote:
You've gotten all the specific answers you need, but I thought I'd chime
in with the more generalized approach. This is Boolean logic or more
precisely Boolean algebra (which is what got me into programming lo
those many decades ago).  The specific case is DeMorgan's law, which
states:

not (A and B) = (not A or not B)

A: SML010 <> 5
B: M1PLIN = *blanks

not A: SML010 = 5
not B: M1PLIN <> *blanks
(not A or not B): (SML010 = 5 or M1PLIN <> *blanks)

I use Boolean algebra all the time to simplify complex business logic
(especially IF statements that have grown over time).  A nice page for
it exists here:

https://www.ics.uci.edu/~pattis/ICS-31/lectures/simplify/lecture.html

Good reference.

Although more often applied to digital electronics than to software, the
general principles hold. If one is a visual learner, the graphical
depiction of logic gates might assist in digesting how De Morgan's laws
work with real-world problems.

Another tool that might be helpful is a Karnaugh map.
I don't need one often, but when I do...


As an Amazon Associate we earn from qualifying purchases.

This thread ...

Follow-Ups:
Replies:

Follow On AppleNews
Return to Archive home page | Return to MIDRANGE.COM home page

This mailing list archive is Copyright 1997-2021 by midrange.com and David Gibbs as a compilation work. Use of the archive is restricted to research of a business or technical nature. Any other uses are prohibited. Full details are available on our policy page. If you have questions about this, please contact [javascript protected email address].

Operating expenses for this site are earned using the Amazon Associate program and Google Adsense.