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August 7

PCIe WiFi adapter with full 5Ghz 802.11ac support under Linux.

Subject says it all. Which ones fit this requirement? 100.2.252.204 (talk) 00:18, 7 August 2016 (UTC)[reply]

We apparently have a big list of FLOSS wireless drivers. This is the more "official" list for Linux. It helps to know what chip a given adapter uses. Sometimes this is listed in the product information, but if not, a Web search for "<name of adapter> linux" often will give you some information. --71.110.8.102 (talk) 23:00, 7 August 2016 (UTC)[reply]

Why is a = 2*b wrong?

In Python, a = 2*b is wrong.

If I have not assigned a value to 'b' yet, but already know that 'b' is half as big as 'a', shouldn't a language like Python allow for expressing this relationship? At some later point, the 'b' would have a value assigned to it, and therefore, 'a' would have gotten also a value. Llaanngg (talk) 13:19, 7 August 2016 (UTC)[reply]

No, Python is eager. Your reasoning might well hold in a language that is lazy. -- Finlay McWalter··–·Talk 14:37, 7 August 2016 (UTC)[reply]

Our article is mostly about other related meanings, but note that you can use delayed evaluation in many languages, although you have to request it explicitly (presumably because of the increased cost). In Python, it would look like

def a(): return 2*b
# b=...
# ... and use "a()" instead of "a" forever after

In Wolfram Language (i.e., Mathematica), which is one of very few languages where ordinary variable lookup can be delayed:

a:=2*b      (* the colon delays evaluation of the RHS *)
(* b=... *) (* optional! *)
(* use plain "a" *)

However, in that language the distinction is not very important in simple cases of arithmetic because b may be used symbolically before it has a value anyway. --Tardis (talk) 16:19, 7 August 2016 (UTC)[reply]