Returns the numerator.
Returns the denominator (always positive).
Returns the numerator. The result is machine dependent.
n = 0.3.numerator #=> 5404319552844595 d = 0.3.denominator #=> 18014398509481984 n.fdiv(d) #=> 0.3
See also Float#denominator.
Returns the denominator (always positive). The result is machine dependent.
See also Float#numerator.
Calls the block once for each entry in the named directory, passing the filename of each entry as a parameter to the block.
If no block is given, an enumerator is returned instead.
Dir.foreach("testdir") {|x| puts "Got #{x}" }
produces:
Got . Got .. Got config.h Got main.rb
Returns the numerator.
Rational(7).numerator #=> 7 Rational(7, 1).numerator #=> 7 Rational(9, -4).numerator #=> -9 Rational(-2, -10).numerator #=> 1
Returns the denominator (always positive).
Rational(7).denominator #=> 1 Rational(7, 1).denominator #=> 1 Rational(9, -4).denominator #=> 4 Rational(-2, -10).denominator #=> 5
Returns true if the date is on or after the day of calendar reform.
Date.new(1582,10,15).gregorian? #=> true (Date.new(1582,10,15) - 1).gregorian? #=> false
This method is equivalent to new_start(Date::GREGORIAN).
Executes the block for every line in the named I/O port, where lines are separated by sep.
If no block is given, an enumerator is returned instead.
IO.foreach("testfile") {|x| print "GOT ", x }
produces:
GOT This is line one GOT This is line two GOT This is line three GOT And so on...
If the last argument is a hash, it’s the keyword argument to open. See IO.readlines for details about getline_args. And see also IO.read for details about open_args.
Reorganizes the database file. This operation removes reserved space of elements that have already been deleted. It is only useful after a lot of deletions in the database.
iterates over the list of Addrinfo objects obtained by Addrinfo.getaddrinfo.
Addrinfo.foreach(nil, 80) {|x| p x } #=> #<Addrinfo: 127.0.0.1:80 TCP (:80)> # #<Addrinfo: 127.0.0.1:80 UDP (:80)> # #<Addrinfo: [::1]:80 TCP (:80)> # #<Addrinfo: [::1]:80 UDP (:80)>
Returns true iff there is more data in the string. See eos?. This method is obsolete; use eos? instead.
s = StringScanner.new('test string') s.eos? # These two s.rest? # are opposites.
Returns the “rest” of the string (i.e. everything after the scan pointer). If there is no more data (eos? = true), it returns "".
s.restsize is equivalent to s.rest_size. This method is obsolete; use rest_size instead.
Returns help string of OLE method. If the help string is not found, then the method returns nil.
tobj = WIN32OLE_TYPE.new('Microsoft Internet Controls', 'IWebBrowser') method = WIN32OLE_METHOD.new(tobj, 'Navigate') puts method.helpstring # => Navigates to a URL or file.
Returns help string.
tobj = WIN32OLE_TYPE.new('Microsoft Internet Controls', 'IWebBrowser') puts tobj.helpstring # => Web Browser interface
This method is intended as the primary interface for reading CSV files. You pass a path and any options you wish to set for the read. Each row of file will be passed to the provided block in turn.
The options parameter can be anything CSV::new() understands. This method also understands an additional :encoding parameter that you can use to specify the Encoding of the data in the file to be read. You must provide this unless your data is in Encoding::default_external(). CSV will use this to determine how to parse the data. You may provide a second Encoding to have the data transcoded as it is read. For example, encoding: "UTF-32BE:UTF-8" would read UTF-32BE data from the file but transcode it to UTF-8 before CSV parses it.
Returns the (row, column) cofactor which is obtained by multiplying the first minor by (-1)**(row + column).
Matrix.diagonal(9, 5, -3, 4).cofactor(1, 1) => -108
Creates a single-row matrix from this vector.
Add separator in summary.
Stops execution of the current thread, putting it into a “sleep” state, and schedules execution of another thread.
a = Thread.new { print "a"; Thread.stop; print "c" } sleep 0.1 while a.status!='sleep' print "b" a.run a.join #=> "abc"
Returns true if thr is dead or sleeping.
a = Thread.new { Thread.stop } b = Thread.current a.stop? #=> true b.stop? #=> false
When RubyGems is required, Kernel#require is replaced with our own which is capable of loading gems on demand.
When you call require 'x', this is what happens:
If the file can be loaded from the existing Ruby loadpath, it is.
Otherwise, installed gems are searched for a file that matches. If it’s found in gem ‘y’, that gem is activated (added to the loadpath).
The normal require functionality of returning false if that file has already been loaded is preserved.
Returns true if yield would execute a block in the current context. The iterator? form is mildly deprecated.
def try if block_given? yield else "no block" end end try #=> "no block" try { "hello" } #=> "hello" try do "hello" end #=> "hello"