Float objects represent real numbers using the native
architecture's double-precision floating point representation.
|
instance methods
|
|
Arithmetic operations
|
|
|
Performs various arithmetic operations on flt.
|
flt
|
+ |
aNumeric
|
Addition |
|
flt
|
-- |
aNumeric
|
Subtraction |
|
flt
|
* |
aNumeric
|
Multiplication |
|
flt
|
/ |
aNumeric
|
Division |
|
flt
|
% |
aNumeric
|
Modulo |
|
flt
|
** |
aNumeric
|
Exponentiation |
|
|
<=>
|
flt <=> aNumeric
-> -1, 0, +1
|
|
Returns -1, 0, or +1 depending on whether flt is less
than, equal to, or greater than aNumeric. This is the
basis for the tests in Comparable.
|
|
ceil
|
flt.ceil -> anInteger
|
|
Returns the smallest Integer greater than or equal to flt.
|
1.2.ceil
|
» |
2
|
|
2.0.ceil
|
» |
2
|
|
(-1.2).ceil
|
» |
-1
|
|
(-2.0).ceil
|
» |
-2
|
|
|
finite?
|
flt.finite? -> true or false
|
|
Returns true if flt is a valid IEEE floating point
number (it is not infinite, and nan? is false).
|
|
floor
|
flt.floor -> anInteger
|
|
Returns the largest integer less than or equal to flt.
|
1.2.floor
|
» |
1
|
|
2.0.floor
|
» |
2
|
|
(-1.2).floor
|
» |
-2
|
|
(-2.0).floor
|
» |
-2
|
|
|
infinite?
|
flt.infinite? -> nil, -1,
+1
|
|
Returns nil, -1, or +1 depending on whether flt is finite,
-infinity, or +infinity.
|
(0.0).infinite?
|
» |
nil
|
|
(-1.0/0.0).infinite?
|
» |
-1
|
|
(+1.0/0.0).infinite?
|
» |
1
|
|
|
nan?
|
flt.nan? -> true or false
|
|
Returns true if flt is an invalid IEEE
floating point number.
|
a = -1.0
|
» |
-1.0
|
|
a.nan?
|
» |
false
|
|
a = Math.log(a)
|
» |
NaN
|
|
a.nan?
|
» |
true
|
|
|
round
|
flt.round -> anInteger
|
|
Rounds flt to the nearest integer. Equivalent to:
def round
return floor(self+0.5) if self > 0.0
return ceil(self-0.5) if self < 0.0
return 0.0
end
|
|
1.5.round
|
» |
2
|
|
(-1.5).round
|
» |
-2
|
|
|
to_f
|
flt.to_f -> flt
|
|
Returns flt.
|
|
to_i
|
flt.to_i -> anInteger
|
|
Returns flt truncated to an Integer.
|
|
to_s
|
flt.to_s -> aString
|
|
Returns a string containing a representation of self. As well as
a fixed or exponential form of the number, the call may return
``NaN'', ``Infinity'', and ``-Infinity''.
|
Extracted from the book "Programming Ruby -
The Pragmatic Programmer's Guide"
Copyright
©
2001 by Addison Wesley Longman, Inc. This material may
be distributed only subject to the terms and conditions set forth in
the Open Publication License, v1.0 or later (the latest version is
presently available at http://www.opencontent.org/openpub/)).
Distribution of substantively modified versions of this document is
prohibited without the explicit permission of the copyright holder.
Distribution of the work or derivative of the work in any standard
(paper) book form is prohibited unless prior permission is obtained
from the copyright holder.
