1 ReactOS Calc is a programme for evaluating mathematical, financial and statistical calculations.

3 ReactOS Calc has several features including:

4 - Internal precision with 17 decimal numbers (standard IEEE math library).

5 - Up to 512 bits of internal precision and 64 decimal digits displayed in the output display (with GNU multi-precision libraries).

6 - Robust RPN (reverse polish notation) engine which allows a virtually unlimited number of arithmetic and algebraic sub-expressions.

7 - Three different interfaces: standard, scientific or conversion.

8 - Many common arithmetic, algebraic and statistical functions are included.

10 The following topics will be discussed:

12 HOW TO INPUT NUMBERS

13 DISPLAY FORMAT

14 ERROR MESSAGE

15 ARITHMETIC FUNCTIONS

16 LOGICAL FUNCTIONS

17 ALGEBRAIC FUNCTIONS

18 TRIGONOMETRIC FUNCTIONS

19 THE PI BUTTON

20 HYPERBOLIC FUNCTIONS

21 STATISTICAL FUNCTIONS

22 MEMORY FUNCTION

23 DEGREE CONVERSION

24 FIXED SCIENTIFIC NOTATION

25 PERCENT MODE

27 HOW TO INPUT NUMBERS

28 --------------------

29 The ReactOS Calc provides some buttons for typing numbers and expressions.

30 However, some of them are available only into Standard, Conversion or Scientific modes, or when the calculator is in a specific state.

31 [0], [1], [2], [3], [4], [5], [6], [7], [8], [9]

32 Digit buttons: they are used for entering digits into the display.

33 [A], [B], [C], [D], [E], [F]

34 Hexadecimal buttons: they are used for completing an hex number. For using these buttons, the calculator must be configured into scientific mode and the [HEX] state must be selected.

35 [.] or [,]

36 Decimal point: used for starting the non integer part of a decimal number.

37 [+/-]

38 Change sign: if it's pressed after a calculation or when entering the operands, it will change the sign of the number shown into the output display.

39 [BACK]

40 If the displayed number has been entered manually and it isn't a result of a calculation, you can delete the last digit by pressing this button.

41 [CE]

42 This button removes an incorrect number from the output display. All pending operations are preserved.

43 [ C ]

44 It clears the output display and all pending operations.

46 DISPLAY FORMAT

47 --------------

48 You can enter digits by pressing the buttons mentioned in the <HOW TO INPUT NUMBERS> section.

49 These numbers can be entered into four different bases: hexadecimal, decimal, octal or binary system.

50 A number shown into the output display can be easily converted from a numeric base to another by simply changing the base on the fly.

52 When working with pure decimal numbers, the user can enter the numbers in two ways:

53 - Normal mode: each number is entered its integer part and, eventually, its fractional part.

54 - Exponential mode: the number is entered by typing a mantissa and then an exponent. This method allows you to write very big or very small numbers that you would not be able to type in a different manner. You can use it only when the calculator is configured in scientific mode.

55 However, there are some limits even when you work with exponential notation.

56 These limits are:

57 -1.79769313486231570e+308 <= x <= -2.22507385850720140e-308

58 2.22507385850720140e-308 <= x <= 1.79769313486231570e+308

59 The exponential input mode is activated by the [Exp] button.

60 After the mantissa has been typed, by pressing this button you will be able to enter the exponent.

61 When the support for GNU multi-precision libraries is activated, these limits rise greatly to 64 displayed digits for the mantissa and 8 digits for the exponent, both with sign.

63 When the calculator is in [HEX], [OCT] or [BIN] state, it's possible to apply a masking for limiting the range of the numbers. Four range are available:

64 [QWORD]

65 It limits the integers to 64 bit numbers.

66 [DWORD]

67 It limits the integers to 32 bit numbers.

68 [WORD]

69 It limits the integers to 16 bit numbers.

70 [BYTE]

71 It limits the integers to 8 bit numbers.

73 ERROR MESSAGE

74 -------------

75 The output display will show the message "Error" if the current calculation overflows the limits of the calculator, or when an undefined condition is generated (example: division by zero).

