/usr/share/GNUstep/Documentation/Developer/Base/Reference/NSDecimalNumber.gsdoc is in gnustep-base-doc 1.25.1-2ubuntu3.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 | <?xml version="1.0"?>
<!DOCTYPE gsdoc PUBLIC "-//GNUstep//DTD gsdoc 1.0.4//EN" "http://www.gnustep.org/gsdoc-1_0_4.dtd">
<gsdoc base="NSDecimalNumber" up="Base">
<head>
<title>NSDecimalNumber class reference</title>
<author name="Fred Kiefer">
<email address="FredKiefer@gmx.de">
FredKiefer@gmx.de
</email>
</author>
<copy>2000 Free Software Foundation, Inc.</copy>
</head>
<body>
<front><contents /></front>
<chapter>
<heading>
Software documentation for the NSDecimalNumber class
</heading>
<class name="NSDecimalNumber" super="NSNumber" ovadd="10.0.0">
<declared>Foundation/NSDecimalNumber.h</declared>
<conform>NSDecimalNumberBehaviors</conform>
<desc>
<p>
<strong>Class</strong> that implements a number of
methods for performing decimal arithmetic to
arbitrary precision. The behavior in terms of
rounding choices and exception handling may be
customized using the
<ref type="class" id="NSDecimalNumberHandler">NSDecimalNumberHandler</ref>class, and defaults to <ref type="method" id="+defaultDecimalNumberHandler" class="NSDecimalNumberHandler">[NSDecimalNumberHandler +defaultDecimalNumberHandler]</ref>.</p>
<p>
Equivalent functionality to the
<code>NSDecimalNumber</code> class may be accessed
through functions, mostly named
<code>NSDecimalXXX</code>, e.g.,
<ref type="function" id="NSDecimalMin">
NSDecimalMin()
</ref>
. Both the class and the functions use a structure
called <code>NSDecimal</code>.
</p>
<p>
Note that instances of <code>NSDecimalNumber</code>
are immutable.
</p>
</desc>
<ivariable type="NSDecimal" name="data" validity="protected" ovadd="10.0.0">
<desc>
<em>Description forthcoming.</em>
</desc>
</ivariable>
<method type="NSDecimalNumber*" factory="yes" ovadd="10.0.0">
<sel>decimalNumberWithDecimal:</sel>
<arg type="NSDecimal">decimal</arg>
<desc>
New instance with given value. Note an NSDecimal may be
created using the function
<ref type="function" id="NSDecimalFromString">
NSDecimalFromString()
</ref>
.
</desc>
</method>
<method type="NSDecimalNumber*" factory="yes" ovadd="10.0.0">
<sel>decimalNumberWithMantissa:</sel>
<arg type="unsigned long long">mantissa</arg>
<sel>exponent:</sel>
<arg type="short">exponent</arg>
<sel>isNegative:</sel>
<arg type="BOOL">isNegative</arg>
<desc>
New instance by component. Note that the precision of
this initializer is limited.
</desc>
</method>
<method type="NSDecimalNumber*" factory="yes" ovadd="10.0.0">
<sel>decimalNumberWithString:</sel>
<arg type="NSString*">numericString</arg>
<desc>
New instance from string. Arbitrary precision is
preserved, though calling one of the
<code>decimalNumberBy...</code> methods will return
a result constrained by the current
<em><code>scale</code></em>. Number format is parsed
according to current default locale.
</desc>
</method>
<method type="NSDecimalNumber*" factory="yes" ovadd="10.0.0">
<sel>decimalNumberWithString:</sel>
<arg type="NSString*">numericString</arg>
<sel>locale:</sel>
<arg type="NSDictionary*">locale</arg>
<desc>
New instance from string. Arbitrary precision is
preserved, though calling one of the
<code>decimalNumberBy...</code> methods will return
a result constrained by the current
<em><code>scale</code></em>. Number format is parsed
according to given <var>locale</var>.
