I found a dictionary of Chinese characters in unicode. I'm trying to build a database of Characters out of this dictionary but I don't know how to convert unicode to a character..
p "国".unpack("U*").first #this gives the unicode 22269
How can convert 22269 back into the character value which would be the opposite of the line above.
Ruby 1.9 :
p "国".codepoints.first #=> 22269
p 22269.chr('UTF-8') #=> "国"
[22269].pack('U*') #=> "国" or "\345\233\275"
Edit: Works in 1.8.6+ (verified in 1.8.6, 1.8.7, and 1.9.2). In 1.8.x you get a three-byte string representing the single Unicode character, but using puts on that causes the correct Chinese character to appear in the terminal.
Related
In Ruby how can I get:
"b\x81rger" by providing the string "bürger".
I need to print special characters to a Zebra printer, I can see that "b\x81rger" prints "bürger", but sending "bürger" does not print the correct character.
Turns out it’s CP850.
Proper solution (Ruby 2.5+)
Normalize the unicode string and then encode it into CP850:
"bürger".unicode_normalize(:nfc).encode(Encoding::CP850)
#⇒ "b\x81rger"
Works for both special characters and combined diacritics.
Fallback solution (Ruby 2.5-)
Encode and pray it’s a composed umlaut:
"bürger".encode(Encoding::CP850)
#⇒ "b\x81rger"
How to keep all characters converting from UTF-8 to CP1252 on ruby 2.2
this code:
file = 'd:/1 descrição.txt'
puts file.encode('cp1252')
Give this error:
`encode': U+0327 to WINDOWS-1252 in conversion from UTF-8 to WINDOWS-1252 (Encoding::UndefinedConversionError)
My application need to be cp1252, but I can't find any way to keep all the characters.
I can't replace this characters, because later I will use this info to read the file from file system.
puts file.encode('cp1252', undef: :replace, replace: '')
> d:/1 descricao.txt
ps: It is a ruby script not a ruby on rails application
UTF-8 covers the entire range of unicode, but CP1252 only includes a subset of them. Obviously this means that there are characters that can be encoded in UTF-8 but not in CP1252. This is the problem you are facing.
In your example it looks like the string only contains characters that should work in CP1252, but clearly it doesn’t.
The character in the error message, U+0327 is a combining character, and is not representable in CP1252. It combines with the preceding c to produce ç. ç can also be represented as a single character (U+00E7), which is representable in CP1252.
One option might be normalisation, which will convert the string into a form that is representable in CP1252.
file = 'd:/1 descrição.txt'.unicode_normalize(:nfc)
puts file.encode('cp1252')
(It appears that Stack Overflow is normalizing the string when displaying your question, which is probably why copying the code from the question and running it doesn’t produce any errors.)
This will avoid the error, but note that it is not necessarily possible to reverse the process to get the original string unless the original is in a known normalized form already.
str = "é-du-Marché"
I get the first char via
str.split(//).first
How I can get the rest of the string regardless of my ruby version ?
String does not have a method first. So you need in addition a split. When you do the split in unicode-mode (exactly utf-8) you have acces to the first (and other characters).
My solution:
puts RUBY_VERSION
str = "é-du-Marché"
p str.split(//u, 2)
Test with ruby 1.9.2:
1.9.2
["\u00E9", "-du-March\u00E9"]
Test with ruby 1.8.6:
1.8.6
["\303\251", "-du-March\303\251"]
With first and last you get your results:
str.split(//u, 2).first is the first character
str.split(//u, 2).last is the string after the first character.
str[1..-1] should return you everything after the first digit normally.
The first number is the starting index, which is set to 1 to skip the first digit, the second is the length, which is set to -1, so ruby counts from the back
Note: that multibyte characters only work in Ruby 1.9. If you wish to mimic this behavior downwards, you'll have to loop over the bytes yourself and figure out what needs to be removed from the data, cause Ruby 1.8 does not support this.
UPDATE:
You could try this as well, but I can't guarantee that it will work for every multibyte char:
str = "é-du-Marché"
substring = str.mb_chars[1..-1]
the mb_chars is a proxy class that directs the call to the appropiate implementation when dealing with UTF-8, UTF-32 or UTF-16 encoding of characters (e.g. multibyte chars).
