Friday, July 27, 2018

HP Prime: 3D Graphs July 2018 Gallery


HP Prime:  3D Graphs July 2018 Gallery

All graphs are made with the initial rangers x = [-4, 4], y = [-4, 4], and z = [-4, 4] rotated at different angles.  The function variable for 3D graphs for the HP Prime is FZ# (# is 0-9).  


 z = cos (xy) * cos(2xy) * cos(3xy)

z = e^(-sin(2xy)*cos(xy)/2)

z = cos y * (e^(-x^2/2) – e^(x^2/8))

z = sin(x*y) * cos(x*y) + sin(x*y)^2 * cos(x*y)

z = x^4 * y * cos(x*y) * e^(x*y)

z = ± (x^2 – y^2)

z = ± |sin(x*y) – cos(x*y) + x* e^y| 
z = y^2 * sin x * Γ(x/6)

z = x * sin(|x^2 + y^2|)
Until next time, have a great weekend and see in you August!

Eddie


 All original content copyright, © 2011-2018.  Edward Shore.   Unauthorized use and/or unauthorized distribution for commercial purposes without express and written permission from the author is strictly prohibited.  This blog entry may be distributed for noncommercial purposes, provided that full credit is given to the author.  Please contact the author if you have questions.


Wednesday, July 25, 2018

HP Prime: Firmware Update (13865, date 2018.07.06)


HP Prime:  Firmware Update (13865, date 2018.07.06)




There is a new update to the HP Prime firmware.  The new version is 13865. 

You can find the file and details here:

Details and file: 




I haven’t had much chance to work with the new firmware, however according to the release information, some of the highlights are:

* There is a new red indicator when the HP Prime’s power reaches below 10%.

* All integrals in HOME mode will calculate numerical results.  Previously results are returned in either numerical or exact answers.  Exact answers will still be provided in CAS mode.

* You can control the amount of time until the HP Prime dims its screen.  The screen is dimmed when you do nothing on the calculator after a set amount of time.  The time is set in milliseconds as a base integer (30,000 in decimal or 7530_16 in hexadecimal).  The variable is TDim found in the Vars-Setting menu. 

* The command EVAL is said to now help INPUT with local variables.  I haven’t played around with this yet. 

* Updated CAS and improvements


As a note, there the HP Prime now gets a new processor G2.   To find out what hardware version you have, press [Help], press the soft key (Tree), scroll up, select About HP Prime.  I have hardware revision C.  The threads on the MoHPC site goes into more details.  The reason why I mention this is if you have trouble updating your HP Prime, the firmware files may need to be in a new folder.  The folder is:

Hardware C (and I’m assuming this will work for A):
(your drive) \HP Connectivity Kit\Firmware\PrimeG1

Thank you to HP and HP Museum of Calculators! 

Happy Computing,

Eddie

All original content copyright, © 2011-2018.  Edward Shore.   Unauthorized use and/or unauthorized distribution for commercial purposes without express and written permission from the author is strictly prohibited.  This blog entry may be distributed for noncommercial purposes, provided that full credit is given to the author.  Please contact the author if you have questions.

Monday, July 23, 2018

Algebra: Multiplying a * b Trick (Using the Difference between a and b)


Algebra:  Multiplying a * b Trick (Using the Difference between a and b)

Can we find a formula to find products where two values are an equal-distant apart

The Values of a and b Differ by 2

Let a and b be real numbers which differ by 2, that is b – a = 2.  Here I am assuming that b > a. 

Let n be the midpoint between a and b.  That is:

n = b – 1 and
n = a + 1

Therefore:

b = n + 1
a = n - 1

Then:

a * b
= (n - 1) * (n + 1)
= n^2 - n + n – 1
= n^2 - 1

Example:  51 * 49

Notice that:

51 – 49 = 2, and
51 - 1 = 50
49 + 1 = 50

Hence:

51 * 49 = 50^2 – 1 = 2499

Can we expand this included products of a * b, where the difference is b – a = 2 * w

The Values of a and b Differ by 2*w

Let’s look at a more general case. 