</desc>
</method>
<method type="id<NSDecimalNumberBehaviors>" factory="yes" ovadd="10.0.0">
<sel>defaultBehavior</sel>
<desc>
Returns the default rounding/precision/exception
handling behavior, which is same as
<ref type="method" id="+defaultDecimalNumberHandler" class="NSDecimalNumberHandler">[NSDecimalNumberHandler +defaultDecimalNumberHandler]</ref> unless it has been explicitly set otherwise.
</desc>
</method>
<method type="NSDecimalNumber*" factory="yes" ovadd="10.0.0">
<sel>maximumDecimalNumber</sel>
<desc>
Return maximum positive value that can be
represented.
</desc>
</method>
<method type="NSDecimalNumber*" factory="yes" ovadd="10.0.0">
<sel>minimumDecimalNumber</sel>
<desc>
Return minimum negative value (<em>not</em> the
smallest positive value) that can be represented.
</desc>
</method>
<method type="NSDecimalNumber*" factory="yes" ovadd="10.0.0">
<sel>notANumber</sel>
<desc>
Return a fixed value representing an NaN.
</desc>
</method>
<method type="NSDecimalNumber*" factory="yes" ovadd="10.0.0">
<sel>one</sel>
<desc>
Return a constant object with a value of one.
</desc>
</method>
<method type="void" factory="yes" ovadd="10.0.0">
<sel>setDefaultBehavior:</sel>
<arg type="id<NSDecimalNumberBehaviors>">behavior</arg>
<desc>
Sets the default rounding/precision/exception handling
<var>behavior</var> to the given <var>behavior</var>.
If this is not called, <var>behavior</var> defaults to
<ref type="method" id="+defaultDecimalNumberHandler" class="NSDecimalNumberHandler">[NSDecimalNumberHandler +defaultDecimalNumberHandler]</ref>.
</desc>
</method>
<method type="NSDecimalNumber*" factory="yes" ovadd="10.0.0">
<sel>zero</sel>
<desc>
Return a constant object with a value of zero.
</desc>
</method>
<method type="NSComparisonResult" ovadd="10.0.0">
<sel>compare:</sel>
<arg type="NSNumber*">decimalNumber</arg>
<desc>
Compares with other number, returning less,
greater, or equal.
</desc>
</method>
<method type="NSDecimalNumber*" ovadd="10.0.0">
<sel>decimalNumberByAdding:</sel>
<arg type="NSDecimalNumber*">decimalNumber</arg>
<desc>
Adds self to <var>decimalNumber</var> and returns new
result, using
<ref type="method" id="+defaultBehavior">
+defaultBehavior
</ref>
for rounding/precision/error handling.
</desc>
</method>
<method type="NSDecimalNumber*" ovadd="10.0.0">
<sel>decimalNumberByAdding:</sel>
<arg type="NSDecimalNumber*">decimalNumber</arg>
<sel>withBehavior:</sel>
<arg type="id<NSDecimalNumberBehaviors>">behavior</arg>
<desc>
Adds self to <var>decimalNumber</var> and returns new
result, using given <var>behavior</var> for
rounding/precision/error handling.
</desc>
</method>
<method type="NSDecimalNumber*" ovadd="10.0.0">
<sel>decimalNumberByDividingBy:</sel>
<arg type="NSDecimalNumber*">decimalNumber</arg>
<desc>
Divides self by <var>decimalNumber</var> and
returns new result, using
<ref type="method" id="+defaultBehavior">
+defaultBehavior
</ref>
for rounding/precision/error handling.
</desc>
</method>
<method type="NSDecimalNumber*" ovadd="10.0.0">
<sel>decimalNumberByDividingBy:</sel>
<arg type="NSDecimalNumber*">decimalNumber</arg>
<sel>withBehavior:</sel>
<arg type="id<NSDecimalNumberBehaviors>">behavior</arg>
<desc>
Divides self by <var>decimalNumber</var> and
returns new result, using given <var>behavior</var>
for rounding/precision/error handling.
</desc>
</method>
<method type="NSDecimalNumber*" ovadd="10.0.0">
<sel>decimalNumberByMultiplyingBy:</sel>
<arg type="NSDecimalNumber*">decimalNumber</arg>
<desc>
Multiplies self by <var>decimalNumber</var> and
returns new result, using
<ref type="method" id="+defaultBehavior">
+defaultBehavior
</ref>
for rounding/precision/error handling.
