Returns an array containing the quotient and modulus obtained by dividing num
by numeric
.
If q, r = * x.divmod(y)
, then
q = floor(x/y) x = q*y+r
The quotient is rounded toward -infinity, as shown in the following table:
a | b | a.divmod(b) | a/b | a.modulo(b) | a.remainder(b) ------+-----+---------------+---------+-------------+--------------- 13 | 4 | 3, 1 | 3 | 1 | 1 ------+-----+---------------+---------+-------------+--------------- 13 | -4 | -4, -3 | -4 | -3 | 1 ------+-----+---------------+---------+-------------+--------------- -13 | 4 | -4, 3 | -4 | 3 | -1 ------+-----+---------------+---------+-------------+--------------- -13 | -4 | 3, -1 | 3 | -1 | -1 ------+-----+---------------+---------+-------------+--------------- 11.5 | 4 | 2, 3.5 | 2.875 | 3.5 | 3.5 ------+-----+---------------+---------+-------------+--------------- 11.5 | -4 | -3, -0.5 | -2.875 | -0.5 | 3.5 ------+-----+---------------+---------+-------------+--------------- -11.5 | 4 | -3, 0.5 | -2.875 | 0.5 | -3.5 ------+-----+---------------+---------+-------------+--------------- -11.5 | -4 | 2, -3.5 | 2.875 | -3.5 | -3.5
Examples
11.divmod(3) #=> [3, 2] 11.divmod(-3) #=> [-4, -1] 11.divmod(3.5) #=> [3, 0.5] (-11).divmod(3.5) #=> [-4, 3.0] (11.5).divmod(3.5) #=> [3, 1.0]
Returns true
if num
is a Real number. (i.e. not Complex
).
Returns true
if num
is greater than 0.
Returns true
if num
is less than 0.
Returns true
if str has a length of zero.
"hello".empty? #=> false " ".empty? #=> false "".empty? #=> true
Replaces the contents and taintedness of str with the corresponding values in other_str.
s = "hello" #=> "hello" s.replace "world" #=> "world"
Prepend—Prepend the given strings to str.
a = "!" a.prepend("hello ", "world") #=> "hello world!" a #=> "hello world!"
See also String#concat
.
Return the modulo after division of float
by other
.
6543.21.modulo(137) #=> 104.21 6543.21.modulo(137.24) #=> 92.9299999999996
Returns true
if float
is greater than 0.
Returns true
if float
is less than 0.
Resumes the fiber from the point at which the last Fiber.yield
was called, or starts running it if it is the first call to resume
. Arguments passed to resume will be the value of the Fiber.yield
expression or will be passed as block parameters to the fiber’s block if this is the first resume
.
Alternatively, when resume is called it evaluates to the arguments passed to the next Fiber.yield
statement inside the fiber’s block or to the block value if it runs to completion without any Fiber.yield
Returns true if the fiber can still be resumed (or transferred to). After finishing execution of the fiber block this method will always return false. You need to require 'fiber'
before using this method.
Returns the current fiber. You need to require 'fiber'
before using this method. If you are not running in the context of a fiber this method will return the root fiber.
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
Reads the next entry from dir and returns it as a string. Returns nil
at the end of the stream.
d = Dir.new("testdir") d.read #=> "." d.read #=> ".." d.read #=> "config.h"
Repositions dir to the first entry.
d = Dir.new("testdir") d.read #=> "." d.rewind #=> #<Dir:0x401b3fb0> d.read #=> "."
Returns true
if the named file is an empty directory, false
if it is not a directory or non-empty.
Changes permission bits on the named file(s) to the bit pattern represented by mode_int. Actual effects are operating system dependent (see the beginning of this section). On Unix systems, see chmod(2)
for details. Returns the number of files processed.
File.chmod(0644, "testfile", "out") #=> 2
Equivalent to File::chmod
, but does not follow symbolic links (so it will change the permissions associated with the link, not the file referenced by the link). Often not available.
Returns the name of the file referenced by the given link. Not available on all platforms.
File.symlink("testfile", "link2test") #=> 0 File.readlink("link2test") #=> "testfile"
Renames the given file to the new name. Raises a SystemCallError
if the file cannot be renamed.
File.rename("afile", "afile.bak") #=> 0
Returns the real (absolute) pathname of pathname in the actual filesystem not containing symlinks or useless dots.
If dir_string is given, it is used as a base directory for interpreting relative pathname instead of the current directory.
All components of the pathname must exist when this method is called.