Let b – a = 2*w

Then:

b = n + w and a = n – w

Then:

a * b
= (n – w) * (n + w)
= n^2 – n*w + n*w – w^2
= n^2 – w^2

Example:  37 * 43.

43 – 37 = 6
w = 6/2 = 3
Then:
n = 43 – 3 = 37 + 3 = 40

Then:

37 * 43 = 40^2 – 3^2 = 1600 – 9 = 1591


Try another example:  57 * 49

57 – 49 = 8
8 / 2 = 4
57 – 4 = 53, 49 + 4 = 53

Then:

57 * 49 = 53^2 – 4^2 = 2809 – 16 = 2793


In summary for a * b with b > a.

Let w = (b – a)/2 and n = a + w or n = b – w

Then a * b = n^2 – w^2

Eddie

All original content copyright, © 2011-2018.  Edward Shore.   Unauthorized use and/or unauthorized distribution for commercial purposes without express and written permission from the author is strictly prohibited.  This blog entry may be distributed for noncommercial purposes, provided that full credit is given to the author.  Please contact the author if you have questions.

Wednesday, July 18, 2018

Fun with the FX-603P Emulator


Fun with the FX-603P Emulator





Author for the Emulator:  Martin Krischik



Cost: $5.99 (there is an fx-602P scientific calculator emulator for $4.99, similar programming language but only 10 programming spaces instead of 20)

The app is emulates the 1990 Casio fx-603P calculator.



Decibels to Pressure

Program: (29 steps)

“DB?”  HLT  ÷ 20  = 10^x  *  2E-5  = “Pressure:” HLT

Examples:

DB = 30 dB; Result:  6.32455532 * 10^-4 N/m^2

DB = 120 dB; Result:  20 N/m^2

Turn Performance

Given a plane’s true air speed (TAS in knots), stall speed (in knots), and required bank turn (in degrees), the following are calculated:

1. G force
2.  Normal stall speed for the plane during the turn (knots)
3.  Turn diameter (nautical miles)
4.  Time it takes for the turn to be complete (in minutes)

Formulas:

G = 1/(cos(bank))

Stall speed = normal stall speed * G

Diameter = TAS^2 / (34208 * tan(bank))

Time = (0.0055 * TAS) / tan(bank)

Memory Registers:

Input:

M00 = TAS, M01 = Stall speed, M02 = Bank

Output:

M03 = G force, M04 = resulting stall speed, M05 = diameter, M06 = time

Program: (110 steps)

DEG “TAS?” HLT Min00
 “Norm. Stall?” HLT  Min01
 “Bank?” HLT Min02
MR02 cos 1/x Min03 “G:” HLT
MR03 √ * MR01 = “Stall Speed:” HLT
MR00 x^2 ÷ ( MR02 tan * 34208 ) = Min05 “Diameter:” HLT
0.0055 * MR00 ÷ MR02 tan “Time:” HLT Min06

Notes: 
DEG:  [ MODE ] [ 4 ]


Example:

Inputs:
TAS: 123 knots
Norm. Stall:  60 knots
Bank:  44.8°

Results:
G:  1.409302674
Stall Speed: 71.22843498 knots
Diameter:  0.445363387 n.m.
Time: 0.681239424 minutes (about 40.87 seconds)

Source:  “Turn Performance” HP 65 Aviation Pac-1 Hewlett Packard.  1974
.

Sum of a Function

This program uses the subroutine (under P9 with the variable MinF, or any register M04 or after) to calculate the summation:

Σ f(x) for x = a to b

The sum is stored in M03.

Note: when entering a new f(x), clear P9 (MODE, 3, P9, AC) first before entering the new function.  It’s a lot cleaner.

Main Program:  (34 bytes)

0 Min03
“a?” HLT Min01
“b?” HLT Min02
MR02 – MR01 + 1 = Min00
Lbl0
MR01 GSBP9 M+03
1 M+01
DSZ Goto0
MR03 “Σ=”

Note: 
Lbl0:  [ LBL] [ 0 ]
GSBP9: [GSB] [ P9 ]
Goto0:  [ GOTO ] [ 0 ]
The character Σ:  (in ALPHA) [SHIFT] [ 7 ]
Memory F:  [ Min ], [ MR ], etc.  [EXE] for F.

