RPN Calc Contents
RPN Calculator

The Reverse-Polish-Notation calculator for Windows!

All calculations are done in 80-bit, long double floating point arithmetic.

If you would like help on a particular key, press the help [?] key followed by the key inquestion.

Written by:

David Johnston

28022 NE 147th Place

Duvall, WA  98019

How to use RPN

Functions by Name

If you really like this calculator and find it useful, I accept donations.  So let your conscience be yourguide.


Using RPN
Reverse Polish Notation (RPN)

To do normal, everyday calculations, do the following:

- Enter the first operand (type your first number)

- Press the Enter ([Enter] will be abbreviated [#] for discussion)

- Enter the second operand

- Press the function key (*, /, -, +, y^x, xrty...)

For Single operand operations, do this:

- Enter the operand (type your number)

- Press the function key (1/x, sin, cos, x^2, Frac...)

To do Complex operations (nested arithmetic), do this:

- Example 1:	7 * (4 + 5)

  Type: [7] [#] [4] [#] [5] [+] [*]

- Example 2:	(-9 + sqrt( (-9)^2 - 4*2*5)  )/(2*2)

  Type: [9] [+/-] [#] [x^2] [4] [#] [2] [*] [5] [*] [-] [sqrt] [+] [2] [#] [2] [*] [/]

- Example 3:	e^sin ( 45 )

  Type: [Deg] [4] [5] [sin] [e^x]

Every time you press the [Enter] key, data in all the registers is shifted down one.  Thus, theold value in the X register is placed in the Y register, and the X register keeps its value,but you can type a new value in its place.


Asnh Key
Inverse Hyperbolic Sine

[Asnh]

Computes the inverse hyperbolic Sine.

See Also [Sinh]


Acsh Key
Inverse Hyperbolic Cosine

[Acsh]

Computes the inverse hyperbolic cosine.

See Also [Cosh]


Atnh Key
Inverse Hyperbolic Tangent

[Atnh]

Computes the inverse hyperbolic tangent.

See Also [Tanh]


Last X Key
Last X

 [ [image]]

Returns the last value that was in the X register.


GCF Key
Greatest Common Factor

[GCF]

Computes the greates common facter between the numbers in the X and Y registers.

The greates common factor is the largest whole number that will go into both of the givennumbers evenly, without remainders.


Prime Number Key
Next Prime Number

[Pri]

Returns the next prime number greater than, or equal to the value in the X register.

A prime number is a number that has, as its only factors, 1 and the number itself.  No othernumber will divide evenly into a prime number.


Factorial Key
Factorial

[ [image]]

Computes the factorial of the value in the X register.  The factorial is computed by taking theproduct over all whole numbers less than or equal to the given value.  For example, 4! wouldcompute to 1*2*3*4 = 24.


Combinations Key
Combinations

[nCr]

Returns the number of combinations of X items there are in a set of Y items.  For example, ourLotto lets us pick 6 numbers out of 44.  To calculate the chances of winning, type: 44 [Enter]6 [nCr]  for a result of 7,059,052, or about 7 million to one of me winning the Lotto.


Permutations Key
Permutations

[nPr]

Returns the number of combinations of X items from a set of Y items, with the order being pickedimportant.  For example, the odds of me picking the numbers 1, 2, and then 3 in that orderfrom a hat with 10 numbers in it, would be (10 [Enter] 3 [nPr]) one in 720 (not very good).


Random Key
Random

[Ran]

Generate a random number between 0 and 1.


Store Key
Store

[Sto]

Store the value in the X register into one of the 16 storage registers, labeled 0through 9, and A through F.

Data can be cumulatively summed, differenced, multiplied, or divided by numbers in the registers.  In otherwords, if you wish to increase the number in storage register 5 by 900, you wouldtype:  900 [Sto] [+] [5]


Recall Key
Recall

[Rcl]

Copy the contents of one of the 16 storage registers to the X register.


Abs Key
Absolute Value

[Abs]

Take the absolute value of the X register.

The absolute value of a number is the positive of that number.  Positive numbers areleft unchanged, while negative numbers are made positive.