More detailed info can be found here : http://api.rubyonrails.org/classes/ActiveSupport/Multibyte/Chars.html
But I do not know if this exists in older rails versions
UPDATE2:
Ruby 1.8 treats any string just as a bunch of bytes, calling size() on it will return the amount of bytes that is used to store the data. To determine the characters regardless of the encoding try this:
char_array = str.scan(/./m)
substring = char_array[1..-1].join
This should do the trick normally. Try looking at http://blog.grayproductions.net/articles/bytes_and_characters_in_ruby_18 who explains how to treat multibyte data in older ruby versions.
EDIT3:
Playing around with the scan & join operations brings me closer to your problem & solution. I honestly don't have the time at to get the full solution working but if you play with the scan(/./mu) options you convert it to utf-8, which is supported by all ruby versions.
I'm running Ruby 1.9.2 and trying to fix some broken UTF-8 text input where the text is literally "\\354\\203\\201\\355\\221\\234\\353\\252\\205" and change it into its correct Korean "상표명"
However after searching for a while and trying a few methods I still get out gibberish.
It's confusing as the escaped characters example on line 3 works fine
# encoding: utf-8
puts "상표명" # Target string
# Output: "상표명"
puts "\354\203\201\355\221\234\353\252\205" # Works with escaped characters like this
# Output: "상표명"
# Real input is a string
input = "\\354\\203\\201\\355\\221\\234\\353\\252\\205"
# After some manipulation got it into an array of numbers
puts [354, 203,201,355,221,234,353,252,205].pack('U*').force_encoding('UTF-8')
# Output: ŢËÉţÝêšüÍ (gibberish)
I'm sure this must have been answered somewhere but I haven't managed to find it.
This is what you want to do to get your UTF-8 Korean text:
s = "\\354\\203\\201\\355\\221\\234\\353\\252\\205"
k = s.scan(/\d+/).map { |n| n.to_i(8) }.pack("C*").force_encoding('utf-8')
# "상표명"
And this is how it works:
The input string is nice and regular so we can use scan to pull out the individual number.
Then a map with to_i(8) to convert the octal values (as noted by Henning Makholm) to integers.
Now we need to convert our list of integers to bytes so we pack('C*') to get a byte string. This string will have the BINARY encoding (AKA ASCII-8BIT).
We happen to know that the bytes really do represent UTF-8 so we can force the issue with force_encoding('utf-8').
The main thing that you were missing was your pack format; 'U' means "UTF-8 character" and would expect an array of Unicode codepoints each represented by a single integer, 'C' expects an array of bytes and that's what we had.
The \354 and so forth are octal escapes, not decimal, so you cannot just write them as 354 to get the integer values of the bytes.
I seems to be a very simple and much needed method. I need to remove all non ASCII characters from a string. e.g © etc. See the following example.
#coding: utf-8
s = " Hello this a mixed string © that I made."
puts s.encoding
puts s.encode
output:
UTF-8
Hello this a mixed str
ing © that I made.
When I feed this to Watir, it produces following error:incompatible character encodings: UTF-8 and ASCII-8BIT
So my problem is that I want to get rid of all non ASCII characters before using it. I will not know which encoding the source string "s" uses.
I have been searching and experimenting for quite some time now.
If I try to use
puts s.encode('ASCII-8BIT')
It gives the error:
: "\xC2\xA9" from UTF-8 to ASCII-8BIT (Encoding::UndefinedConversionError)
You can just literally translate what you asked into a Regexp. You wrote:
I want to get rid of all non ASCII characters
We can rephrase that a little bit:
I want to substitue all characters which don't thave the ASCII property with nothing
And that's a statement that can be directly expressed in a Regexp:
s.gsub!(/\P{ASCII}/, '')
As an alternative, you could also use String#delete!:
s.delete!("^\u{0000}-\u{007F}")
Strip out the characters using regex. This example is in C# but the regex should be the same:
How can you strip non-ASCII characters from a string? (in C#)
Translating it into ruby using gsub should not be difficult.
UTF-8 is a variable-length encoding. When a character occupies one byte, its value coincides with 7-bit ASCII. So why don't you just look for bytes with a '1' in the MSB, and then remove both them and their trailers? A byte beginning with '110' will be followed by one additional byte. A byte beginning with '1110' will be followed by two. And a byte beginning with '11110' will be followed by three, the maximum supported by UTF-8.
This is all just off the top of my head. I could be wrong.