Examples:

Σ n^2 + 3*n – 6 for n = 1 to 8 
Subroutine:
Min0F x^2 + 3 * MR0F – 6 =

Result:  264

Σ (n^3 – 1)/(n^2 + 1) for n = 0 to 11
Subroutine:
( Min0F x^y 3 – 1 ) /div (MR0F x^2 + 1 ) =

Result: 61.6582396282

Combinations: where Repetition is allowed

The program calculates the number of combinations where repeats are allowed.

nHr = (n + r – 1)! / (r! * (n -1)!)

Program:  (39 steps)

“n?” HLT Min01
“r?” HLT Min02
( MR01 + MR02 – 1) x!
÷ ( MR02 x! * ( MR01 – 1 ) x! )
= “nHr=”

Examples:

Input: n = 5, r = 3.  Result:  35

Input: n = 12, r = 6.  Result:  12376

Aviation:  Rate of Climb

This program calculates the rate-of-climb (ft/min) when plane increases the elevation (in feet) given the distance to the mountain (in nautical miles, n.m.) and the true air speed (TAS, in knots). 

Formula:

ROC = ( TAS * ΔALT  ) / (60 * (dist^2 + (ΔALT/6077.1155)^2) )

Program: (88 steps)

6077.1155 Min0F
“TAS (knots)?” HLT Min01
“CHG ALT (ft)?” HLT Min02
“DIST (n.m.)?” HLT Min03
( MR01 * MR02 ) ÷
( 60 * ( MR03 x^2 + (
MR02 ÷ MR0F ) x^2
)   √ = “ROC:”

Example:

Input:
TAS = 87 knots
CHG ALT = 4800 ft
DIST = 13.3 n.m.

Result:
522.3878955 ft/min

Source:  “Rate of Climb and Descent” HP 65 Aviation Pac-1 Hewlett Packard.  1974

Eddie


All original content copyright, © 2011-2018.  Edward Shore.   Unauthorized use and/or unauthorized distribution for commercial purposes without express and written permission from the author is strictly prohibited.  This blog entry may be distributed for noncommercial purposes, provided that full credit is given to the author.  Please contact the author if you have questions.

Thursday, July 12, 2018

Fun with the Radio Shack EC-4026



Fun with the Radio Shack EC-4026 

(Equivalent of the Casio fx-4500P)

Programming Notes

 


The syntax for prompting for variables and displaying results are slightly different from the usual Casio programming language (as I mentioned, the EC-4026 is a clone of the fx-4500P).  Check out the unusual If-Then-Else-End structure as well. 

Prompting Syntax:
{var} : var “prompt string”

Example:
 {X}: X”ENTER X”

Display Syntax:
Calculation
“Display string”   (solid right triangle, [2ndF] [↑])

Example: 
X
“F(X)=”

The If-Then-Else-End Structure:
If condition do if the condition is true do if condition is false   (clear right triangle, [2ndF] [√])

Note:  I symbolize the [x^y] by ^.

Finding the Monthly Payment of a Mortgage with Total Interest Paid and Total Cash Outflow

Program MORTGAGE:

L1  Fix 2
L2 {A}: A”LOAN AMOUNT”
L3 {Y}: Y”YEARS”
L4 {I}: I”RATE”
L5 I = I/1200
L6 N = Y*12
L7 P = A*(I(1+I)^N)/((1+I)^N-1)
L8 “MONTHLY PMT”
L9 N*P
L10 “OUTFLOW”
L11 N*P-A
L12 “TOTAL INTEREST”
L13 Norm

Example:

A:  Loan is $250,000.00
Y:  30 years
I: Interest rate of 4%

Results:

P:  Payment:  $1,193.59
Outflow:  $429,673.77
Total Interest:  $179,673.77

Midlength, Height, and Area of a Trapezoid



Program TRAPEZIOD:

L1 {A}
L2 {B}
L3 {C}
L4 {D}
L5 H = √((-A+B+C+D)*(A-B+C+D)*(A-B+C-D)*(A-B-C+D))/(2*Abs(B-A))
L6 M = (A+B)/2
L7 K = M*H
L8 M
L9 “MIDLENGTH”
L10 H
L11 “HEIGHT”
L12 K
L13 “AREA”


