Returns the real 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]].real
=> 1 0 0
1 2 3
Collects (as in Enumerable#collect) over the elements of this vector and v in conjunction.
Like Array#collect.
Returns a new vector with the same direction but with norm 1.
v = Vector[5,8,2].normalize # => Vector[0.5184758473652127, 0.8295613557843402, 0.20739033894608505] v.norm => 1.0
Returns the value as a rational. The optional argument eps is always ignored.
Looks up the first IP address for name.
Looks up all IP address for name.
Looks up the first IP address for name.
Looks up all IP address for name.
Replaces the elements with ones returned by collect(). Returns an enumerator if no block is given.
Sends the given signal to the given job
Basically the same as ::new. However, if class Thread is subclassed, then calling start in that subclass will not invoke the subclass’s initialize method.
Causes the given thread to exit, see also Thread::exit.
count = 0 a = Thread.new { loop { count += 1 } } sleep(0.1) #=> 0 Thread.kill(a) #=> #<Thread:0x401b3d30 dead> count #=> 93947 a.alive? #=> false
Waits for thr to complete, using join, and returns its value or raises the exception which terminated the thread.
a = Thread.new { 2 + 2 } a.value #=> 4 b = Thread.new { raise 'something went wrong' } b.value #=> RuntimeError: something went wrong
Terminates thr and schedules another thread to be run.
If this thread is already marked to be killed, exit returns the Thread.
If this is the main thread, or the last thread, exits the process.
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 if thr is running or sleeping.
thr = Thread.new { } thr.join #=> #<Thread:0x401b3fb0 dead> Thread.current.alive? #=> true thr.alive? #=> false
Return the tag object which was called for.
Return the return value which was called for.
Returns internal information of TracePoint.
The contents of the returned value are implementation specific. It may be changed in future.
This method is only for debugging TracePoint itself.
See also BigDecimal.new
Returns x/y;
Rational(1, 2) #=> (1/2) Rational('1/2') #=> (1/2) Rational(nil) #=> TypeError Rational(1, nil) #=> TypeError
Syntax of string form:
string form = extra spaces , rational , extra spaces ;
rational = [ sign ] , unsigned rational ;
unsigned rational = numerator | numerator , "/" , denominator ;
numerator = integer part | fractional part | integer part , fractional part ;
denominator = digits ;
integer part = digits ;
fractional part = "." , digits , [ ( "e" | "E" ) , [ sign ] , digits ] ;
sign = "-" | "+" ;
digits = digit , { digit | "_" , digit } ;
digit = "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9" ;
extra spaces = ? \s* ? ;
See String#to_r.
Evaluates the Ruby expression(s) in string. If binding is given, which must be a Binding object, the evaluation is performed in its context. If the optional filename and lineno parameters are present, they will be used when reporting syntax errors.
def get_binding(str) return binding end str = "hello" eval "str + ' Fred'" #=> "hello Fred" eval "str + ' Fred'", get_binding("bye") #=> "bye Fred"
Returns a new array with the results of running block once for every element in enum.
If no block is given, an enumerator is returned instead.
(1..4).map { |i| i*i } #=> [1, 4, 9, 16] (1..4).collect { "cat" } #=> ["cat", "cat", "cat", "cat"]