Changes the encoding to encoding and returns self.
Returns true for a string which is encoded correctly.
"\xc2\xa1".force_encoding("UTF-8").valid_encoding? #=> true "\xc2".force_encoding("UTF-8").valid_encoding? #=> false "\x80".force_encoding("UTF-8").valid_encoding? #=> false
Converts a BigDecimal to a String of the form “nnnnnn.mmm”. This method is deprecated; use BigDecimal#to_s(“F”) instead.
require 'bigdecimal/util' d = BigDecimal("3.14") d.to_digits # => "3.14"
Returns true if the given ordinal date is valid, and false if not.
Date.valid_ordinal?(2001,34) #=> true Date.valid_ordinal?(2001,366) #=> false
Calls the given block once for each character in ios, passing the character as an argument. The stream must be opened for reading or an IOError will be raised.
If no block is given, an enumerator is returned instead.
f = File.new("testfile") f.each_char {|c| print c, ' ' } #=> #<File:testfile>
Returns the Encoding object that represents the encoding of the file. If io is in write mode and no encoding is specified, returns nil.
Returns the Encoding of the internal string if conversion is specified. Otherwise returns nil.
If single argument is specified, read string from io is tagged with the encoding specified. If encoding is a colon separated two encoding names “A:B”, the read string is converted from encoding A (external encoding) to encoding B (internal encoding), then tagged with B. If two arguments are specified, those must be encoding objects or encoding names, and the first one is the external encoding, and the second one is the internal encoding. If the external encoding and the internal encoding is specified, optional hash argument specify the conversion option.
Returns false if rxp is applicable to a string with any ASCII compatible encoding. Returns true otherwise.
r = /a/ r.fixed_encoding? #=> false r =~ "\u{6666} a" #=> 2 r =~ "\xa1\xa2 a".force_encoding("euc-jp") #=> 2 r =~ "abc".force_encoding("euc-jp") #=> 0 r = /a/u r.fixed_encoding? #=> true r.encoding #=> #<Encoding:UTF-8> r =~ "\u{6666} a" #=> 2 r =~ "\xa1\xa2".force_encoding("euc-jp") #=> Encoding::CompatibilityError r =~ "abc".force_encoding("euc-jp") #=> 0 r = /\u{6666}/ r.fixed_encoding? #=> true r.encoding #=> #<Encoding:UTF-8> r =~ "\u{6666} a" #=> 0 r =~ "\xa1\xa2".force_encoding("euc-jp") #=> Encoding::CompatibilityError r =~ "abc".force_encoding("euc-jp") #=> nil
Iterates over the children of the directory (files and subdirectories, not recursive).
It yields Pathname object for each child.
By default, the yielded pathnames will have enough information to access the files.
If you set with_directory to false, then the returned pathnames will contain the filename only.
Pathname("/usr/local").each_child {|f| p f } #=> #<Pathname:/usr/local/share> # #<Pathname:/usr/local/bin> # #<Pathname:/usr/local/games> # #<Pathname:/usr/local/lib> # #<Pathname:/usr/local/include> # #<Pathname:/usr/local/sbin> # #<Pathname:/usr/local/src> # #<Pathname:/usr/local/man> Pathname("/usr/local").each_child(false) {|f| p f } #=> #<Pathname:share> # #<Pathname:bin> # #<Pathname:games> # #<Pathname:lib> # #<Pathname:include> # #<Pathname:sbin> # #<Pathname:src> # #<Pathname:man>
Note that the results never contain the entries . and .. in the directory because they are not children.
Returns the Encoding object that represents the encoding of the file. If the stream is write mode and no encoding is specified, returns nil.
Returns the Encoding of the internal string if conversion is specified. Otherwise returns nil.
Specify the encoding of the StringIO as ext_enc. Use the default external encoding if ext_enc is nil. 2nd argument int_enc and optional hash opt argument are ignored; they are for API compatibility to IO.
Iterates over each character of each file in ARGF.
This method allows you to treat the files supplied on the command line as a single file consisting of the concatenation of each named file. After the last character of the first file has been returned, the first character of the second file is returned. The ARGF.filename method can be used to determine the name of the file in which the current character appears.
If no block is given, an enumerator is returned instead.
Returns the external encoding for files read from ARGF as an Encoding object. The external encoding is the encoding of the text as stored in a file. Contrast with ARGF.internal_encoding, which is the encoding used to represent this text within Ruby.
To set the external encoding use ARGF.set_encoding.
For example:
ARGF.external_encoding #=> #<Encoding:UTF-8>
Returns the internal encoding for strings read from ARGF as an Encoding object.
If ARGF.set_encoding has been called with two encoding names, the second is returned. Otherwise, if Encoding.default_external has been set, that value is returned. Failing that, if a default external encoding was specified on the command-line, that value is used. If the encoding is unknown, nil is returned.
If single argument is specified, strings read from ARGF are tagged with the encoding specified.
If two encoding names separated by a colon are given, e.g. “ascii:utf-8”, the read string is converted from the first encoding (external encoding) to the second encoding (internal encoding), then tagged with the second encoding.
If two arguments are specified, they must be encoding objects or encoding names. Again, the first specifies the external encoding; the second specifies the internal encoding.
If the external encoding and the internal encoding are specified, the optional Hash argument can be used to adjust the conversion process. The structure of this hash is explained in the String#encode documentation.
For example:
ARGF.set_encoding('ascii') # Tag the input as US-ASCII text ARGF.set_encoding(Encoding::UTF_8) # Tag the input as UTF-8 text ARGF.set_encoding('utf-8','ascii') # Transcode the input from US-ASCII # to UTF-8.
Returns the encoding of the internal IO object.
Returns the submatrix obtained by deleting the specified row and column.
Matrix.diagonal(9, 5, -3, 4).first_minor(1, 2)
=> 9 0 0
0 0 0
0 0 4
Returns additional info.
Returns the factorization of value.
value
An arbitrary integer.
generator
Optional. A pseudo-prime generator. generator.succ must return the next pseudo-prime number in the ascending order. It must generate all prime numbers, but may also generate non prime numbers too.
ZeroDivisionError
when value is zero.
For an arbitrary integer:
n = p_1**e_1 * p_2**e_2 * .... * p_n**e_n,
prime_division(n) returns:
[[p_1, e_1], [p_2, e_2], ...., [p_n, e_n]]. Prime.prime_division(12) #=> [[2,2], [3,1]]
Returns whether or not the asynchronous queue is empty.
Since Thread::handle_interrupt can be used to defer asynchronous events, this method can be used to determine if there are any deferred events.
If you find this method returns true, then you may finish :never blocks.
For example, the following method processes deferred asynchronous events immediately.
def Thread.kick_interrupt_immediately Thread.handle_interrupt(Object => :immediate) { Thread.pass } end
If error is given, then check only for error type deferred events.
th = Thread.new{
Thread.handle_interrupt(RuntimeError => :on_blocking){
while true
...
# reach safe point to invoke interrupt
if Thread.pending_interrupt?
Thread.handle_interrupt(Object => :immediate){}
end
...
end
}
}
...
th.raise # stop thread
This example can also be written as the following, which you should use to avoid asynchronous interrupts.
flag = true
th = Thread.new{
Thread.handle_interrupt(RuntimeError => :on_blocking){
while true
...
# reach safe point to invoke interrupt
break if flag == false
...
end
}
}
...
flag = false # stop thread