Quadratic Equation A*x^2 + B*x + C = 0

Program QUAD:

L1 {A}: A”A”
L2 {B}: B”B”
L3 {C}: C”C”
L4 D = B^2-4*A*C
L5 D<0 Goto 1
L6 X = (-B + √D)/(2A)
L7 Y = (-B - √D)/(2A)
L8 Goto 0
L9 Lbl 1
L10 X = -B/(2A)
L11 “REAL”
L12 Y = √(Abs D)/(2A)
L13 “IMAG”
L14 Lbl 0
L15 “DONE”

Example:

3x^2 + 6x – 1 = 0; A = 3, B = 6, C = -1
Result:  0.154700538, -2.154700538

3x^2 + 6x + 10 = 0; A = 3, B = 6, C = 10
Result:  REAL: -1, IMAG: 1.527525232.  -1 ± 1.527525232i

Minimum Loss Matching



Variables:

Input: Y = Z0, Z = Z1

Output:

R = R1
S = R2
L = Loss Marching

Program MINLOSS:

L1 1:  “Z1<Z0”
L2 {Y}: Y”Z0”
L3 {Z}: Z”Z1”
L4 L = √(1 – Z/Y)
L5 R = Y*L: “R1”
L6 S = Z/L: “R2”
L7 L = 20 log (√(Y/Z) + √(Y/Z – 1)): “LOSS”

Example:

Input:


Y: Z0: 15
Z: Z1: 10

Output:

R1: 8.66025 Ω
R2:  17.32051 Ω
Loss:  5.71948

Add Two Polar Numbers

Polar and Rectangular conversions

Variable
Rectangular Results
Polar Results
V
x
r
W
y
θ

Program ADDPOLAR:

L1 {R}: R”R1”
L2 {S}: S”ANG1”
L3 Rec(R,S)
L4 R = V: S = W
L5 {V}: V”R2”
L6 {W}: W”ANG2”
L7 Rec(V,W)
L8 R = R+V: S = S+W
L9 Pol(R,S)
L10 V: “R SUM”
L11 W: “ANG SUM”

Example:

4 20° + 3 11 ° (In Degrees Mode)

Result (rounded to 4 digits): 6.9789 16.1442°

How to Handle a Tax Bracket (Simple Sample)

Take a sample (and simplified) tax bracket, where income is X:

0 < X ≤ 200:  tax rate is 10% of X
200 < X ≤ 600:  tax rate is 13% of X
600 < X: tax rate is 16% of X

Program:

L1 {X}: X”X”
L2 X > 600 P = 16: Goto 1
L3 X > 200 P = 13: Goto 1
L4 P = 10
L5 Lbl
L6 X * P/100


Eddie

All original content copyright, © 2011-2018.  Edward Shore.   Unauthorized use and/or unauthorized distribution for commercial purposes without express and written permission from the author is strictly prohibited.  This blog entry may be distributed for noncommercial purposes, provided that full credit is given to the author.  Please contact the author if you have questions.

Sunday, July 8, 2018

Fun with the Radio Shack EC-4004

Fun with the Radio Shack EC-4004


Complex Number Multiplication

(a + bi) * (c + di) = (a*c – b*d) + (b*c + a*d)i

Store values in the following memory registers before running the program:

K1 = a
K2 = b
K3 = c
K4 = d

Output is stored in registers K5 (real part) and K6 (imaginary part).

Program:

Kout 1
*
Kout 3
-
Kout 2
*
Kout 4
=
Kin 5
HLT
Kout 2
*
Kout 3
+
Kout 1
*
Kout 4
=
Kin 6

Example:

(-8 + 3i)*(6 + 3i)   (K1 = -8, K2 = 3, K3 = 6, K4 = 3)

Result:  -57 – 6i (K5 = -57, K6 = -6)]

Product of Integers

The following program will between and b:  Product = a * (a + 1) * (a + 2) * … * b

P = Π n from n = a to b

Store values in the following memory registers before running the program:

K1 = a
M = b
K2 = 1 (store 1 in K2 each time)

Program:

Kout 1
Kin* 2
1
Kin+ 1
Kout 1
X ≤ M
Kout 2

Example:  Π n from n = 5 to 8:  P = 5 * 6 * 7 * 8

Store 5 in K1, 8 in M (Inv Min), 1 in K2. 

