Block comments appear after a block in the HTML documentation generated by
godoc. Words like "following" should be avoided.
Change-Id: Iedfad67f4b8b9c84f128b98b9b06fa76919af388
Reviewed-on: https://go-review.googlesource.com/14357
Reviewed-by: Rob Pike <r@golang.org>
The previous commit (git 2ae77376) just did golang.org. This one
includes golang.org subdomains like blog, play, and build.
Change-Id: I4469f7b307ae2a12ea89323422044e604c5133ae
Reviewed-on: https://go-review.googlesource.com/12071
Reviewed-by: Rob Pike <r@golang.org>
- (*Float).Scan conflicted with fmt.Scanner.Scan; it was also only used
internally. Removed it, as well as the companion ScanFloat function.
- (*Float).Parse (and thus ParseFloat) can now also parse infinities.
As a result, more code could be simplified.
- Fixed a bug in rounding (round may implicitly be called for infinite
values). Found via existing test cases, after simplifying some code.
- Added more test cases.
Fixes issue #10938.
Change-Id: I1df97821654f034965ba8b82b272e52e6dc427f1
Reviewed-on: https://go-review.googlesource.com/10498
Reviewed-by: Alan Donovan <adonovan@google.com>
This paves the way for a fmt-compatible (*Float).Format method.
A better name then Text is still desirable (suggestions welcome).
This is partly fixing issue #10938.
Change-Id: I59c20a8cee11f5dba059fe0f38b414fe75f2ab13
Reviewed-on: https://go-review.googlesource.com/10493
Reviewed-by: Alan Donovan <adonovan@google.com>
Float.Format supports the 'b' and 'p' format, both of which print
a binary ('p') exponent. The 'b' format always printed a sign ('+'
or '-') for the exponent; the 'p' format only printed a negative
sign for the exponent. This change makes the two consistent. It
also makes the 'p' format easier to read if the exponent is >= 0.
Also:
- Comments added elsewhere.
Change-Id: Ifd2e01bdafb3043345972ca22a90248d055bd29b
Reviewed-on: https://go-review.googlesource.com/10359
Reviewed-by: Alan Donovan <adonovan@google.com>
- This change uses the same code as for Float32 and fixes the case
of a number that gets rounded up to the smallest denormal.
- Enabled correspoding test case.
Change-Id: I8aac874a566cd727863a82717854f603fbdc26c6
Reviewed-on: https://go-review.googlesource.com/10352
Reviewed-by: Alan Donovan <adonovan@google.com>
The existing code was incorrect for numbers that after rounding would
become the smallest denormal float32 (instead the result was 0). This
caused all.bash to fail if Float32() were used in the compiler for
constant arithmetic (there's currently a work-around - see also issue
10321.
This change fixes the implementation of Float.Float32 and adds
corresponding test cases. Float32 and Float64 diverge at this point.
For ease of review, this change only fixes Float32. Float64 will be
made to match in a subsequent change.
Fixes#10321.
Change-Id: Iccafe37c1593a4946bc552e4ad2045f69be62d80
Reviewed-on: https://go-review.googlesource.com/10350
Reviewed-by: Alan Donovan <adonovan@google.com>
There was no way to get to the error message before.
Change-Id: I4aa9d3d9f468c33f9996295bafcbed097de0389f
Reviewed-on: https://go-review.googlesource.com/8660
Reviewed-by: Alan Donovan <adonovan@google.com>
NaNs make the API more complicated for no real good reasons.
There are few operations that produce NaNs with IEEE arithmetic,
there's no need to copy the behavior. It's easy to test for these
scenarios and avoid them (on the other hand, it's not easy to test
for overflow or underflow, so we want to keep +/-Inf).
Also:
- renamed IsNeg -> Signbit (clearer, especially for x == -0)
- removed IsZero (Sign() == 0 is sufficient and efficient)
- removed IsFinite (now same as !IsInf)
Change-Id: I3f3b4445c325d9bbb1bf46ce2e298a6aeb498e07
Reviewed-on: https://go-review.googlesource.com/8280
Reviewed-by: Alan Donovan <adonovan@google.com>
- fix bounds checks for exponent range of denormalized numbers
- use correct rounding precision for denormalized numbers
- added extra tests
Change-Id: I6be56399afd0d9a603300a2e44b5539e08d6f592
Reviewed-on: https://go-review.googlesource.com/8096
Reviewed-by: Alan Donovan <adonovan@google.com>
Float.Cmp used to return a value < 0, 0, or > 0 depending on how
arguments x, y compared against each other. With the possibility
of NaNs, the result was changed into an Accuracy (to include Undef).
Consequently, Float.Cmp results could still be compared for (in-)
equality with 0, but comparing if < 0 or > 0 would provide the
wrong answer w/o any obvious notice by the compiler.