76 The error condition is cleared using the [ C ] button.

78 ARITHMETIC FUNCTIONS

79 --------------------

80 ReactOS Calc implements the standard arithmetic rules with the following operators:

81 [+]

82 Addition

83 [-]

84 Subtraction

85 [*]

86 Multiplication

87 [/]

88 Division

89 [Mod]

90 Remainder of a division

91 Those rules express the concept of priority.

92 Here there is a list of priorities implemented from the highest to the lowest:

93 - Special functions which change directly the current value into a new one: trigonometrics, hyperbolics, exponentials and logarithms, reciprocal, base conversions, integer and fractional part detection and change of sign.

94 - Power and root functions.

95 - multiplications, divisions, reminders.

96 - additions, subtractions.

97 - Logical functions.

98 These rules may be overcome by using parentheses.

99 With [(] and [)] buttons, the user can isolate a mathematical expression to be evaluated separately. The number of parentheses into a single expression is virtually unlimited. The number of currently-open parentheses is displayed in the left box underneath the base change option set.

101 LOGICAL FUNCTIONS

102 -----------------

103 There is a set of logical functions which can be used between two operands. They can be used as normal arithmetic operators.

104 The only exception is the "Not" operator which works on a single number.

105 The provided functions are:

106 [And]

107 It executes an "and" between the numbers.

108 [Or]

109 It executes an "or" between the numbers.

110 [Xor]

111 It executes an "exclusive or" between the numbers.

112 [Not]

113 It inverts all bits of the number shown into the output display.

115 ALGEBRAIC FUNCTIONS

116 -------------------

117 ReactOS Calc implements the most commonly used algebraic functions.

118 [Int]

119 It isolates the integer part of the number shown into the output display.

120 [Inv]+[Int]

121 The integer part of the number is discarded and the fractional part stays on the output display.

122 [x^2]

123 Square function. It calculates the square of the number shown on the output display.

124 [Inv]+[x^2]

125 It returns the positive square root of the number shown on the output display.

126 If the current number is negative, then the error message will be displayed.

127 When working with standard and conversion layouts, the [sqrt] button is a shortcut to this function.

128 [x^3]

129 Cube function. It calculates the cube of the number shown on the output display.

130 [Inv]+[x^3]

131 It returns the cube root of the number shown on the output display.

132 [x^y]

133 Power function. It calculates the power of X elevated to Y.

134 [Inv]+[x^y]

135 Root function. It calculates the Y-th root of X.

136 [1/x]

137 Reciprocal. It divides 1 by the number shown on the output display.

138 [n!]

139 Factorial. It calculates the factorial of the integer part of the number shown into the output display.

140 The calculation is defined within these limits:

141 0 <= n <= 170

142 [ln]

143 Natural logarithm. It calculates the natural logarithm of the current number.

144 ReactOS Calc assumes the Nepero's constant to be:

145 e=2.7182818284590452354

146 The calculation is defined for x > 0.

147 [Inv]+[ln]

148 Natural anti-logarithm. It calculates the power of the Nepero's constant to the current number.

149 [Log]

150 Decimal logarithm. It calculates the logarithm of the current number to base 10.

151 The calculation is defined for x > 0.

152 [Inv]+[Log]

153 Decimal anti-logarithm. It calculates the power of 10 to the current number.

155 TRIGONOMETRIC FUNCTIONS

156 -----------------------

157 ReactOS Calc allows the calculation of three types of trigonometric functions with their inverse operations.

158 These functions can be used with three different angular units of measurement: degrees, radians or gradians.

159 The angular mode does not affect the non trigonometric functions.

160 Please note that the degree type uses decimal degrees and not angles in the degree-minute-second form.

161 The available functions are:

162 [sin]

163 It calculates the sine of the given angle.

164 If the [Inv] modifier is activated, it finds the angle whose sine value is shown into the output display.

165 [cos]

166 It calculates the cosine of the given angle.

167 If the [Inv] modifier is activated, it finds the angle whose cosine value is shown into the output display.

168 [tan]

169 It calculates the tangent of the given angle.

170 If the [Inv] modifier is activated, it finds the angle whose tangent value is shown into the output display.

172 THE PI BUTTON

173 -------------

174 For helping the calculations with trigonometric functions, it's possible to load the value of 'Pi' into the output display.

