Re: can't find info about & /@ %
- To: mathgroup at smc.vnet.net
- Subject: [mg121913] Re: can't find info about & /@ %
- From: Heike Gramberg <heike.gramberg at gmail.com>
- Date: Thu, 6 Oct 2011 04:24:31 -0400 (EDT)
- Delivered-to: l-mathgroup@mail-archive0.wolfram.com
- References: <201110050759.DAA06921@smc.vnet.net>
& is shorthand for Function. It's used in Postfix notation so expr & is
the same as Function[expr]. The parameters of the function are denoted
with #1 (or #), #2, =85 etc.
/@ is short for Map. Instead of using f /@ {a, b, c} you can also write
Map[f, {a,b,c}] which returns {f[a], f[b], f[c]}.
%, or Out[], gives the last result generated (which in your case is
probably a list of images).
So in summary, your example could have been written as
First[Map[Function[Options[#, "ColorSpace"]], Out[]]]
Heike.
On 5 Oct 2011, at 09:59, Richard Cohen wrote:
> First[Options[#, "ColorSpace"] & /@ %]
> could someone please explain the use of these & /@ %
> i've looked everywhere to no avail.
> rich
>
- References:
- can't find info about & /@ %
- From: Richard Cohen <cohenrich@gmail.com>
- can't find info about & /@ %