This change wraps Float.Cmp results into a struct and accessors
are used to access the desired result. This prevents incorrect
use.
Change-Id: I34e6a6c1859251ec99b5cf953e82542025ace56f
Reviewed-on: https://go-review.googlesource.com/7526
Reviewed-by: Rob Pike <r@golang.org>
Also:
- Implemented NewFloat convenience factory function (analogous to
NewInt and NewRat).
- Implemented convenience accessors for Accuracy values returned
from Float.Cmp.
- Added test and example.
Change-Id: I985bb4f86e6def222d4b2505417250d29a39c60e
Reviewed-on: https://go-review.googlesource.com/6970
Reviewed-by: Alan Donovan <adonovan@google.com>
This is a fairly significant _internal_ representation change. Instead
of encoding 0, finite, infinite, and NaN values with special mantissa
and exponent values, a new (1 byte) 'form' field is used (without making
the Float struct bigger). The form field permits simpler and faster
case distinctions. As a side benefit, for zero and non-finite floats,
fewer fields need to be set. Also, the exponent range is not the full
int32 range (in the old format, infExp and nanExp were used to represent
Inf and NaN values and tests for those values sometimes didn't test
for the empty mantissa, so the range was reduced by 2 values).
The correspondence between the old and new fields is as follows.
Old representation:
x neg mant exp
---------------------------------------------------------------
+/-0 sign empty 0
0 < |x| < +Inf sign mantissa exponent
+/-Inf sign empty infExp
NaN false empty nanExp
New representation (- stands for ignored fields):
x neg mant exp form
---------------------------------------------------------------
+/-0 sign - - zero
0 < |x| < +Inf sign mantissa exponent finite
+/-Inf sign - - inf
NaN - - - nan
Client should not be affected by this change.
Change-Id: I7e355894d602ceb23f9ec01da755fe6e0386b101
Reviewed-on: https://go-review.googlesource.com/6870
Reviewed-by: Alan Donovan <adonovan@google.com>
Shifts are trivially implemented by combining
Float.MantExp and Float.SetMantExp.
Change-Id: Ia2fb49297d8ea7aa7d64c8b1318dc3dc7c8af2f7
Reviewed-on: https://go-review.googlesource.com/6671
Reviewed-by: Alan Donovan <adonovan@google.com>
This change represents Accuracy as a bit pattern rather than
an ordered value; with a new value Undef which is both Below
and Above.
Change-Id: Ibb96294c1417fb3cf2c3cf2374c993b0a4e106b3
Reviewed-on: https://go-review.googlesource.com/6650
Reviewed-by: Alan Donovan <adonovan@google.com>
This change introduces NaNs (for situations like Inf-Inf, etc.).
The implementation is incomplete (the four basic operations produce
a NaN if any of the operands is an Inf or a NaN); and some operations
produce incorrect accuracy for NaN arguments. These are known bugs
which are documented.
Change-Id: Ia88841209e47930681cef19f113e178f92ceeb33
Reviewed-on: https://go-review.googlesource.com/6540
Reviewed-by: Alan Donovan <adonovan@google.com>
MinPrec returns the minimum precision required to represent a Float
without loss of precision. Added test.
Change-Id: I466c8e492dcdd59fae854fc4e71ef9b1add7d817
Reviewed-on: https://go-review.googlesource.com/6010
Reviewed-by: Alan Donovan <adonovan@google.com>
Some rounding modes are affected by the sign of the value to
be rounded. Make sure the sign is set before round is called.
Added tests (that failed before the fix).
Change-Id: Idd09b8fcbab89894fede0b9bc922cda5ddc87930
Reviewed-on: https://go-review.googlesource.com/4876
Reviewed-by: Rob Pike <r@golang.org>
Also: remove NewFloat - not needed anymore. Work-around for places
where has been used so far:
NewFloat(x, prec, mode) === new(Float).SetMode(mode).SetPrec(prec).SetFloat64(x)
However, if mode == ToNearestEven, SetMode is not needed. SetPrec
is needed if the default precision (53 after SetFloat64) is not
adequate.
TBR adonovan
Change-Id: Ifda12c479ba157f2dea306c32b47c7afbf31e759
Reviewed-on: https://go-review.googlesource.com/4842
Reviewed-by: Robert Griesemer <gri@golang.org>
Also:
- make representation more flexible (no need to store trailing 0 digits to match precision)
- simplify rounding as a consequence
- minor related fixes
TBR adonovan
Change-Id: Ie91075990688b506d28371ec3b633b8267397ebb
Reviewed-on: https://go-review.googlesource.com/4841
Reviewed-by: Rob Pike <r@golang.org>