</desc>
</method>
<method type="NSDecimalNumber*" ovadd="10.0.0">
<sel>decimalNumberByMultiplyingBy:</sel>
<arg type="NSDecimalNumber*">decimalNumber</arg>
<sel>withBehavior:</sel>
<arg type="id<NSDecimalNumberBehaviors>">behavior</arg>
<desc>
Multiplies self by <var>decimalNumber</var> and
returns new result, using given <var>behavior</var>
for rounding/precision/error handling.
</desc>
</method>
<method type="NSDecimalNumber*" ovadd="10.0.0">
<sel>decimalNumberByMultiplyingByPowerOf10:</sel>
<arg type="short">power</arg>
<desc>
Multiplies self by given <var>power</var> of 10
and returns new result, using
<ref type="method" id="+defaultBehavior">
+defaultBehavior
</ref>
for rounding/precision/error handling.
</desc>
</method>
<method type="NSDecimalNumber*" ovadd="10.0.0">
<sel>decimalNumberByMultiplyingByPowerOf10:</sel>
<arg type="short">power</arg>
<sel>withBehavior:</sel>
<arg type="id<NSDecimalNumberBehaviors>">behavior</arg>
<desc>
Multiplies self by given <var>power</var> of 10
and returns new result, using given <var>behavior</var>
for rounding/precision/error handling.
</desc>
</method>
<method type="NSDecimalNumber*" ovadd="10.0.0">
<sel>decimalNumberByRaisingToPower:</sel>
<arg type="NSUInteger">power</arg>
<desc>
Raises self to given positive integer
<var>power</var> and returns new result, using
<ref type="method" id="+defaultBehavior">
+defaultBehavior
</ref>
for rounding/precision/error handling.
</desc>
</method>
<method type="NSDecimalNumber*" ovadd="10.0.0">
<sel>decimalNumberByRaisingToPower:</sel>
<arg type="NSUInteger">power</arg>
<sel>withBehavior:</sel>
<arg type="id<NSDecimalNumberBehaviors>">behavior</arg>
<desc>
Raises self to given positive integer
<var>power</var> and returns new result, using given
<var>behavior</var> for rounding/precision/error
handling.
</desc>
</method>
<method type="NSDecimalNumber*" ovadd="10.0.0">
<sel>decimalNumberByRoundingAccordingToBehavior:</sel>
<arg type="id<NSDecimalNumberBehaviors>">behavior</arg>
<desc>
Returns rounded version of underlying decimal.
</desc>
</method>
<method type="NSDecimalNumber*" ovadd="10.0.0">
<sel>decimalNumberBySubtracting:</sel>
<arg type="NSDecimalNumber*">decimalNumber</arg>
<desc>
Subtracts <var>decimalNumber</var> from self and
returns new result, using
<ref type="method" id="+defaultBehavior">
+defaultBehavior
</ref>
for rounding/precision/error handling.
</desc>
</method>
<method type="NSDecimalNumber*" ovadd="10.0.0">
<sel>decimalNumberBySubtracting:</sel>
<arg type="NSDecimalNumber*">decimalNumber</arg>
<sel>withBehavior:</sel>
<arg type="id<NSDecimalNumberBehaviors>">behavior</arg>
<desc>
Subtracts <var>decimalNumber</var> from self and
returns new result, using given <var>behavior</var>
for rounding/precision/error handling.
</desc>
</method>
<method type="NSDecimal" ovadd="10.0.0">
<sel>decimalValue</sel>
<desc>
Return underlying value as an <code>NSDecimal</code>
structure.
</desc>
</method>
<method type="NSString*" ovadd="10.0.0">
<sel>descriptionWithLocale:</sel>
<arg type="id">locale</arg>
<desc>
Returns string version of number formatted
according to <var>locale</var>.
