Recent submissions

Comment · 6 years ago
The main difference is that engineers have a code of ethics they're expected to uphold, with the threat of taking away your certification if you don't.
Comment · 6 years ago
If you read the article, they discuss it there.
Comment · 7 years ago
And said notation causes the generic type system to be Turing complete, as in the Java case.
Comment · 7 years ago
There are only two "natural" problem classes known that are not either definitely in P or definitely in NP, and this article concerns one of them. (The other is integer factorization / discrete logs). And I'm not sure anybody believes there are any natural problems that are inherently in this in between state.
Comment · 7 years ago
In general his complaints regarding logic are incoherent. A function is not a messy weird object in mathematics; it's a possibly infinite set of ordered pairs where there are no duplicates of the first element of the ordered pair. That's it all it is, formally. Or "class" is a concept that has highly specific meaning in NBG theory—in ZFC it's not a formal distinction and so there's a transformation that must be obeyed where "x \in Class" means "{ x | x satisfies class definition}"; which due to Foundation must be the subset of some other, preexisting, class (and thus is Russell's paradox defeated). Almost all of these things exist and are present and are extremely well defined in the theory, he just doesn't like them for some reason.
Comment · 7 years ago
The C and I presume C++ standard has been very carefully avoiding the idea of a preprocessor being separate at all. The standard was very carefully worded to prevent that being necessary, because most C compilers do not have a separate preprocessor. It is only Unix heritage compilers that really have one, and even they're not consistent about it.
Comment · 8 years ago
There's a number of fisheyes that produce circular images on rectangular film (obviously, not using the entirety of the film surface).
Comment · 8 years ago
No, but it is the one name that people remember, and saves much explanation. The Rolleicord, the Mamiya C series, and the YashicaMats, one of which is my TLR, were more consumer oriented.
Comment · 8 years ago
The #2 Brownie came out in 1901 and shot 6cm x 9cm, and all of the surviving Brownies I've seen shot rectangular formats. There was the Brownie 127 which shot square, but I only learned of its existence just now; have never seen one in the wild, probably because finding 127 film is functionally impossible.
Comment · 8 years ago
Too small, slide mounts were already standardized on 24x36, and the square was never all that popular among the general photographer. The reason why the square shape in 120 was originally developed was a technical hack. Since it outputs a square, there was never any need to hold a Hasselblad vertically; just take the photo and crop it to suit. The only square consumer oriented cameras I can think of are twin-lens reflex cameras like the Rolleiflex, which are delightful but somewhat uncommon. A number of folks started trying to make use of the square format as a square format, but it was not originally, I think, intended for that purpose.

Re: too small; an 8x10, one of the smaller standard print formats for portraits, is about an 8x enlargement from a 35mm frame. With modern materials and good technique, 8x-11x is feasible, but starting to push it at the edges; I have printed 13x17s off 35mm but I would not want to push it much larger. 35mm does 4x6s, 5x7s and 8x10s perfectly reasonably, which is what it spent most of its time doing for common consumer work. It's worth noting that one of the other common consumer cameras of the 1940s was the Brownie, which output 6cmx9cm images and was routinely contact printed, producing something smaller even than a 4x6.

120 produces images that are between 1.8x (in the 645 format) or 2.5x (in most others) as large, physically, meaning that the common enlargements are only 4x-5x. If you push it, with quality equipment, you start getting into print sizes that are super clumsy to handle like 20x24. I've never printed, personally, anything larger than a 16x20. If you do your own wet processing they're also nicer to work with—35mm negatives are real small and kinda fiddly. 4x5 sheets are also delightful to work with, of course, but they require fighting the camera in the field.

Comment · 8 years ago
I damn near released a (private) message protocol without a version field a couple months ago, and I know better. Fortunately stopped myself and added it before any actual data got released.
Comment · 10 years ago
A formal language is basically just a mathematical set of acceptable strings made up of symbols in a (typically finite) alphabet; thus the smallest is probably the empty set, or if you insist on an accepting path, a set containing only the empty string.

The interesting part comes up when you want to match an infinite set of strings with an algorithm. Probably the simplest such algorithm would be "regardless of input, accept" which isn't exactly useful but would suffice.

It's dissatisfying to have an algorithm that puts weird, arbitrary restrictions on composing languages; for example it's usually the case that if you take a language L1 and a language L2 that are both acceptable to the algorithm, the concatenation (for every string in L1 and every string in L2, the concatenation of their strings is in the new language) language is usually acceptable to the algorithm.

Some commonly used languages do not have all of these properties; in particular the intersection of two context-free languages may not be a CFL, nor the complement. Deterministic context free languages are even more restrictive. You seem to need to give some things up as you move up the language hierarchy in power; in particular string homomorphism and intersection seem to be mutually exclusive in languages more powerful than regular expressions.

If you're interested, the theory of abstract families of languages has been studied, although I do not know a lot about it myself.

Comment · 10 years ago
Comment · 10 years ago
The printing is the fun part, anyway.
Comment · 10 years ago
I love my X-Pro, and I loved Fuji film before it, but remember Fuji has never been under the anti-trust concerns Kodak has, and that forced them to divest the film processing and professional camera arms.

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