Mathematica 9 is now available
Services & Resources / Wolfram Forums
-----
 /
MathGroup Archive
1995
*January
*February
*March
*April
*May
*June
*July
*August
*September
*October
*November
*December
*Archive Index
*Ask about this page
*Print this page
*Give us feedback
*Sign up for the Wolfram Insider

MathGroup Archive 1995

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

Search the Archive

Re: extract elements from a list

  • To: mathgroup at smc.vnet.net
  • Subject: [mg2862] Re: extract elements from a list
  • From: "Stuart C. Schaffner" <sch at mitre.org>
  • Date: Sat, 30 Dec 1995 01:01:33 -0500
  • Organization: The MITRE Corp.

Dave Wagner has already ably answered part of your query, but I thought
I would add a few comments.

Yes, you can stick to the FORTRAN subset of Mathematica, but it is
often easier to make at least limited use of the other features of
the language.

Reformulate your problem, as follows:

Let x be a list of real numbers. We need a list y that is the same
size as x, but where if element i of x is a then the corresponding
element of y should be Line[ { { 5, 25 }, { a, a^2 } } ].
Mathematically, this is a mapping. Then Show[ Graphics[ y ] ].

The following should do this:

x = { 5, 5.5, 5.4, 5.3 };
makeLine[ x_ ] := Line[ { { 5, 25 }, { x, x^2 } } ];
y = Map[ makeLine, x ];
Show[ Graphics[ y ] ];

If you like one-liners, this also works:

Show[ Graphics[ Line[ { { 5, 25 }, { #, #^2 } } ]& /@ x ] ]

Here I have used the & operator to make an inline function
declaration and have used the /@ abbreviation for the Map
function.

Good luck and keep trying.





  • Prev by Date: Mathematica vs ?
  • Next by Date: Mathematica vs ?
  • Previous by thread: Re: extract elements from a list
  • Next by thread: Re: extract elements from a list