Rect to Polar Key
Rectangular to Polar Conversion

[ [image]]

Place the x and y values of your rectangular coordinates in the X and Y registers respectively,and press the [ [image]] key.  The resultant magnitude of the polar coordinate will bein the X register, and the angle, theta, will be in the Y register.

See Also:  [ [image]]


Polar to Rect Key
Polar to Rectangular Conversion

[ [image]]

Place the angle, theta, into the Y register, and the magnitude of the polar coordinate into theX register and press [ [image]] key.  The resultant x and y values in rectangularcoordinates will be in the X and Y registers respectively.

See Also:  [ [image]]


lnyx Key
Logarithm base Y of X

[ [image]]

Log base y of x.


Fibonacci Key
Fibonacci Constant

[ [image]]

Places the value of the fibonacci constant (1.618033...) into the X register.


MOD Key
Modulus

[MOD]

Take the modulus of a number.  Place the value you wish to modulate in the Y register,and the Modulus in the X register.  For example, 17 MOD 5 is 2, since 17 divided by 5 hasa remainder of 2.  You would type 17 [Enter] 5 [MOD] to get this result.


Rotate Up Key
Roll Up

[ [image]]

Rotate registers up.


Rotate Down Key
Roll Down

[ [image]]

Rotate registers down.


Clear Key
Clear

[C]

Clear the X register.  Same as Clear on normal calculators.  Your other registers remain unchanged.


Numeric Keys

[0] [1] [2] [3] [4] [5] [6] [7] [8] [9] [0] [+/-] [EEX] [.]

The numeric keys, along with a few special keys, are used for entering numbers.

Decimal values can be entered by using the decimal [.] key.

While entering a number, you can make the number negative by pressing the change sign [+/-] key.

Exponenential notation can be entered using the enter exponent [EEX] key.  Pressing the change sign [+/-] keywhile entering the exponent will change the sign of the exponent, not the entire number.


Hexadecimal Keys

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

The letter keys are used to aid in entering hexadecimal [Hex] (base 16) numbers.  You can also use the keyboard keys A through Fwhen entering hexadecimal numbers as well.

The letter keys can also be used as registers for storing [Sto] values along with the numeric keys.


Exchange Key
Exchange X and Y Registers

[ [image]]

Use this function if you wish to use a function that requires both X and Y inputs, and theyare currently reversed from the way you need them to operate the function properly.


Convert to Days Key
Convert from Date to Days

[ [image]]

Enter date, as 7 or 8 digits as [M]MDDYY, and press the [->Dy] key.  For example,  February 16th, 1967 would be entered as21667, while December 30, 1969 would be entered as 123069.  If you enter a year, other than a 19xx year, enter thefull year.  For example, June 7th, 1882, would be entered as 6071882.

The number of days since January 1, 0000 will be displayed (of course, we did not have this calendar for that long,but it's just where the days start from).

This function is handy for calculating the number of days between events.  For example, to find out how old you werein days on August 17, 1987, if you were born on February 29, 1964, you would type:  81787 [->Dy] 22964 [->Dy] [-]

If you wanted to find out what day you turned 10,000 days old, you would type:  22964 [->Dy] 10000 [+] [->Dt]

See Also:  [ [image]]


Convert to Date Key
Convert from Days to Date

[ [image]]

This function returns the date, given the number of days since January 1, 0000.

It is used to convert back dates that were converted to days using the [->Dy] key.

The value returned is in the format [M]MDDYY for dates in the 1900's, and as [M]MDDYYYY for dates that are notin the 1900's.

For example, if the date returned was 40588 then it would be read as April 5, 1988.

See Also:  [ [image]]


Bio Key
Biorhythms

[Bio]

Enter your birthdate, as 7 or 8 digits as [M]MDDYY, and press the [Bio] key.  For example,  February 16th, 1967 would be entered as21667, while December 30, 1969 would be entered as 123069.  The date on your PC is used as the current date forwhich you are checking your biorhythms.

There are 3 rhythms charted:  [P]hysical, [S]ensitivity (emotional), and [I]ntellectual.

