Develop Reference

Determining if text is english

I currently have a lot comments and text in my database that is mainly in English. However if it isn't in English I want to translate it to English.
I know I can call a translation api to determine the language but I don't want to make millions of translation API calls for text that most likely won't need translating.
I am looking for a way to determine if the text is English or not. I don't need to know what language it is, just that it isn't English, then if it isn't English I will send it to a translation service API.

The Chromium project (including its most popular implementation, Google Chrome) solves this problem with https://github.com/google/cld3.
If your only need is to detect whether or not something is English, then in theory you can use something even more compact.
Most good language detectors use trigram frequency (a gram being a single character) or trigram frequency overlaid with word frequency. For your application it seems that you could use a hybrid approach where the first pass is local, but of low accuracy and tuned to be a bit aggressive to not miss any potential English, and the second pass that does hit an API like Google Translate.
The popularity of English and amount of English data is usually helpful for applying NLP solutions to it, but in this case unfortunately you will often find false positives for English, because sources of data that are listed as English contain other languages or un-language like garbage characters or URLs.
Note also that for many queries there is no single correct answer. Good systems will return a weighted list of possibilities, but for a query like [dan], [a], [example#example.com] or [hi! como estas? i'm in class ahorita] the most correct answer will depend on your application and may not exist.

You can use NTextCat to determine input language.

Research (by a certian Zipf) determined that for the most part, there are some words which are used very frequently, and a lot of words which are rarely used.
If I was given this problem, I'd probably put down a list of the top X used words. Then for each comment I would see if there's a match.
It's not perfect (and if the text is very particular, or mispelt, you've got an issue) - but I think it's an acceptable heuristic.

See this post
More specifically, take a look on Trigrams

Spell Check Feature in C# Windows Form Application [duplicate]

I'd like to give users the ability to search through a large list of businesses, but still find near matches.
Does anyone have any recommendations on how best to go about this when you're not targeting simple dictionary words, but instead complex names like ABC Business Name?
Regards.

Check out the wikipedia article on Levenshtein distance. It's a fairly simple concept to wrap your head around and pretty easy to implement an algorithm in whichever language you are using, in your case, C#.
I found an example in C# for you here.
Also, here is an example of a spelling corrector from Peter Norvig of Google. It was said on the SO podcast a few episodes ago that Jon Skeet attempted a rewrite of this same algorithm in C#. Not sure if he completed it and/or made it publicly available though.

Consider using Keyword match and edit distance based similarity. Might combine with 'original searched' to 'actually clicked'.

This is probably a crazy solution but could you split the business name by space and then search either all the items or maybe the first couple.
So you might search on 'ABC' and 'Business' but leave out 'Name' as this might take too long.
You might even check to see if the string is of a certain length, then trim and just search on the first say 5 letters.
Have you had a look at "soundex" as a way of searching through your businesses. Again, I think you'd need to split the name by space.

You might check out the SQL Server SOUNDEX and DIFFERENCE functions. SOUNDEX converts a sequence of characters (such as a word) into a 4-character code which will be the same for similar-sounding words. DIFFERENCE gives a number which represents how "different" two strings are based on sound.
You could, for example, create a computed column based on the SOUNDEX function and match on that column later. Or you could use DIFFERENCE in a WHERE clause.

Is there any way to convert English verbs to it's present tense on C#

I'm working on a Windows Phone application using C# and I want to know if there is a regular expression/library/helper or anything to get present tense verb (or base form verb) from an input verb
example:
lived >> live
built >> build
working >> work
so far i found a loose solution to singularize plural words.
And I think this can be modified/added some regex rules to make it work with tenses.
But i'm not good in regex (neither English linguistics)
http://lotsacode.wordpress.com/2010/03/05/singularization-pluralization-in-c
My situation is:
When user trying to find some word that is not in database it will suggest something
such like typed "dragons" it will give result for "dragon"

The solution may need to be more sophisticated than you think. Any effective approach will need to include some kind of dictionary, because there are so many irregular verbs in the English language. The difficulty is illustrated well by considering the word "saw". Is it a noun? Is it a verb? Is it the present tense of the verb "to saw"? Is it the past tense of the verb "to see"? This can only be inferred from context.
In short, it's not simple text processing. There must be logic that can apply contextual processing of English phrases.

I think you should try using SharpNLP, not used it, but sure it would help you in some way also see this Article.

Regex for Words or Names For a Specific Language

I'm interested in language-specific validators via regex. I know that I can validate a person's name, in any language, with a pattern like this:
“[\p{L}\p{M}]”
But what if I want validation to be for a specific language? It would be nice if my thread's CurrentUICulture or CurrentCulture setting would simply convert the meaning of "[\w]" to something appropriate for German, Spanish, English, and especially Chinese. Does it work that way? If yes, then this is likely my answer.
If not, then my next interest would be to use a regex script annotation. However, I notice that:
The list given in that link does not include simplified "Chinese", which I am particularly interested in.
I don't think .NET regex capabilities support script-based matching. Yes? No?
So my final option, if I can't get the prior two options to work, is to turn to named blocks. At least the list of .net supported named blocks includes several entries for CJK. I suppose I can simply combine the several CJK blocks, and call that (simplified) "Chinese."
Thoughts?