</desc>
</method>
<method type="double" ovadd="10.0.0">
<sel>doubleValue</sel>
<desc>
Returns underlying value as a
<code><strong>double</strong></code>, which may be
an approximation if precision greater than the default
of 38.
</desc>
</method>
<method type="id" ovadd="10.0.0">
<sel>initWithDecimal:</sel>
<arg type="NSDecimal">decimal</arg>
<desc>
Initialize with given value. Note an NSDecimal
may be created using the function
<ref type="function" id="NSDecimalFromString">
NSDecimalFromString()
</ref>
.
</desc>
</method>
<method type="id" ovadd="10.0.0">
<sel>initWithMantissa:</sel>
<arg type="unsigned long long">mantissa</arg>
<sel>exponent:</sel>
<arg type="short">exponent</arg>
<sel>isNegative:</sel>
<arg type="BOOL">flag</arg>
<desc>
Initialize by component. Note that the precision
of this initializer is limited.
</desc>
</method>
<method type="id" ovadd="10.0.0">
<sel>initWithString:</sel>
<arg type="NSString*">numberValue</arg>
<desc>
Initialize from string. Arbitrary precision is
preserved, though calling one of the
<code>decimalNumberBy...</code> methods will return
a result constrained by the current
<em><code>scale</code></em>. Number format is parsed
according to current default locale.
</desc>
</method>
<method type="id" ovadd="10.0.0">
<sel>initWithString:</sel>
<arg type="NSString*">numberValue</arg>
<sel>locale:</sel>
<arg type="NSDictionary*">locale</arg>
<desc>
Initialize from string. Arbitrary precision is
preserved, though calling one of the
<code>decimalNumberBy...</code> methods will return
a result constrained by the current
<em><code>scale</code></em>. Number format is parsed
according to given <var>locale</var>.
</desc>
</method>
<method type="const char*" ovadd="10.0.0">
<sel>objCType</sel>
<desc>
Returns the Objective-C type (
<code>@encode(...)</code> compatible) of the data
contained <code>NSDecimalNumber</code>, which is
by convention "d" (for <strong>double</strong>), even
though this is not strictly accurate.
</desc>
</method>
</class>
</chapter>
<chapter>
<heading>
Software documentation for the NSDecimalNumberHandler
class
</heading>
<class name="NSDecimalNumberHandler" super="NSObject" ovadd="10.0.0">
<declared>Foundation/NSDecimalNumber.h</declared>
<conform>NSDecimalNumberBehaviors</conform>
<desc>
A utility class adopting
<ref type="protocol" id="(NSDecimalNumberBehaviors)"><NSDecimalNumberBehaviors></ref>
protocol. Can be used to control
<ref type="class" id="NSDecimalNumber">NSDecimalNumber</ref>
rounding and exception-handling behavior, by
passing an instance as an argument to any
<ref type="class" id="NSDecimalNumber">NSDecimalNumber</ref>
method ending with <code>...Behavior:</code>.
</desc>
<ivariable type="BOOL" name="_raiseOnDivideByZero" validity="protected" ovadd="10.0.0">
<desc>
<em>Warning</em> the underscore at the start of the
name of this instance variable indicates that, even
though it is not technically <em>private</em>, it is
intended for internal use within the package, and
you should not use the variable in other code.
</desc>
</ivariable>
<ivariable type="BOOL" name="_raiseOnExactness" validity="protected" ovadd="10.0.0">
<desc>
<em>Warning</em> the underscore at the start of the
name of this instance variable indicates that, even
though it is not technically <em>private</em>, it is
intended for internal use within the package, and
you should not use the variable in other code.
</desc>
</ivariable>
<ivariable type="BOOL" name="_raiseOnOverflow" validity="protected" ovadd="10.0.0">
<desc>
<em>Warning</em> the underscore at the start of the
name of this instance variable indicates that, even
though it is not technically <em>private</em>, it is
intended for internal use within the package, and
you should not use the variable in other code.
</desc>
</ivariable>
<ivariable type="BOOL" name="_raiseOnUnderflow" validity="protected" ovadd="10.0.0">
<desc>
<em>Warning</em> the underscore at the start of the
name of this instance variable indicates that, even
though it is not technically <em>private</em>, it is
intended for internal use within the package, and
you should not use the variable in other code.
