Additive inverses of lists?

*To*: mathgroup at smc.vnet.net*Subject*: [mg95747] Additive inverses of lists?*From*: Erik Max Francis <max at alcyone.com>*Date*: Mon, 26 Jan 2009 05:01:27 -0500 (EST)

Is this a known no-no, or did I find something new? (I obviously originally tried it in the graphical front end; I'm only doing it from the command line interface for demonstration.) max@boron:~% math Mathematica 7.0 for Linux x86 (32-bit) Copyright 1988-2008 Wolfram Research, Inc. In[1]:= StreamPlot[-{x, y}, {x, -3, 3}, {y, -3, 3}] zsh: segmentation fault math Interestingly enough if the StreamPlot is not involved, nothing but happens: In[1]:= -{a, b} Out[1]= {-a, -b} And plotting {-x, -y} instead of -{x, y} works fine: In[1]:= StreamPlot[{-x, -y}, {x, -3, 3}, {y, -3, 3}] Out[1]= -Graphics- -- 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 Only love is worth the risk -- Oleta Adams