Heron’s Formula



The program calculates the area of the triangle.  Store the length of the sides in registers K1, K2, and K3.  The register K4 is used in the calculation and ultimately have the area.

K4 = (K1 + K2 + K3)/2

Area = (K4 * (K4 – K1) * (K4 – K2) * (K4 – K3))

Program:

Kout 1
Min
Kout 2
M+
Kout 3
M+
MR
÷
2
=
Min
Kin 4
MR
-
Kout 1
=
Kin* 4
MR
-
Kout 2
=
Kin* 4
MR
-
Kout 3
=
Kin* 4
Kout 4
Kin 4

Example:

K1 = 16.4, K2 = 13.8, K3 = 11.4

Area = 77.60164947

Catenaries



The program calculates the length of the wire in a catenary (2*s). 

Input:

K1 = Horizontal Tension
K2 = Weight of the wire (lb-ft, N, etc)
K3 = half of the distance between the poles

Program:

Kout 1
÷
Kout 2
*
(
Kout 2
*
Kout 3
÷
Kout 1
)
sinh
=
*
2
=

Example:

Input:

K1 (H) = 40N
K2 (weight) = 0.227 N
K3 (half distance between poles) = 32.6 m

Result: 65.5726 m

Source:  Chris M. Alley and Brenda M. Cornitius TI-36 Solar Guidebook Texas Instruments. 1985.

Mass Dragged on the Table by a Pulley



The program solves the following systems:

T – M1*a = μ*M1*g
T + M2*a = M2*g

Input:

K1 = mass 1 in kg
K2 = mass 2 in kg
K3 = friction of the table factor (μ)

Output:

K4 = acceleration (a) m/s^2
K5 = tension of the rope (N)

Tension is displayed first, then acceleration

SI units are assumed, where g = 9.80665 m/s^2 (Earth’s gravity constant)

Program:

9
.
8
0
6
6
5
Kin 4
*
(
Kout 2
Kin 5
-
Kout 1
Kin+ 5
*
Kout 3
)
=
÷
Kout 5
=
Kin 5
HLT
Kin- 4

Example:

K1 = 4.3 kg (mass 1)
K2 = 6.4 kg (mass 2)
K3 = 0.1 (friction μ)

Results:

T = 27.7445 N (tension, K5)
a = 5.47156 m/s^2 (acceleration, K4)

Eddie


All original content copyright, © 2011-2018.  Edward Shore.   Unauthorized use and/or unauthorized distribution for commercial purposes without express and written permission from the author is strictly prohibited.  This blog entry may be distributed for noncommercial purposes, provided that full credit is given to the author.  Please contact the author if you have questions.

Retro Review: Casio fx-450 Calculator


Retro Review:  Casio fx-450 Calculator



General Information

Company:  Casio
Type:  Solar Scientific Algebraic (postfix)
Memory:  1 (store, recall, M+)
Years:  1983 (probably produced during the 1980s with various editions)
Original Cost: Unknown, my guess is $20-$30

Casio Ledudu’s page on fx-450:  http://casio.ledudu.com/pockets.asp?type=1334&lg=eng

It’s a Folding Calculator!

The Casio fx-450 is a folding scientific calculator: one side has the normal, plastic keys with the display and solar panel.  The scientific functions are located on the other panel are touch, rubber-like keys.  The large amount of keys allows for a relatively uncrowded keyboard since the shift key only affects a few keys. 

Modes included on fx-450:

* Single Variable Statistics

* Base Conversions with Boolean conversions (BIN, OCT, HEX)

In addition, the fx-450 has fraction calculations and nine scientific constants (by pressing [MODE] [SHIFT] [1-9]).  The constants, with the exception of the speed of light, have older values (they were updated as of the 2014 CODATA) and they are:

1. Speed of Light (c)
2. Plank’s constant (h)
3. Universal gravitational constant (G)
4. Electron charge (e)
5. Mass of an electron (me)
6. Atomic mass constant (u)
7. Avogadro’s constant (Na)
8. Boltzmann constant (k)
9. Molar volume of ideal gas (Vm)

Verdict

I like the idea of a folding keyboard, especially one of this design.  However, I recommend that you take extra care of the calculator. If the calculator was shipped in bubble wrap, I would keep the bubble wrap and store the calculator.  A concern is the contacts to the scientific keys could be worn. 

