Re: Part Function

*To*: mathgroup at smc.vnet.net*Subject*: [mg132259] Re: Part Function*From*: Alexei Boulbitch <Alexei.Boulbitch at iee.lu>*Date*: Fri, 24 Jan 2014 04:21:38 -0500 (EST)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*Delivered-to*: l-mathgroup@wolfram.com*Delivered-to*: mathgroup-outx@smc.vnet.net*Delivered-to*: mathgroup-newsendx@smc.vnet.net

I have a Mathematica script containing the following line: v[k_] := SetAccuracy(2*(Part[Q1[[k]],1]),45] where Q1 is a 96 x 96 matrix. Is Part[Q1[[k]],1] the same as Q1[k,1]? If not, what is it returning? Any help appreciated. Hi, Fred, It is easy to see what is it by generating a simple example. Let us define a small matrix as follows: Q[k_] := {{k + 1, k - 1}, {k^2, 1/k}} You can have a look at it. Evaluate this: Q[k] // MatrixForm. Now the expression you are asking about is: Part[Q[k], 1] Evaluate it! The result is below: {1 + k, -1 + k} Thus, it returns the first line of the matrix. Have fun, Alexei Alexei BOULBITCH, Dr., habil. IEE S.A. ZAE Weiergewan, 11, rue Edmond Reuter, L-5326 Contern, LUXEMBOURG Office phone : +352-2454-2566 Office fax: +352-2454-3566 mobile phone: +49 151 52 40 66 44 e-mail: alexei.boulbitch at iee.lu