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DM 42
05-26-2017, 04:36 PM
Post: #61
RE: DM 42
(05-26-2017 12:52 PM)toml_12953 Wrote:  
(05-26-2017 07:34 AM)Paul Dale Wrote:  I'm fine with the 42S's behaviour. CPXRES and REALRES are required.

The question was more: should a calculator switch between real and complex mode automatically? It shouldn't unless told to. This works both ways: (0 + i)2 should give (-1, 0) not -1.
Maybe for you it shouldn't but for me, it should always give an answer in either the real or complex plane as appropriate. If I could pick only one method, I'd have the calculator always give a numeric answer whether real or complex. If I was working a real-world problem and saw a complex result, I'd know there was no real solution. If the calculator always reported an error when given real inputs, there would be no way of knowing what the actual answer was.

Tom L

That's exactly what CPXRES mode does: with real inputs, you get real results if they exist, and complex results if necessary; with complex inputs, you always get complex results. This is the default mode on the HP-42S and in Free42, and, I assume, DM42 as well.
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Messages In This Thread
DM 42 - Geoff Quickfall - 05-19-2017, 05:21 PM
RE: DM 42 - Dave Frederickson - 05-19-2017, 05:29 PM
RE: DM 42 - Dave Frederickson - 05-26-2017, 08:32 PM
RE: DM 42 - Massimo Gnerucci - 05-19-2017, 05:30 PM
RE: DM 42 - Ángel Martin - 05-19-2017, 05:53 PM
RE: DM 42 - Massimo Gnerucci - 05-19-2017, 06:08 PM
RE: DM 42 - Dan B - 05-19-2017, 08:58 PM
RE: DM 42 - Geoff Quickfall - 05-19-2017, 09:30 PM
RE: DM 42 - Luigi Vampa - 05-19-2017, 09:38 PM
RE: DM 42 - Namir - 05-20-2017, 01:07 AM
RE: DM 42 - 48GX - 05-24-2017, 11:37 AM
RE: DM 42 - Dave Britten - 05-24-2017, 01:27 PM
RE: DM 42 - matthiaspaul - 05-25-2017, 09:09 PM
RE: DM 42 - matthiaspaul - 05-26-2017, 12:18 AM
RE: DM 42 - matthiaspaul - 05-29-2017, 11:26 PM
RE: DM 42 - 48GX - 05-30-2017, 12:37 AM
RE: DM 42 - rprosperi - 05-30-2017, 02:21 AM
RE: DM 42 - grsbanks - 05-30-2017, 10:31 AM
RE: DM 42 - Logan - 05-24-2017, 11:38 AM
RE: DM 42 - HP-Collection - 05-24-2017, 12:15 PM
RE: DM 42 - Dave Frederickson - 05-24-2017, 03:58 PM
RE: DM 42 - Guenter Schink - 05-24-2017, 01:53 PM
RE: DM 42 - Ángel Martin - 05-26-2017, 01:36 PM
RE: DM 42 - Thomas Okken - 05-26-2017, 04:30 PM
RE: DM 42 - Guenter Schink - 05-26-2017, 04:53 PM
RE: DM 42 - Ángel Martin - 05-27-2017, 05:27 AM
RE: DM 42 - Logan - 05-24-2017, 04:32 PM
RE: DM 42 - Ángel Martin - 05-24-2017, 04:44 PM
RE: DM 42 - Vtile - 05-24-2017, 05:34 PM
RE: DM 42 - Guenter Schink - 05-24-2017, 06:42 PM
RE: DM 42 - Ángel Martin - 05-24-2017, 06:48 PM
RE: DM 42 - Vtile - 05-24-2017, 07:58 PM