175 The function is called by pressing the [PI] button.

176 If the [Inv] modifier is activated, then the output display will be loaded with 2*PI.

177 In ReactOS Calc, Pi has the value 3.14159265358979323846

179 HYPERBOLIC FUNCTIONS

180 --------------------

181 ReactOS Calc allows the calculation of three types of hyperbolic functions with their inverse operations.

182 Those functions are activated by the same buttons used for trigonometric functions; the hyperbolic context is enabled by activating the [Hyp] modifier. The inverse functions are activated by the [Inv] modifier.

183 [sin]+[Hyp]

184 Hyperbolic sine

185 [cos]+[Hyp]

186 Hyperbolic cosine

187 [tan]+[Hyp]

188 Hyperbolic tangent

190 STATISTICAL FUNCTIONS

191 ---------------------

192 By pressing the [STA] button, the statistical window is enabled.

193 Statistical window allows to store groups of number and execute some common statistical operators.

194 Into the statistical box, there are four buttons with these functions:

195 [RET]

196 It moves the focus back to the calculator.

197 [LOAD]

198 It loads the selected number into the output display of the calculator.

199 [CD]

200 It deletes the selected number from the list.

201 [CAD]

202 It deletes all numbers currently stored into the list.

204 While the statistical window is shown, four additional buttons are enabled:

205 [Ave]

206 It calculates the arithmetic average of the numbers stored into the list.

207 [Sum]

208 It calculates the sum of all numbers stored into the list.

209 [s]

210 It calculates the population standard deviations of the numbers stored into the list.

211 [Dat]

212 It inserts the number shown into the output display into the list.

214 Note: when the statistical box is closed, its content is lost.

216 MEMORY FUNCTION

217 ---------------

218 ReactOS Calc reserves for the user a memory region for storing data.

219 With this feature, the user can store frequently used numbers (typically, these numbers are constants) and recall them at any time, without the need to re-enter them manually.

220 If the memory function is currently in use, the text "M" will appear in the right box underneath the base change option set.

221 The memory is preserved when switching between standard, conversion and scientific modes, but its content is lost when ReactOS Calc application is closed.

222 Four keys are available with memory function support.

223 [MC]

224 Memory Clear: clears the content of the memory.

225 [MR]

226 Memory Recall: retrieves the stored data from the memory and it shows it into the output display, without affecting the content of the storage.

227 [MS]

228 Memory Store: stores the displayed value into the memory. The content of the display is unaffected. After pressing this button, the previous content of the memory is lost. If the [INV] modifier is activated, then this button will swap current memory value with displayed value. Under these conditions, the displayed value is stored and the previously stored quantity is shown on the output display.

229 If the memory is empty, it will act as a normal store.

230 [M+]

231 Memory Sum: the displayed value is algebraically added to the current memory. The output display will be unchanged after this transfer and addition. If the [INV] modifier is activated, then the displayed value will be algebraically subtracted from the memory. If the memory is empty, it will work in both condition as a simple memory store.

233 DEGREE CONVERSION

234 -----------------

235 With [dms] button you can convert decimal degrees into degree-minute-second format and vice-versa.

236 When working with d-m-s angles, the notation used into the output display is "DDD.MMSS" where D stands for degree, M for minute and S for second.

