I am trying to identify an extended ascii charset where 0xE1 is an "a" with an umlaut (8859-1 character E4)
and 0xF5 is a "u" with an umlaut (8859-1 character FC).
Has anyone seen this charset before? It quite possibly dates back to the 80's.
To my knowledge, there are no standard ASCII character sets which use those symbols. Here is a list of the standard character sets: http://www.columbia.edu/kermit/csettables.html
However, the character set you referenced is in fact used for interfacing with some LEDs, for example HT1632-compliant LEDs use the same character set: http://blog.thiseldo.co.uk/wp-filez/USB_HT1632_Matrix.pde
I hope this helps.
These are in the commonly used ISO-8859-1 character set, also known as latin-1.
Related
I'm receiving a string from the server and it has the special characters in code. Here's the example:
"El usuario o las contrase\UOOOOfffda no son v\UOOOOfffdlidos"
The first one should be an "ñ" and the second one "á"
I know it's not complicated but I can't find the answer. How can I get the string with the special characters correctly formatted?
Unicode U+FFFD (in your string, displayed as UTF-32 \U0000fffd) is "�", the replacement character. It is often substituted in strings when a system encounters unrecognized characters.
This character really shouldn't appear in string data since its purpose is to indicate an error in displaying or interpreting the string. Since your server is sending you that character for both ñ and á, there is no way to retrieve the correct character.
How are you "receiving" this string? It could be that you are accessing the server incorrectly so it isn't sending you an unmodified string.
Unicode for those characters should look like this:
#"accented-a is \u00f1, and tilda-n is \u00e1"
But it's not clear what you're getting from the server makes any sense. The objective-c literal must have a lowercase leading "u" followed only by valid hex digits (0-9 and a-f). I don't see a transformation that changes the literals you have to the ones you expect.
Once the characters are formatted properly, the built-in classes will just work, for example, assigning the string to a label's text property will show the user a nice glyph.
I am now working with an iOS app that handle unicode characters, but it seems there is some problem with translating unicode hex value (and int value too) to character.
For example, I want to get character 'đ' which has Unicode value of c491, but after this code:
NSString *str = [NSString stringWithUTF8String:"\uc491"];
The value of str is not 'đ' but '쓉' (a Korean word) instead.
I also used:
int c = 50321; // 50321 is int value of 'đ'
NSString *str = [NSString stringWithCharacters: (unichar *)&c length:1];
But the results of two above pieces of code are the same.
I can't understand what is problem here, please help!
The short answer
To specify đ, you can specify it in the following ways (untested):
#"đ"
#"\u0111"
#"\U00000111"
[NSString stringWithUTF8String: "\u0111"]
[NSString stringWithUTF8String: "\xc4\x91"]
Note that the last 2 lines uses C string literal instead of Objective-C string object literal construct #"...".
As a short explanation, \u0111 is the Unicode escape sequence for đ, where U+0111 is the code point for the character đ.
The last example shows how you would specify the UTF-8 encoding of đ (which is c4 91) in a C string literal, then convert the bytes in UTF-8 encoding into proper characters.
The examples above are adapted from this answer and this blog post. The blog also covers the tricky situation with characters beyond Basic Multilingual Plane (Plane 0) in Unicode.
Unicode escape sequences (Universal character names in C99)
According to this blog1:
Unicode escape sequences were added to the C language in the TC2 amendment to C99, and to the Objective-C language (for NSString literals) with Mac OS X 10.5.
Page 65 of C99 TC2 draft shows that \unnnn or \Unnnnnnnn where nnnn or nnnnnnnn are "short-identifier as defined by ISO/IEC 10646 standard", it roughly means hexadecimal code point. Note that:
A universal character name shall not specify a character whose short identifier is less than 00A0 other than 0024 ($), 0040 (#), or 0060 (`), nor one in the range D800 through DFFF inclusive.
Character set vs. Character encoding
It seems that you are confused between code point U+0111 and UTF-8 encoding c4 91 (representation of the character as byte). UTF-8 encoding is one of the encoding for Unicode character set, and code point is a number assigned to a character in a character set. This Wikipedia article explains quite clearly the difference in meaning.
A coded character set (CCS) specifies how to represent a repertoire of characters using a number of (typically non-negative) integer values called code points. [...]
A character encoding form (CEF) specifies the conversion of a coded character set's integer codes into a set of limited-size integer code values that facilitate storage in a system that represents numbers in binary form using a fixed number of bits [...]
