       Re: Part Function

• To: mathgroup at smc.vnet.net
• Subject: [mg132256] Re: Part Function
• From: Bob Hanlon <hanlonr357 at gmail.com>
• Date: Fri, 24 Jan 2014 04:20:38 -0500 (EST)
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```Q1[k, 1] doesn't return anything useful since Q1 is not a function and
[k,1] is the form of an argument to a function.

For a part, you should be using Q1[[k,1]] rather than Q1[k,1].

Q1 = Array[q, {96, 96}];

With[{
k = RandomInteger[{1, 96}],
n = RandomInteger[{1, 96}]},
Part[Q1[[k]], n] === Q1[[k]][[n]] === Q1[[k, n]]
]

True

See documentation for Part.

Bob Hanlon

On Thu, Jan 23, 2014 at 3:34 AM, Fred Najmy <fnajmy at gmail.com> wrote:

> 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.
>
>

```

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