The fx-450 is a multi-function scientific calculator with a great set of features and it makes a good collector’s item. 

Eddie


All original content copyright, © 2011-2018.  Edward Shore.   Unauthorized use and/or unauthorized distribution for commercial purposes without express and written permission from the author is strictly prohibited.  This blog entry may be distributed for noncommercial purposes, provided that full credit is given to the author.  Please contact the author if you have questions.

Wednesday, July 4, 2018

Fun with the HP 15C


Fun with the HP 15C

Happy Independence Day, United States!

Fractional Derivative:  kth Derivative of f(x) = x^n

This program calculates the kth derivative of x^n. The program allows for partial derivatives of x^n (where k is not an integer, such as half-integers).

Formula:

d^k/dx^k x^n = n!/(n-k)! * x^(n-k)

Input:
R0: point (x’)
R1:  n
R2: k

Program:

Step
Key
Code
001
LBL A
42, 21, 11
002
RCL 0
45, 0
003
RCL 1
45, 1
004
RCL - 2
45, 30, 2
005
y^x
14
006
LAST x
43, 36
007
x!
42, 0
008
1/x
15
009
*
20
010
RCL 1
45, 1
011
x!
42, 0
012
*
20
013
RTN
43, 32

Example:

d/dx^4 x^8  at x = 6

R0 = x’ = 6
R1 = n = 8
R2 = k = 4

Result:  2177280

d/dx^1.5 x^3.4 at x = 1

R0 = x’ = 1
R1 = n = 3.4
R2 = k = 1.5

Result:  5.5469

Sight Reduction Table

The program calculates altitude and azimuth of a given celestial body.

Inputs:

R1: Local Hour Angle (LHA), west is positive, east is negative
R2: The observer’s latitude on Earth, north is positive, south is negative (L)
R3: Declination of the celestial’s body, north is positive, south is negative (δ)

Each entry will need to be in decimal format.  If your angels are in HMS (hours-minutes-seconds) format, convert the angels to decimals by H before storing the values.

Formulas:

Altitude: 
H = asin (sin δ sin L + cos δ cos L cos LHA)

Azimuth:
Z = acos ((sin δ – sin L sin H) ÷ (cos H cos L))
If sin LHA < 0 then Z = 360° - Z

Outputs:

Altitude (in decimal), R/S, Azimuth (in decimal)

Program:

Step
Key
Code
001
LBL C
42, 21, 13
002
DEG
43, 7
003
RCL 3
45, 3
004
SIN
23
005
RCL 2
45, 2
006
SIN
23
007
*
20
008
RCL 3
45, 3
009
COS
24
010
RCL 2
45, 2
011
COS
24
012
*
20
013
RCL 1
45, 1
014
COS
24
015
*
20
016
+
40
017
ASIN
43, 23
018
STO 4
44, 4
019
R/S
31
020
SIN
23
021
RCL 2
45, 2
022
SIN
23
023
*
20
024
CHS
16
025
RCL 3
45, 3
026
SIN
23
027
+
40
028
RCL 4
45, 4
029
COS
24
030
RCL 2
45, 2
031
COS
24
032
*
20
033
÷
10
034
ACOS
43, 24
035
STO 5
44, 5
036
RCL 1
45, 1
037
SIN
23
038
TEST 2 (x<0)
43, 30, 2
039
GTO 1
22, 1
040
3
3
041
6
6
042
0
0
043
RCL - 5
45, 30, 5
044
STO 5
44, 5
045
LBL 1
42, 21, 1
046
RCL 5
45, 5
047
RTN
43, 32

Source:  “NAV 1-19A Sight Reduction Table”    HP 65 Navigation Pac.  Hewlett Packard, 1974.

