plot error messages are completelly missing
- To: mathgroup at smc.vnet.net
- Subject: [mg116890] plot error messages are completelly missing
- From: john <j.f.b.payne at blueyonder.co.uk>
- Date: Thu, 3 Mar 2011 05:59:47 -0500 (EST)
Hello, Apologies if this isn't the proper way to submit, it seemed to be from http://smc.vnet.net/MathGroup.html This is a late reply on the subject which came up Sep 10 2007! Using Mathematica 8 recently, I was working with a complicated function, which I'd Plot[]ted. None of the results I was getting made sense. Eventually, I discovered that where the function appeared to be zero in the plot it was actually imaginary, and everything fell into place. I hadn't considered this possibility because I've been used to the Plot[] behaviour of version 5.2 (and previous versions) where error messages reported the function not being real. So, I strongly agree with Szabolcs comment that there should be a message for complex numbers/infinity. Personally, I think error messages should be on by default. I want to know when things are going wrong, and not be left believing misleading information. I suppose this is because I do research, so I don't just want a noise-free picture of things I already know. Anyway, thanks to Jason Martinez of Wolfram Technical Support for the following information. You can get error messages for complex numbers as follows: On[General::plnr] Plot[Sqrt[1 - x^2]^7, {x, 0, 2}, Method -> {"SuppressMessages" -> False}] This is still not default behaviour, but default behaviour is not a big issue, because of course, you can include in the init.m file On[General::plnr] SetOptions[Plot, Method->{"SuppressMessages"->False}] Normally Method option for Plot[] is Automatic. I don't know whether there are any side effects of changing it. John Payne