Critical days are values close to zero, while semi-critical days are values close to +100 and -100.  Positive values indicate agood physical health, good emotions, and good intellectual stuff, while negative values are the opposite.

If the cycle is going up (or getting better), a caret (^) is placed by the number.  If the cycle is on a downswing,a (d) is placed by the number.

After the calculation, you age in days is in the X register (although you can't see it immediately since thebiorhythm chart is being displayed).


Off Key

[Off]

This turns off the calculator, which is the same as exiting the application.  All registers and valuesare saved.


HEX Key
Hexadecimal (base 16) mode

[HEX]

Change to a base 16 calculator.  Once pressed, all numeric entry, and display of numbers is in hexadecimal, or base 16 notation.In base 16, each digit can be one of 16 values, instead of one of 10 as in decimal notation.  Because we don't have anydigits above '9', the letters 'A' through 'F' are used to represent 10 through 15.  Thus, the number 'C' is12 in decimal.  The number '10' in hexadecimal is '16' in decimal, and so on.

Base 16 is very useful in computer science and electrical engineering, since each digit represents exactly4 binary digits, or bits.  One can look at the hexadecimal number and see the binary number instantly by usingthis table:

Hex	Binary	Decimal

0	0 0 0 0	(0)

1	0 0 0 1	(1)

2	0 0 1 0	(2)

3	0 0 1 1	(3)

4	0 1 0 0	(4)

5	0 1 0 1	(5)

6	0 1 1 0	(6)

7	0 1 1 1	(7)

8	1 0 0 0	(8)

9	1 0 0 1	(9)

A	1 0 1 0	(10)

B	1 0 1 1	(11)

C	1 1 0 0	(12)

D	1 1 0 1	(13)

E	1 1 1 0	(14)

F	1 1 1 1	(15)

See also: [dec], [Tim], [Bin],[b26], [base].


Dec Key
Decimal (base 10) mode

[Dec]

This is the old standard notation we are all used to.

See also: [Hex], [Tim], [Bin],[b26], [base].


Tim Key
Time (base 60) mode

[Tim]

Use the Time mode to calculate times in hours, minutes, seconds, and decimal fractions of a second.  The actual value stored is always in seconds, so you can add, subtract, multiply, or do any operation you wish, and get the proper results.  Remember that ALL numbers are displayed in base 60, so multiplying 1:00 (a minute) by 1:00 (a minute) will give you 1:00:00 (an hour), since 60 times 1 minute equals one hour.

There are many ways to represent the seconds.  In this calculator, they are represented in decimal form.  So 1:05.25 is one minute, and 5.25 seconds.  Other methods divide the second into 30ths (frames), or 60ths.

See also: [Hex], [Dec], [Bin],[b26], [base].


Bin Key
Binary (base 2) mode

[Bin]

Binary notation is used in programming, for example, to represent flags.  Ones are where a flagis set, and zero where a flag is cleared.

See also: [Hex], [Tim], [Dec],[b26], [base].


Base 26 Key
Base 26 mode

[b26]

This is just a fun button.  Only letters of the alphabet are allowed to be typed in.  'A' gets avalue of zero, 'B' a value of one, and so on, up to 'Z' getting a value of twenty-five.

This may be handy for writing secret codes???

See also: [Hex], [Tim], [Bin],[dec], [base].


Base Key
Base x mode

[base]

Set the entire calculator, both input data entry, and output display to any number base youwish.  Normally, we think of numbers in base 10, but that's just an arbitrary number, probablydecided on since we have 10 fingers I guess.

See also: [Hex], [Tim], [Bin],[b26], [dec].


Int Key
Integer

[Int]

Convert the value in the X register to an interger.

See Also: [Frac].


Frac Key
Fraction

[Frac]

Keep only the fractional part of the number in the X register.

See Also: [Int].


Multiply Key
Multiply

[ [image]]

Multiply two numbers together.  For example, 6 time 7 would be typed in as:  6 [Enter] 7 [ [image]].


