Re: Preventing unwanted threading by Inner
- To: mathgroup at smc.vnet.net
- Subject: [mg123559] Re: Preventing unwanted threading by Inner
- From: DrMajorBob <btreat1 at austin.rr.com>
- Date: Sun, 11 Dec 2011 03:47:12 -0500 (EST)
- Delivered-to: l-mathgroup@mail-archive0.wolfram.com
- References: <jbni23$47f$1@smc.vnet.net> <jbq49t$itm$1@smc.vnet.net>
- Reply-to: drmajorbob at yahoo.com
I think Chris meant: Sum[(HoldForm[#1^2] & )[i], {i, 1, 10}] 1^2+2^2+3^2+4^2+5^2+6^2+7^2+8^2+9^2+10^2 or (I converted the first cell to InputForm in Mathematica, copied the output as Plain Text, and pasted both into e-mail.) Bobby On Sat, 10 Dec 2011 06:31:49 -0600, Chris Young <cy56 at comcast.net> wrote: > On 2011-12-08 10:42:05 +0000, Ray Koopman said: > >> This is a little better than my first suggestion. >> >> Inner[Times, {a1,a2,a3}, HoldForm /@ >> {{b11,b12},{b21,b22},{b31,b32}}, Plus] >> >> a1 {b11,b12} + a2 {b21,b22} + a3 {b31,b32} > > I see in the Help that HoldForm can help with preventing unwanted > expansion of a lot of formulas: > > Display a sum of squares in unevaluated form: > > \!\( > \*UnderoverscriptBox[\(\[Sum]\), \(i = 1\), \(10\)]\(\((HoldForm[ > \*SuperscriptBox[\(#1\), \(2\)]] &)\)[i]\)\) > > \!\(\* > TagBox[ > SuperscriptBox["1", "2"], > HoldForm]\) + \!\(\* > TagBox[ > SuperscriptBox["2", "2"], > HoldForm]\) + \!\(\* > TagBox[ > SuperscriptBox["3", "2"], > HoldForm]\) + \!\(\* > TagBox[ > SuperscriptBox["4", "2"], > HoldForm]\) + \!\(\* > TagBox[ > SuperscriptBox["5", "2"], > HoldForm]\) + \!\(\* > TagBox[ > SuperscriptBox["6", "2"], > HoldForm]\) + \!\(\* > TagBox[ > SuperscriptBox["7", "2"], > HoldForm]\) + \!\(\* > TagBox[ > SuperscriptBox["8", "2"], > HoldForm]\) + \!\(\* > TagBox[ > SuperscriptBox["9", "2"], > HoldForm]\) + \!\(\* > TagBox[ > SuperscriptBox["10", "2"], > HoldForm]\) > > -- DrMajorBob at yahoo.com