Re: Plotting a straight line in a 3D plot

*To*: mathgroup at smc.vnet.net*Subject*: [mg81050] Re: Plotting a straight line in a 3D plot*From*: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>*Date*: Sun, 9 Sep 2007 06:15:56 -0400 (EDT)*Organization*: The Open University, Milton Keynes, UK*References*: <fbqq6f$727$1@smc.vnet.net>

kheimon wrote: > Is there any way, in Mathematica, I can plot a straight line in a 3D > plot environment? > > For example: Plot3D[{{y = 1 - x, z = y - 1}}, {x, -5, 5}, {y, -5, 5}] > > plots two surfaces, not their intersection (which is a straight line). First, the given example will work better if written as follows (the assignments = have been removed as well as the extra curly brackets), Plot3D[{1 - x, y - 1}, {x, -5, 5}, {y, -5, 5}] Second, to plot a line in 3D, one can use *Graphics3D* and *Line* as in Graphics3D[Line[{{0, 0, 0}, {1, 1, 1}}]] and one can combine a regular plot with a line with *Show* Show[Plot3D[{1 - x, y - 1}, {x, -5, 5}, {y, -5, 5}], Graphics3D[Line[{{0, 0, 0}, {0, 5, 5}}]]] HTH, -- Jean-Marc