Divide Key
Divide

[ [image]]

Divide the number in the Y register by the number in the X register.  For example, to divide 50by 10, you would type:  50 [Enter] 10 [ [image]]


Addition Key
Add

[+]

Add the numbers in the X and Y registers, and place the result in the X register.  For example,to add 5 and 13, you would type 5 [Enter] 13 [+]


Subtraction Key
Subtract

[-]

Subtract the number in the X register from the number in the Y register.  For example, to subtract19 from 100, you would type 100 [Enter] 19 [-]


Enter Key
Enter

This is the key that makes RPN calculators different from the other kind (the kind with an equalskey).  Pressing [Enter] will shift all the data down by one register.


Pi Key
Pi

[Pi]

This key places the value of pi (3.1415926535...) into the x register, as if you typed it.

Pi is the ratio between the diameter and circumference of a circle.  The Circumference of any sized circledivided by its diameter will always give the value pi.

It can be calculated in several ways.  One way is by the series 1 - 1/3 + 1/5 - 1/7 + 1/9 - 1/11 and so on,multiplied by 4 (since the series gives pi/4).  The way the RPN Calculator calculates pi is by taking four timesthe inverse tangent [Atan] of one.  There is a series for calculating inverse tangentsas well, but I forget what it is.

Incedentally, pi is pronounced 'pie', not 'pee', or 'pih'.


e Key
e

[ [image]]

This key places the value of the natural number [image] (2.71828182...) into the x register, as if you typed it.


Backspace Key
Backspace

[ [image]]

This is identical to pressing the Backspace key.  Use this key if you make a mistake while typingin a number.


Fix Key
Fix number of decimal places

[Fix]

Sets the number of decimal places to the value in the X register, and displays in standarddecimal notation.  For example, if you were working with dollar figures, you would want tohave numbers with 2 decimal places.  You would type:  [2] [Fix]

See also:  [Sci], [Eng]


Sci Key
Scientific Notation

[Sci]

Sets the number of decimal places to the value in the X register, and displays all numbersin scientific notation.  For example, to have all numbers with 3 digit precision, you wouldtype:  [3] [Sci]

See also:  [Fix], [Eng]


Eng Key
Engineering Notation

[Eng]

Engineering notation is similiar to scientific notation, except that the powers of 10 (orwhatever base you are using) are always a multiple of three.  This way, it is easy to seeif the number is in the millions, billions, or whatever.

See also:  [Sci], [Fix]


Ln Key
Natural Logarithm

[ln]

The inverse of e [ [image]] raised to the x [ [image]].


Exp Key
Power of e

[ [image]]

The inverse of natural log [ln].


Sin Key
Sine trigonometric function

[Sin]

Modes can be changed between radians [Rad], degrees [Deg],and grads [Grad].

See also: [Asin]


Cos Key
Cosine trigonometric function

[Cos]

Modes can be changed between radians [Rad], degrees [Deg],and grads [Grad].

See also: [Acos]


Tan Key
Tangent trigonometric function

[Tan]

Modes can be changed between radians [Rad], degrees [Deg],and grads [Grad].

See also: [Atan]


Asin Key
Inverse Sine trigonometric function

[Asin]

Modes can be changed between radians [Rad], degrees [Deg],and grads [Grad].

See also: [Sin]


Acos Key
Inverse Cosine trigonometric function

[Acos]

Modes can be changed between radians [Rad], degrees [Deg],and grads [Grad].

See also: [Cos]


Atan Key
Inverse Tangent trigonometric function

[Atan]

Modes can be changed between radians [Rad], degrees [Deg],and grads [Grad].

See also: [Tan]


Sinh Key
Hyperbolic Sine function

[Sinh]


Cosh Key
Hyperbolic Cosine function

[Cosh]


Tanh Key
Hyperbolic Tangent function

[Tanh]


Log Key
Logarithm, base 10

[log]

This is the inverse of 10 raised to the x [ [image]].


Power of 10 Key
Power of 10

[ [image]]

This is the inverse of the logarithm base 10 [log].


Reciprocol Key
Recriprocol

[ [image]]

This key quickly takes one over your value.  For example, if you typed [5] [1/x], the result would be 0.2


Square Key
Square

[{x2.bmp}]

This key quickly gives you the square of the x register.  For example, typing [5] [x^2] will result in 25

The square is found by multiplying X by itself, or raising it to a power of two.