I have concluded that, in a .net setting, there is no such thing as a regex that is sensitive to the CurrentUICulture. I have also concluded that the most permissive reasonable scenario is to perform a validation - applicable to all languages simultaneously - that simply rejects all forms of non-printable characters, "dingbats", angle-brackets (to prevent markup injection), and math symbols:
#”^[^\p{C}<>\p{Sm}\p{So}]*$”
The mid-permissive approach is to use a string that expressly captures both Western and Eastern character sets (including diacritics and "combining characters"):
#"^[\p{L}\p{M}\p{Pd}\p{Pi}\p{Pf}\s]*$"
The least-permissive approach, if I want only Western characters, is this:
#"^[\p{IsBasicLatin}\p{IsLatin-1Supplement}\p{Pd}\p{Pi}\p{Pf}-[\p{N}]]*$"
The above still allows all forms of quote marks, which usually apply for names like O'Toole.

Should you use international identifiers in Java/C#?

C# and Java allow almost any character in class names, method names, local variables, etc.. Is it bad practice to use non-ASCII characters, testing the boundaries of poor editors and analysis tools and making it difficult for some people to read, or is American arrogance the only argument against?

I would stick to english, simply because you usually never know who is working on that code, and because some third-party tools used in the build/testing/bugtracking progress may have problems. Typing äöüß on a Non-German Keyboard is simply a PITA, and I simply believe that anyone involved in software development should speak english, but maybe that's just my arrogance as a non-native-english speaker.
What you call "American arrogance" is not whether or not your program uses international variable names, it's when your program thinks "Währung" and "Wahrung" are the same words.

I'd say it entirely depends on who's working on the codebase.
If you have a small group of developers who all share a common language and you don't ever plan needing anyone who doesn't speak the language to work on the code then go ahead and use whatever characters you want.
If you need to have people of varying cultures and languages working on the code then it's probably best to stick with English since it's the common denominator for just about everyone in the world.

If your business are non-English speakers, and you think Domain Driven Design has something to it, then there is another aspect: How do we, as developers, use the same domain language as our business without any translation overhead?
That does not only mean translations between languages, say English and Norwegian, but also between different words. We should use the exact same words as our business for our entity classes and services.
I have found it easier to just give in and use my native language. Now that my code use the same words, it's easier to have a conversation with my domain experts. And after a while you get used to it, just like how you got used to code without Hungarian notation.

I used to work in a development team that happily wiped their asses with any naming (and for that matter any other coding) conventions. Believe it or not, having to cope with ä's and ö's in the code was a contributing factor of me resigning. Though I'm Finnish, I prefer writing code with US keyboard settings because curly and square brackets are a pain to write in a Finnish keyboard (try right alt and 7 and 0 for curlies).
So I say stick with the ascii characters.

Here's an example of where I've used non-ASCII identifiers, because I found it more readable than replacing the greek letters with their English names. Even though I don't have θ or φ on my keyboard (I relied on copy-and-paste.)
However these are all local variables. I would keep non-ASCII identifiers out of public interfaces.

It depends:
Does your team conform to any existing standards that require your using ASCII?
Is your code ever going to be feasibly reused or read by someone who doesn't speak your native language?
Do you envision a scenario where you'll need to ask for help online and will therefore not be able to copy-paste your code sample in as-is?
Are you certain your entire suite of tools support code encoding?
If you answered 'yes' to any of the above, stay ASCII only. If not, go forward at your own risk.

Part of the problem is that the Java/C# language and its libraries are based on English words like if and toString(). I personally would not like to switch between non-English language and English while reading code.
However, if your database, UI, business logics (including metaphors) are already in some non-English language, there's no need to translate every method names and variables into English.

IF you get past the other prerequisites you then have one extra (IMHO more important) one - How difficult is the symbol to type.
On my regular en-us keyboard, the only way I know of to type the letter ç is to hold alt, and hit 0227 on the numeric keypad, or copy and paste.
This would be a HUGE big roadblock in the way of typing quickly. You don't want to slow your coding down with trivial stuff like this if you aren't forced to. International keyboards may alleviate this, but then what happens if you have to code on your laptop which doesn't have an international keyboard, etc?

I would stick to ASCII characters because if anyone in your development team is using an SDK that only supports ASCII or you wanted to make your code open source, alot of problems could arise. Personally, I would not do it even if you are not planning on bringing anyone who doesn't speak the language in on the project, because you are running a business and it seems to me that one running a business would want his business to expand, which in this day and age means transcending national borders. My opinion is that English is the language of the realm, and even if you name your variables in a different language, there is little to no point to use any non-ASCII characters in your programming. Leave it up to the language to deal with it if you are handling data that is UTF8: my iPhone program (which involves tons of user data going in between the phone and server) has full UTF8 support, but has no UTF8 in the source code. It just seems to open such a large can of worms for almost no benefit.

There is another hazzard to using non-ASCII characters, though it will probably only bite in obscure cases. The allowed characters are defined in terms of the methods Character.isJavaIdentifierStart(int) and Character.isJavaIdentifierPart(int), which are defined in terms of Unicode. However, the exact version of Unicode used depends on the version Java platform, as specified in the documentation for java.lang.Character.
Since character properties change slightly from one Unicode version to the next, it's possible (but probably very unlikely) you could have identifiers that are valid in one version of Java, but not in the next.

As already pointed out, unless method names mostly match the language, it is a bit weird to constantly switch languages while reading.
For the Scandinavian languages & German, which I can speak and thus speak for, I would at least recommend using standard substitutions, ie.
ä/æ -> ae, ö/ø -> oe, å -> aa, ü -> ue
etc. just in case as others may find it difficult to type the original letters without keyboard/keymap changes. Think if you suddenly had to work with a codebase where the developers used a third language (for instance including the French ç) and didn't do this.. Switching between more than 2 keymaps to type efficiently would be painful in my experience.