Returns true
if this is a symmetric matrix. Raises an error if matrix is not square.
Returns the determinant of the matrix.
Beware that using Float
values can yield erroneous results because of their lack of precision. Consider using exact types like Rational
or BigDecimal
instead.
Matrix[[7,6], [3,9]].determinant => 45
deprecated; use Matrix#determinant
Returns the conjugate of the matrix.
Matrix[[Complex(1,2), Complex(0,1), 0], [1, 2, 3]] => 1+2i i 0 1 2 3 Matrix[[Complex(1,2), Complex(0,1), 0], [1, 2, 3]].conjugate => 1-2i -i 0 1 2 3
Returns the imaginary part of the matrix.
Matrix[[Complex(1,2), Complex(0,1), 0], [1, 2, 3]] => 1+2i i 0 1 2 3 Matrix[[Complex(1,2), Complex(0,1), 0], [1, 2, 3]].imaginary => 2i i 0 0 0 0
Creates a vector from an Array. The optional second argument specifies whether the array itself or a copy is used internally.
Initializes a new instance and evaluates the optional block in context of the instance. Arguments args
are passed to new
, see there for description of parameters.
This method is deprecated, its behavior corresponds to the older new
method.
Parses command line arguments argv
in order when environment variable POSIXLY_CORRECT is set, and in permutation mode otherwise.
Same as parse
, but removes switches destructively. Non-option arguments remain in argv
.
Parses environment variable env
or its uppercase with splitting like a shell.
env
defaults to the basename of the program.
Returns the number of elements in the match array.
m = /(.)(.)(\d+)(\d)/.match("THX1138.") m.length #=> 5 m.size #=> 5
This is a convenience method which is same as follows:
begin q = PrettyPrint.new(output, maxwidth, newline, &genspace) ... q.flush output end
Returns true if value
is a prime number, else returns false.
value
an arbitrary integer to be checked.
generator
optional. A pseudo-prime generator.
Returns a new set that is a copy of the set, flattening each containing set recursively.
Equivalent to Set#flatten
, but replaces the receiver with the result in place. Returns nil if no modifications were made.
Merges the elements of the given enumerable object to the set and returns self.
Creates a temporary file as usual File
object (not Tempfile
). It doesn’t use finalizer and delegation.
If no block is given, this is similar to Tempfile.new
except creating File
instead of Tempfile
. The created file is not removed automatically. You should use File.unlink
to remove it.
If a block is given, then a File
object will be constructed, and the block is invoked with the object as the argument. The File
object will be automatically closed and the temporary file is removed after the block terminates. The call returns the value of the block.
In any case, all arguments (basename
, tmpdir
, mode
, and **options
) will be treated as Tempfile.new
.
Tempfile.create('foo', '/home/temp') do |f| ... do something with f ... end
Give the thread scheduler a hint to pass execution to another thread. A running thread may or may not switch, it depends on OS and processor.
Returns the status of thr
.
"sleep"
Returned if this thread is sleeping or waiting on I/O
"run"
When this thread is executing
"aborting"
If this thread is aborting
false
When this thread is terminated normally
nil
If terminated with an exception.
a = Thread.new { raise("die now") } b = Thread.new { Thread.stop } c = Thread.new { Thread.exit } d = Thread.new { sleep } d.kill #=> #<Thread:0x401b3678 aborting> a.status #=> nil b.status #=> "sleep" c.status #=> false d.status #=> "aborting" Thread.current.status #=> "run"
Returns true
for a Proc
object for which argument handling is rigid. Such procs are typically generated by lambda
.
A Proc
object generated by proc
ignores extra arguments.
proc {|a,b| [a,b] }.call(1,2,3) #=> [1,2]
It provides nil
for missing arguments.
proc {|a,b| [a,b] }.call(1) #=> [1,nil]
It expands a single array argument.
proc {|a,b| [a,b] }.call([1,2]) #=> [1,2]
A Proc
object generated by lambda
doesn’t have such tricks.
lambda {|a,b| [a,b] }.call(1,2,3) #=> ArgumentError lambda {|a,b| [a,b] }.call(1) #=> ArgumentError lambda {|a,b| [a,b] }.call([1,2]) #=> ArgumentError
Proc#lambda?
is a predicate for the tricks. It returns true
if no tricks apply.
lambda {}.lambda? #=> true proc {}.lambda? #=> false
Proc.new
is the same as proc
.
Proc.new {}.lambda? #=> false
lambda
, proc
and Proc.new
preserve the tricks of a Proc
object given by &
argument.
lambda(&lambda {}).lambda? #=> true proc(&lambda {}).lambda? #=> true Proc.new(&lambda {}).lambda? #=> true lambda(&proc {}).lambda? #=> false proc(&proc {}).lambda? #=> false Proc.new(&proc {}).lambda? #=> false
A Proc
object generated by &
argument has the tricks
def n(&b) b.lambda? end n {} #=> false
The &
argument preserves the tricks if a Proc
object is given by &
argument.
n(&lambda {}) #=> true n(&proc {}) #=> false n(&Proc.new {}) #=> false
A Proc
object converted from a method has no tricks.
def m() end method(:m).to_proc.lambda? #=> true n(&method(:m)) #=> true n(&method(:m).to_proc) #=> true
define_method
is treated the same as method definition. The defined method has no tricks.
class C define_method(:d) {} end C.new.d(1,2) #=> ArgumentError C.new.method(:d).to_proc.lambda? #=> true
define_method
always defines a method without the tricks, even if a non-lambda Proc
object is given. This is the only exception for which the tricks are not preserved.
class C define_method(:e, &proc {}) end C.new.e(1,2) #=> ArgumentError C.new.method(:e).to_proc.lambda? #=> true
This exception ensures that methods never have tricks and makes it easy to have wrappers to define methods that behave as usual.
class C def self.def2(name, &body) define_method(name, &body) end def2(:f) {} end C.new.f(1,2) #=> ArgumentError
The wrapper def2 defines a method which has no tricks.