Three Point Lagrangian Interpolation

This program calculates a point (x0, y0) given three known points (x1, y1), (x2, y2), and (x3, y3) where x0 is in between min(x1, x2, x3) and max(x1, x2, x3).  Ideally, x1 < x2 < x3.

Input:

R0 = x0 (on the x stack)

Store before running the program:

R1 = x1, R4 = y1
R2 = x2, R5 = y2
R3 = x3, R6 = y3

Other registers used: R7, R8, R9

Step
Key
Code
001
LBL E
42, 21, 15
002
STO 0
44, 0
003
RCL 4
45, 4
004
STO 7
44, 7
005
RCL 5
45, 5
006
STO 8
44, 8
007
RCL 6
45, 6
008
STO 9
44, 9
009
RCL 0
45, 0
010
RCL - 1
45, 30, 1
011
STO * 8
44, 20, 8
012
STO * 9
44, 20, 9
013
RCL 0
45, 0
014
RCL – 2
45, 30, 2
015
STO * 7
44, 20, 7
016
STO * 9
44, 20, 9
017
RCL 0
45, 0
018
RCL – 3
45, 30, 3
019
STO * 7
44, 20, 7
020
STO * 8
44, 20, 8
021
RCL 1
45, 1
022
RCL – 2
45, 30, 2
023
STO ÷ 7
44, 10, 7
024
CHS
16
025
STO ÷ 8
44, 10, 8
026
RCL 1
45, 1
027
RCL – 3
45, 30, 3
028
STO ÷ 7
44, 10, 7
029
STO ÷ 9
44, 10, 9
030
RCL 2
45, 2
031
RCL – 3
45, 30, 3
032
STO ÷ 8
44, 10, 8
033
STO ÷ 9
44, 10, 9
034
RCL 7
45, 7
035
RCL + 8
45, 40, 8
036
RCL + 9
45, 40, 9
037
RTN
43, 32

Example:

R1 = 5, R4 = 0.4
R2 = 10, R5 = 0.9
R3 = 15, R6 = 1.3

R0 = 12, result: 1.0720

R0 = 8, result: 0.7120

Source:  R. Woodhouse.  “Lagrangian Interpolation Routines” Datafile Summer 1984 Vol. 3 No. 3, Page 14

Quadratic Equation with Complex Coefficients

This program solves the equation where B and C are complex numbers:

x^2 + B*x + C = 0

where the roots are:

x = -B/2 ± (B^2/4 – C)

Store the following values before running:

R1 = real(B),  R2 = imag(B)
R3 = real(C), R4 = imag(C)

Output:

Root 1 (press [ f ], hold (i) for the complex part), R/S, Root 2

Program:

Step
Key
Code
001
LBL C
42, 21, 13
002
GSB 1
32, 1
003
GSB 2
32, 2
004
+
40
005
R/S
31
006
GSB 1
32, 1
007
GSB 2
32, 2
008
-
30
009
RTN
43, 32
010
LBL 1
42, 21, 1
011
RCL 1
45, 1
012
RCL 2
45, 2
013
I
42, 25
014
2
2
015
CHS
16
016
÷
10
017
RTN
43, 32
018
LBL 2
42, 21, 2
019
RCL 1
45, 1
020
RCL 2
45, 2
021
I
42, 25
022
x^2
43, 11
023
4
4
024
÷
10
025
RCL 3
45, 3
026
RCL 4
45, 4
027
I
42, 25
028
-
30
029
11
030
RTN
43, 32

Example:

x^2 + (-1 + i)*x + (3i) = 0

R1 = -1, R2 = 1
R3 = 0, R4 = 3

Results:
1.8229 – 1.8229i
-0.8229 + 0.8229i

x^2 + 3*x + (-5 + 6i) = 0

R1 = 3, R2 = 0
R3 = -5, R4 = 6

Results:
1.3862 – 1.0394i
-4.3862 + 1.0394i

Eddie

All original content copyright, © 2011-2018.  Edward Shore.   Unauthorized use and/or unauthorized distribution for commercial purposes without express and written permission from the author is strictly prohibited.  This blog entry may be distributed for noncommercial purposes, provided that full credit is given to the author.  Please contact the author if you have questions.

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