</desc>
</ivariable>
<ivariable type="NSRoundingMode" name="_roundingMode" validity="protected" ovadd="10.0.0">
<desc>
<em>Warning</em> the underscore at the start of the
name of this instance variable indicates that, even
though it is not technically <em>private</em>, it is
intended for internal use within the package, and
you should not use the variable in other code.
</desc>
</ivariable>
<ivariable type="short int" name="_scale" validity="protected" ovadd="10.0.0">
<desc>
<em>Warning</em> the underscore at the start of the
name of this instance variable indicates that, even
though it is not technically <em>private</em>, it is
intended for internal use within the package, and
you should not use the variable in other code.
</desc>
</ivariable>
<method type="id" factory="yes" ovadd="10.0.0">
<sel>decimalNumberHandlerWithRoundingMode:</sel>
<arg type="NSRoundingMode">roundingMode</arg>
<sel>scale:</sel>
<arg type="short">scale</arg>
<sel>raiseOnExactness:</sel>
<arg type="BOOL">raiseOnExactness</arg>
<sel>raiseOnOverflow:</sel>
<arg type="BOOL">raiseOnOverflow</arg>
<sel>raiseOnUnderflow:</sel>
<arg type="BOOL">raiseOnUnderflow</arg>
<sel>raiseOnDivideByZero:</sel>
<arg type="BOOL">raiseOnDivideByZero</arg>
<desc>
Constructor setting all behavior. (For more
precise control over error handling, create your
own class implementing the
<ref type="protocol" id="(NSDecimalNumberBehaviors)"><NSDecimalNumberBehaviors></ref>
protocol.)
</desc>
</method>
<method type="id" factory="yes" ovadd="10.0.0">
<sel>defaultDecimalNumberHandler</sel>
<desc>
Provides an instance implementing the default
behavior for the
<ref type="class" id="NSDecimalNumber">NSDecimalNumber</ref>
class. 38 decimal digits, rounded to closest
return value (<code>NSRoundPlain</code>).
Exceptions raised on overflow, underflow, and
divide by zero.
</desc>
</method>
<method type="id" ovadd="10.0.0">
<sel>initWithRoundingMode:</sel>
<arg type="NSRoundingMode">roundingMode</arg>
<sel>scale:</sel>
<arg type="short">scale</arg>
<sel>raiseOnExactness:</sel>
<arg type="BOOL">raiseOnExactness</arg>
<sel>raiseOnOverflow:</sel>
<arg type="BOOL">raiseOnOverflow</arg>
<sel>raiseOnUnderflow:</sel>
<arg type="BOOL">raiseOnUnderflow</arg>
<sel>raiseOnDivideByZero:</sel>
<arg type="BOOL">raiseOnDivideByZero</arg>
<desc>
Initializer setting all behavior. (For more
precise control over error handling, create your
own class implementing the
<ref type="protocol" id="(NSDecimalNumberBehaviors)"><NSDecimalNumberBehaviors></ref>
protocol.)
</desc>
</method>
</class>
</chapter>
<chapter>
<heading>
Software documentation for the
NSNumber(NSDecimalNumber) category
</heading>
<category name="NSDecimalNumber" class="NSNumber" ovadd="10.0.0">
<declared>Foundation/NSDecimalNumber.h</declared>
<desc>
Interface for obtaining an NSDecimalNumber value
from an ordinary NSNumber.
</desc>
<method type="NSDecimal" ovadd="10.0.0">
<sel>decimalValue</sel>
<desc>
Obtaining an NSDecimalNumber version of an
ordinary NSNumber. <br /> Returns an NSDecimal
representation of the number. Float and
<strong>double</strong> values may not be
converted exactly
</desc>
</method>
</category>
</chapter>
<chapter>
<heading>
Software documentation for the
NSDecimalNumberBehaviors protocol
</heading>
<protocol name="NSDecimalNumberBehaviors" ovadd="10.0.0">
<declared>Foundation/NSDecimalNumber.h</declared>
<desc>
This protocol encapsulates information about how an
<ref type="class" id="NSDecimalNumber">NSDecimalNumber</ref>
should round and process exceptions. Usually you can
just create objects of the
<ref type="class" id="NSDecimalNumberHandler">NSDecimalNumberHandler</ref>
class, which implements this protocol, but if you
don't want to use that class you can create your
own implementing it.
