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Re: Re: A Sum-like notation for iteration

• To: mathgroup at smc.vnet.net
• Subject: [mg102422] Re: [mg102415] Re: A Sum-like notation for iteration
• From: "David Park" <djmpark at comcast.net>
• Date: Sun, 9 Aug 2009 06:03:38 -0400 (EDT)
• References: <h5bk7g$hn3$1@smc.vnet.net> <h5ebii$1rc$1@smc.vnet.net> <25942001.1249723828825.JavaMail.root@n11>

One possibility is to use ellipsis notation from Presentations.

iTable[f[x], {x, 1, 3, , 99}]

{f[1],f[3],\[CenterEllipsis],f[99]}

Generalizing the second case somewhat:

iTable[f[Subscript[x, i]], {i, 1, 2, , n}, tag1]
% // iTableNormalize[tag1, {Subscript[x, i], {3, 1, 100, Sin[2]}}]

{f[Subscript[x, 1]],f[Subscript[x, 2]],\[CenterEllipsis],f[Subscript[x, n]]}

{f[3], f[1], f[100], f[Sin[2]]}

Ellipsis expressions are common mathematical notations and mathematicians
are pretty quick to spot the patterns. But they certainly aren't a universal
solution.

By the way, T-Rex had a brain both in his head, and a smaller brain in his
tail. He was thus able to reason both a priori and a posteriori.


David Park
djmpark at comcast.net
http://home.comcast.net/~djmpark/  
 


From: magma [mailto:maderri2 at gmail.com] 


Quote: how do we format something like Table[f[x], {x, 1, 100, 2}]?
Or,
worse, Table[f[x], {x, {1,2,3,4,5}}]? Whatever solution is chosen, the
point is that it is no longer "intuitive", at least not in the sense
that one could readily guess what it should look like.