Mathematica 9 is now available
Services & Resources / Wolfram Forums / MathGroup Archive
-----

MathGroup Archive 2013

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Position

  • To: mathgroup at smc.vnet.net
  • Subject: [mg131131] Re: Position
  • From: "Alexander Elkins" <alexander_elkins at hotmail.com>
  • Date: Fri, 14 Jun 2013 04:56:15 -0400 (EDT)
  • 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
  • References: <kpbp24$95n$1@smc.vnet.net>

Use Condition(/;) on a Pattern named x matching any Real to test x for
Greater than 2.0 like so:

In[1]:=
Position[{1.4,3.5,2.1,-1.2},x_Real/;x>2.]

Out[1]=
{{2},{3}}

In[2]:=
FullForm[x_Real /; x > 2.]

Out[2]=
Condition[Pattern[x, Blank[Real]], Greater[x, 2.`]]

Or use PatternTest on an unnamed pattern matching any Real to test it for
Greater than 2.0 like so:

In[3]:=
Position[{1.4,3.5,2.1,-1.2},_Real?(#>2.&)]

Out[3]=
{{2},{3}}

In[4]:=
FullForm[_Real?(#>2.&)]

Out[4]//FullForm=
PatternTest[Blank[Real],Function[Greater[Slot[1],2.`]]]

"Costa Bravo" <q13a27tt at aol.com> wrote in message
news:kpbp24$95n$1 at smc.vnet.net...
> How can I find the indices  of all  elements greaters than e.g. 2 of a
vector.
>
> t=RandomReal[{0,5},100]
> Position[t,??]
>
> --
>   Costa
>





  • Prev by Date: exporting tetrahedral meshes
  • Next by Date: Re: Applying data from a database link to a GraphPlot
  • Previous by thread: Re: Position
  • Next by thread: Re: Position