RE: DM 42 - Thomas Okken - 05-24-2017, 11:25 PM
RE: DM 42 - Ángel Martin - 05-25-2017, 04:50 AM
RE: DM 42 - Thomas Okken - 05-25-2017, 11:31 AM
RE: DM 42 - Ángel Martin - 05-25-2017, 04:35 PM
RE: DM 42 - Thomas Okken - 05-25-2017, 06:16 PM
RE: DM 42 - matthiaspaul - 05-26-2017, 11:38 AM
RE: DM 42 - Hsilop - 05-24-2017, 08:25 PM
RE: DM 42 - Logan - 05-24-2017, 08:29 PM
RE: DM 42 - Vtile - 05-24-2017, 08:30 PM
RE: DM 42 - Hsilop - 05-24-2017, 09:05 PM
RE: DM 42 - Vtile - 05-24-2017, 09:08 PM
RE: DM 42 - Logan - 05-24-2017, 09:09 PM
RE: DM 42 - Vtile - 05-24-2017, 09:11 PM
RE: DM 42 - Paul Dale - 05-25-2017, 12:59 AM
RE: DM 42 - Thomas Okken - 05-25-2017, 02:13 AM
RE: DM 42 - Guenter Schink - 05-25-2017, 09:52 AM
RE: DM 42 - Paul Dale - 05-25-2017, 11:11 AM
RE: DM 42 - Ángel Martin - 05-25-2017, 04:31 PM
RE: DM 42 - toml_12953 - 05-25-2017, 05:15 PM
RE: DM 42 - Thomas Okken - 05-25-2017, 06:21 PM
RE: DM 42 - Paul Dale - 05-26-2017, 12:05 AM
RE: DM 42 - toml_12953 - 05-26-2017, 01:37 AM
RE: DM 42 - pier4r - 05-25-2017, 08:03 PM
RE: DM 42 - Thomas Okken - 05-25-2017, 10:57 PM
RE: DM 42 - Paul Dale - 05-26-2017, 03:51 AM
RE: DM 42 - Ángel Martin - 05-26-2017, 05:33 AM
RE: DM 42 - Thomas Okken - 05-26-2017, 07:24 AM
RE: DM 42 - toml_12953 - 05-26-2017, 07:41 AM
RE: DM 42 - toml_12953 - 05-26-2017, 07:33 AM
RE: DM 42 - Paul Dale - 05-26-2017, 07:34 AM
RE: DM 42 - toml_12953 - 05-26-2017, 12:52 PM
RE: DM 42 - Thomas Okken - 05-26-2017 04:36 PM
RE: DM 42 - toml_12953 - 05-26-2017, 07:37 PM
RE: DM 42 - AlexFekken - 05-26-2017, 10:24 AM
RE: DM 42 - Ángel Martin - 05-26-2017, 12:19 PM
RE: DM 42 - jch - 05-26-2017, 01:17 PM
RE: DM 42 - Thomas Okken - 05-28-2017, 08:57 PM
RE: DM 42 - rprosperi - 05-28-2017, 09:09 PM
RE: DM 42 - Thomas Okken - 05-28-2017, 09:47 PM
RE: DM 42 - rprosperi - 05-28-2017, 10:04 PM
RE: DM 42 - Thomas Okken - 05-28-2017, 10:24 PM
RE: DM 42 - rprosperi - 05-29-2017, 12:10 AM
RE: DM 42 - Thomas Okken - 05-29-2017, 01:30 AM
RE: DM 42 - rprosperi - 05-29-2017, 02:12 AM
RE: DM 42 - Massimo Gnerucci - 05-26-2017, 06:16 PM
RE: DM 42 - pier4r - 05-26-2017, 06:24 PM
RE: DM 42 - Thomas Okken - 05-26-2017, 06:56 PM
RE: DM 42 - Geoff Quickfall - 05-26-2017, 08:59 PM
RE: DM 42 - Dave Frederickson - 05-26-2017, 09:22 PM
RE: DM 42 - Geoff Quickfall - 05-26-2017, 09:44 PM
RE: DM 42 - matthiaspaul - 05-30-2017, 10:45 AM
RE: DM 42 - Massimo Gnerucci - 05-30-2017, 11:37 AM
RE: DM 42 - Guenter Schink - 05-30-2017, 12:24 PM
RE: DM 42 - Thomas Okken - 05-30-2017, 12:50 PM
RE: DM 42 - Ángel Martin - 05-30-2017, 04:44 PM
RE: DM 42 - Guenter Schink - 05-30-2017, 06:48 PM
RE: DM 42 - Ángel Martin - 05-30-2017, 07:47 PM



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