237 The [dms] button will convert decimal angles to degree-minute-second angles.

238 The [dms] button with [Inv] modifier will convert degree-minute-second angles into decimal angles.

240 FIXED SCIENTIFIC NOTATION

241 -------------------------

242 When working with ReactOS Calc, it is possible to select a temporary scientific notation (activated by [Exp] button) or a fixed scientific notation.

243 Fixed scientific notation will be turned on by pressing [F-E] button.

244 When fixed scientific notation is active, all results will be displayed with scientific notation even for small numbers.

245 The calculator will be restored to normal mode by pressing [F-E] button again or by pressing the [ C ] button.

247 PERCENT

248 -------

249 The [%] button is available only with standard and conversion layouts and it's used as modifier for the four basic arithmetic operators.

250 The input sequence for a percent calculation is:

251 "first" "operator" "second" "percent"

252 The modification applied by the percent button for each operator are:

253 [+]

254 Add "second"-% of "first" to "first".

255 [-]

256 Subtract "second"-% of "first" from "first".

257 [*]

258 Multiply "second"-% of "first" with "first".

259 [/]

260 Divide "first" by "second"-% of "first".

262 GLOSSARY

263 --------

265 Output display

266 This is the place where the typed numbers and the results of the calculations are shown.

268 Hex

269 It selects the hexadecimal numeric base and it converts the number shown into the output display.

270 Shortcut from keyboard: F5

272 Dec

273 It selects the decimal numeric base and it converts the number shown into the output display.

274 Shortcut from keyboard: F6

276 Oct

277 It selects the octal numeric base and it converts the number shown into the output display.

278 Shortcut from keyboard: F7

280 Bin

281 It selects the binary numeric base and it converts the number shown into the output display.

282 Shortcut from keyboard: F8

284 Degrees

285 It enables the processing of trigonometric functions into degree format.

286 Shortcut from keyboard: F2

288 Radians

289 It enables the processing of trigonometric functions into radians format.

290 Shortcut from keyboard: F3

292 Gradians

293 It enables the processing of trigonometric functions into gradians format.

294 Shortcut from keyboard: F4

296 Qword

297 It limits the length of integer numbers to 64 bits.

298 Shortcut from keyboard: F12

300 Dword

301 It limits the length of integer numbers to 32 bits.

302 Shortcut from keyboard: F2

304 Word

305 It limits the length of integer numbers to 16 bits.

306 Shortcut from keyboard: F3

308 Byte

309 It limits the length of integer numbers to 8 bits.

310 Shortcut from keyboard: F4

312 Inv

313 It enables the inverse function for [sin] [cos] [tan] [pi] [x^y] [x^2] [x^3] [ln] [log] [dms] [MS] [M+] [Int] buttons.