There are other encoding, such as UTF-16 and UTF-32, which may give different byte representation of the character on disk, but since UTF-8, UTF-16 and UTF-32 are all encoding for Unicode character set, the code point for the same character is the same between all 3 encoding.
Footnote
1: I think the blog is correct, but if anyone can find official documentation from Apple on this point, it would be better.
I have several small place marks such as 'א,א' 'א,ב'. If we use the comma as the center point, i need at most 2 characters before the comma, and up to the next space after the comma.
I have (.-,.-)%s but its not doing what I need. Any idea?
Also as you can see there not latin letters so using %l will not work.
There are couple of issues here. First, a minor issue: .-, will match as little as possible before the coma, that is zero characters. You should anchor the beginning of the matched string.
The more complicated issue is that you use Hebrew letters. The problem is that Lua has no concept of multi-byte characters.
If you use a 8-bit encoding such as Windows-1255, or ISO-8859-8, then you probably can simply match against a character class [ת-א]. If you have properly set Hebrew locale, %l should work fine for you.
If you use UTF-8 or any other encoding that uses multi-byte characters, then you must construct a regex that has all the Hebrew alphabet escaped as a sequence of octets. The aleph is U+05D0x, which in UTF-8 will be represented as 0xD7 0x90. The tav is U+05EA, which will be encoded as 0xD7 0xAA.
In Lua you can escape any 8-bit character with a backslash + decimal code. All the hebrew characters encoded in UTF-8 have the first byte the same -- 0xD7, that is "\215". The second character can be anything from "\144" to "\170". Thus, the regex that will match a single Hebrew letter is: "\215[\144-\170]". Put that in your original regex, where you had single dots that match any character.
Of course, the above reasoning must be modified for encodings different than UTF-8. Right-to-left writing direction in Hebrew is another thing to keep in mind.
I'm trying to process a German word list and can't figure out what encoding the file is in. The 'file' unix command says the file is "Non-ISO extended-ASCII text". Most of the words are in ascii, but here are the exceptions:
ANDR\x82
ATTACH\x82
C\x82ZANNE
CH\x83TEAU
CONF\x82RENCIER
FABERG\x82
L\x82VI-STRAUSS
RH\x93NETAL
P\xF2ANGE
Any hints would be great. Thanks!
EDIT: To be clear, the hex codes above are C hex string literals so replace \xXX with the literal hex value XX.
It looks like CP437 or CP852, assuming the \x82 sequences encode single characters, and are not literally four characters. Well, at least everything else does, but the last line is a bit of a puzzle.
I've parsed an HTML page with mochiweb_html and want to parse the following text fragment
0 – 1
Basically I want to split the string on the spaces and dash character and extract the numbers in the first characters.
Now the string above is represented as the following Erlang list
[48,32,226,128,147,32,49]
I'm trying to split it using the following regex:
{ok, P}=re:compile("\\xD2\\x80\\x93"), %% characters 226, 128, 147
re:split([48,32,226,128,147,32,49], P, [{return, list}])
But this doesn't work; it seems the \xD2 character is the problem [if I remove it from the regex, the split occurs]
Could someone possibly explain
what I'm doing wrong here ?
why the '–' character seemingly requires three integers for representation [226, 128, 147]
Thanks.
226,128,147 is E2,80,93 in hex.
> {ok, P} = re:compile("\xE2\x80\x93").
...
> re:split([48,32,226,128,147,32,49], P, [{return, list}]).
["0 "," 1"]
As to your second question, about why a dash takes 3 bytes to encode, it's because the dash in your input isn't an ASCII hyphen (hex 2D), but is a Unicode en-dash (hex 2013). Your code is recieving this in UTF-8 encoding, rather than the more obvious UCS-2 encoding. Hex 2013 comes out to hex E28093 in UTF-8 encoding.
If your next question is "why UTF-8", it's because it's far easier to retrofit an old system using 8-bit characters and null-terminated C style strings to use Unicode via UTF-8 than to widen everything to UCS-2 or UCS-4. UTF-8 remains compatible with ASCII and C strings, so the conversion can be done piecemeal over the course of years, or decades if need be. Wide characters require a "Big Bang" one-time conversion effort, where everything has to move to the new system at once. UTF-8 is therefore far more popular on systems with legacies dating back to before the early 90s, when Unicode was created.