The inverse of the square function is the square root [sqrt].

Squares are never negative, (unless imaginary numbers are squared), since multiplying a negative number by it self(another negative number) results in a positive number.


Square Root Key
Square Root

[ [image]]

This key quickly gives you the square root of the x register.  For example, typing [16] [sqrt] will result in 4

The result found, when multiplied by it self, will equal the original number, as in 4 * 4 = 16.

The inverse of the square root function is the square function [x^2].

Square roots often result in irrational numbers.


Power Key
Y to the power of X

[ [image]]

The inverse of this function is the x-th root of y [xrty], which is identical to raisingY to the power of 1/X.


Power Inverse Key
X-th root of Y

[ [image]]

The inverse of this function is the power key [y^x].


Degrees Key
Degrees mode

[Deg]

See also: [Sin], [Cos], [Tan],[Asin], [Acos], [Atan].


Radians Key
Radians mode

[Rad]

See also: [Sin], [Cos], [Tan],[Asin], [Acos], [Atan].


Grads Key
Grads mode

[Grad]

See also: [Sin], [Cos], [Tan],[Asin], [Acos], [Atan].


Functions by Name

Calculator control

[Off]	Turn off Calculator

Trigonometric modes

[Rad]	Radians mode

[Grad]	Grads mode

[Deg]	Degrees mode

Display modes

[Fix]	Fix decimal places

[Sci]	Fix decimal places, scientific notation

[Eng]	Fix decimal places, engineering notation

Numeric bases

[b26]	Base 26 (alphabetical) mode

[HEX]	Base 16 (hexadecimal) mode

[DEC]	Base 10 (decimal) mode

[Tim]	Base 60 (time) mode

[BIN]	Base 2 (binary) mode

[Base]	Base x mode (maximum = 36)

Data entry keys

[EEX]	The Enter EXponent

[+/-]	Change sign

[<-]	Backspace

Standard arithmetic

[*]	Multiply

[/]	Divide

[+]	Add

[-]	Subtract

Constants, and one non-constant

[Pi]	Enter pi, 3.1415...

[e]	Enter e, 2.71828...

[f]	Enter fibonacci number, 1.618...

[Ran]	Random number

Stack keys

[Enter]	Enter key

[X=Y]	Exchange X and Y

[Rup]	Roll Up.

[Rdn]	Roll Down.

[Lstx]	Last X.

[C]	Clear X register

Logarithms and Powers

[10^x]	10 to the power of X

[log]	Logarithm base 10

[e^x]	Raise e to the power of X

[ln]	Logarithm base e

[y^x]	Raise Y to the power of X

[lnyx]	Logarithm base y of x

[xrty]	X-th root of Y

Number portion and Modulus

[MOD]	Modulus

[Int]	Integer portion

[Frac]	Fractional portion

Conversions

[->P]	Rectangular to Polar conversion

[->R]	Polar to Rectangular conversion

Unary operators

[Abs]	Absolute Value

[1/x]	Reciprocol

[x^2]	Square

[sqrt]	Square Root

Memory storage

[Sto]	Store

[Rcl]	Recall

Probability

[nCr]	Combinations.

[nPr]	Permutations.

[x!]	Factorial.

Prime Numbers and Factoring

[Pri]	Next Prime Number.

[GCF]	Greatest Common Factor.

Trigonometric functions

[sin]	Trigonometric sine

[Asin]	Inverse trigonometric sine

[cos]	Trigonometric cosine

[Acos]	Inverse trigonometric cosine

[tan]	Trigonometric tangent

[Atan]	Inverse trigonometric tangent

Hyperbolic functions

[sinh]	Hyperbolic sine

[Asnh]	Inverse hyperbolic sine

[cosh]	Hyperbolic cosine

[Acsh]	Inverse hyperbolic cosine

[tanh]	Hyperbolic tangent

[Atnh]	Inverse hyperbolic tangent

Date functions

[->Date]	Convert to Date

[->Day]	Convert to Days

[Bio]	Biorhythm