Wikipedia:Reference desk/Archives/Mathematics/2011 May 9

= May 9 =

Matlab number formatting
Hi, I know this is not a terribly exciting maths question, but: when I use Matlab, sometimes it spits out the numbers (if it is a matrix) using a single exponent (i.e.: x10^3) at the top, then it displays the matrix or vector as a list of numbers that the user has to multiply by this power of 10. Does anyone know how to turn off this annoying feature? Thanks, It&#39;s been emotional (talk) 19:21, 9 May 2011 (UTC)
 * "format short g" 86.147.0.56 (talk) 21:48, 9 May 2011 (UTC)

Yes, that seems to be the one. Thanks! It&#39;s been emotional (talk) 16:33, 10 May 2011 (UTC)

3D analog of a plane
In 4D geometry and higher, what's the name for the 3D analog of a point/line/plane? --75.40.204.106 (talk) 23:21, 9 May 2011 (UTC)
 * Often hyperplane, or sometimes just "3-dimensional subspace". Staecker (talk) 23:24, 9 May 2011 (UTC)
 * A hyperplane is a space with three dimensions in four dimensions. You also can have planes, lines and points with two, one and zero dimensions within four dimensions. Four-dimensional space has some detail but doesn't that I can see classify them.-- JohnBlackburne wordsdeeds 23:26, 9 May 2011 (UTC)

3D surface
In 4D geometry, what's the 3D version of a surface (not necessarily a plane)? --75.40.204.106 (talk) 23:32, 9 May 2011 (UTC)
 * A hypersurface.-- JohnBlackburne wordsdeeds 23:35, 9 May 2011 (UTC)