314 Shortcut from keyboard: I

316 Hyp

317 It enables the hyperbolic mode for [sin] [cos] [tan] buttons

318 Shortcut from keyboard: H

320 Back

321 It deletes the last digit typed on the calculator.

322 It also disables the temporary scientific mode if an exponent is removed completely.

323 Shortcut from keyboard: Backspace

325 CE

326 It deletes the last typed number from the output display.

327 Shortcut from keyboard: Delete

329 _C_

330 It deletes the current calculation and all sub expressions.

331 Shortcut from keyboard: ESC

333 F-E

334 It enables or it disables the fixed scietific notation.

335 Shortcut from keyboard: V

337 0 1 2 3 4 5 6 7 8 9

338 These buttons are used for entering digits.

339 Shortcut from keyboard: the corresponding number on the keyboard or the numeric pad.

341 A B C D E F

342 These buttons are used for entering hexadecimal numbers.

343 Shortcut from keyboard: the letters from A to F.

345 +/-

346 It changes the sign of the number.

347 Shortcut from keyboard: F9

349 . or ,

350 It adds the decimal point for a decimal number.

351 Shortcut from keyboard: , or .

353 +

354 Addition

355 Shortcut from keyboard: +

357 -

358 Subtraction

359 Shortcut from keyboard: -

361 *

362 Multiplication

363 Shortcut from keyboard: *

365 /

366 Division

367 Shortcut from keyboard: /

369 =

370 It resolves the current calculation and all sub expressions.

371 Shortcut from keyboard: =

373 Mod

374 Remainder of an integer division.

375 Shortcut from keyboard: %

377 And

378 Logical "and".

379 Shortcut from keyboard: &

381 Or

382 Logical "or".

383 Shortcut from keyboard: |

385 Xor

386 Logical exclusive "or".

387 Shortcut from keyboard: ^

389 Lsh

390 Logical shift to left.

391 Shortcut from keyboard: <

393 Not

394 Logical bit inversion.

395 Shortcut from keyboard: ~

397 Int

398 It isolates the Integer or fractional part of a number.

399 Shortcut from keyboard: ;

401 MC

402 It deletes the memory.

403 Shortcut from keyboard: CTRL-L

405 MR

406 It recalls a previously stored number from the memory.

407 Shortcut from keyboard: CTRL-R

409 MS

410 It stores a number into the memory and it eventually transfers the previous value to the output display.

411 Shortcut from keyboard: CTRL-M

413 M+

414 It adds or it subtracts the value into the output display to the memory.

415 Shortcut from keyboard: CTRL-P

417 pi

418 It loads the pi or 2*pi value into the output display.

419 Shortcut from keyboard: P

421 (

422 It starts a new sub expression.

423 Shortcut from keyboard: (

425 )

426 It closes and it resolves a sub expression.

427 Shortcut from keyboard: )

429 dms

430 It converts a decimal degree to a decimal-minute-second degree and viceversa.

431 Shortcut from keyboard: M

433 Exp

434 It enables the temporary scientific notation.

435 Shortcut from keyboard: X

437 ln

438 It calculates the natural logarithm. Natural anti logarithm calculation is activated by Inv modifier.

439 Shortcut from keyboard: N

441 Log

442 It calculates the decimal logarithm. Decimal anti logarithm calculation is activated by Inv modifier.

443 Shortcut from keyboard: L

445 n!

446 It calculates the factorial of a number.

447 Shortcut from keyboard: !

449 1/x

450 It calculates the reciprocal of a number.

451 Shortcut from keyboard: R

453 sin

454 It calculates the sine, hyperbolic sine, arcsine or the hyperbolic arcsine of an angle.

455 Shortcut from keyboard: S

457 cos

458 It calculates the cosine, hyperbolic cosine, arcsine or the hyperbolic arccosine of an angle.

459 Shortcut from keyboard: O

461 tan

462 It calculates the tangent, hyperbolic tangent, arcstangent or the hyperbolic arctangent of an angle.

463 Shortcut from keyboard: T

465 x^y

466 It calculates the power of X to Y.

467 With the Inv modifier, it calculates the Yth root of X.

468 Shortcut from keyboard: Y

470 x^2

471 It calculates the square of X.

472 With the Inv modifier, it calculates the square root of X.

473 Shortcut from keyboard: @

475 x^3

476 It calculates the cube of X.

477 With the Inv modifier, it calculates the cubic root of X.

478 Shortcut from keyboard: $

480 Sta

481 It enables the statistical window and its functions.

482 Shortcut from keyboard: CTRL-S

484 Ave

485 It calculates the arithmetic average of the numbers stored into the statistical box.

486 Shortcut from keyboard: CTRL-A

488 Sum

489 It calculates the sum of the numbers stored into the statistical box.

490 Shortcut from keyboard: CTRL-T

492 s

493 It calculates the standard deviation of the numbers stores into the statistical box.

494 Shortcut from keyboard: CTRL-D

496 Dat

497 It inserts a new number into the statistical box

498 Shortcut from keyboard: Insert

500 %

501 It executes the calculation with percent mode.

502 Shortcut from keyboard: %

504 sqrt

505 It calculates the square root of a number.

506 Shortcut from keyboard: @