</desc>
<method type="NSDecimalNumber*" ovadd="10.0.0">
<sel>exceptionDuringOperation:</sel>
<arg type="SEL">method</arg>
<sel>error:</sel>
<arg type="NSCalculationError">error</arg>
<sel>leftOperand:</sel>
<arg type="NSDecimalNumber*">leftOperand</arg>
<sel>rightOperand:</sel>
<arg type="NSDecimalNumber*">rightOperand</arg>
<desc>
<p>
Specifies behavior when, in the course of
applying <var>method</var> to
<var>leftOperand</var> and <var>rightOperand</var>,
an
<ref type="class" id="NSDecimalNumber">NSDecimalNumber</ref>instance encounters given <var>error</var>.</p>
<p>
<var>error</var> has four possible constant
values:
</p>
<deflist>
<term>
<code>NSCalculationLossOfPrecision</code>
</term>
<desc>
The number can't be represented in 38 significant
digits.
</desc>
<term><code>NSCalculationOverflow</code></term>
<desc>
The number is too large to represent.
</desc>
<term><code>NSCalculationUnderflow</code></term>
<desc>
The number is too small to represent.
</desc>
<term>
<code>NSCalculationDivideByZero</code>
</term>
<desc>The caller tried to divide by 0.</desc>
</deflist>
<p>
Behavior on <var>error</var> can be one of the
following:
</p>
<list>
<item>Raise an exception.</item>
<item>
Return <code>nil</code>. The calling
<var>method</var> will return its value as
though no <var>error</var> had occurred. If
<var>error</var> is
<code>NSCalculationLossOfPrecision</code>,
<var>method</var> will return an imprecise
value, constrained to 38 significant digits.
If <var>error</var> is
<code>NSCalculationUnderflow</code> or
<code>NSCalculationOverflow</code>,
<var>method</var> will return
<code>NSDecimalNumber</code> 's
<code>notANumber</code>. You shouldn't return
<code>nil</code> if <var>error</var> is
<code>NSDivideByZero</code>.
</item>
<item>
Correct the <var>error</var> and return a
valid <code>NSDecimalNumber</code>. The calling
<var>method</var> will use this as its own
return value.
</item>
</list>
</desc>
</method>
<method type="NSRoundingMode" ovadd="10.0.0">
<sel>roundingMode</sel>
<desc>
Specifies how
<ref type="class" id="NSDecimalNumber">NSDecimalNumber</ref>
's <code>decimalNumberBy...</code> methods round their
return values. This should be set to one of the
following constants:
<deflist>
<term><code>NSRoundDown</code></term>
<desc>Always round down.</desc>
<term><code>NSRoundUp</code></term>
<desc>Always round up.</desc>
<term><code>NSRoundPlain</code></term>
<desc>
Round to the closest possible return value.
Halfway (e.g..5) rounds up for positive
numbers, down for negative (towards larger
absolute value).
</desc>
<term><code>NSRoundBankers</code></term>
<desc>
Round to the closest possible return value, but
halfway (e.g..5) rounds towards possibility
whose last digit is even.
</desc>
</deflist>
</desc>
</method>
<method type="short" ovadd="10.0.0">
<sel>scale</sel>
<desc>
Specifies the precision of the values returned by
<ref type="class" id="NSDecimalNumber">NSDecimalNumber</ref>
's <code>decimalNumberBy...</code> methods, in terms
of the number of digits allowed after the decimal
point. This can be negative, implying that the
precision should be, e.g., 100's, 1000's, etc..
For unlimited precision, set to
<code>NSDecimalNoScale</code>.
</desc>
</method>
</protocol>
</chapter>
</body>
</gsdoc>
|