Re: What's going on here (Table-generated lists)?

*To*: mathgroup at smc.vnet.net*Subject*: [mg97976] Re: [mg97956] What's going on here (Table-generated lists)?*From*: Bob Hanlon <hanlonr at cox.net>*Date*: Fri, 27 Mar 2009 05:33:16 -0500 (EST)*Reply-to*: hanlonr at cox.net

Attributes[Plot] {HoldAll,Protected} Note the HoldAll Plot[Evaluate[Table[k x, {k, 1, 5}]], {x, -1, 1}] Bob Hanlon ---- Erik Max Francis <max at alcyone.com> wrote: ============= I'm seeing a difference in behavior with Plot in conjunction with Table, and I'm rather confused at the reason. If I use Plot to plot a list of functions, it works as expected, and I get a plot with each function in its own color: Plot[{x, 2 x, 3 x, 4 x, 5 x}, {x, -1, 1}] If I use Table, then this doesn't work the same way -- the five lines are all plotted with the same color: Plot[Table[k x, {k, 1, 5}], {x, -1, 1}] I verified that the both objects created have a Head of List, so I don't see anything obviously different about them. Here's what confuses me more: If I generate the table separately and then use that as a result in a later evaluation in the Plot, then I get the colors back: In[25]:= Table[k x, {k, 1, 5}] Out[25]= {x, 2 x, 3 x, 4 x, 5 x} In[26]:= Plot[%, {x, -1, 1}] What is going on here? Is it something like Plot does a special scan of its first argument before Evaluating it, and if it doesn't start out as a List, it concludes that it's all one thing and plots it with the same color, as opposed to an explicitly provided list of separate colors? -- Erik Max Francis && max at alcyone.com && http://www.alcyone.com/max/ San Jose, CA, USA && 37 18 N 121 57 W && AIM, Y!M erikmaxfrancis In this world, nothing is certain but death and taxes. -- Benjamin Franklin