**One Week to HHC 2018**

**It's only one week to HHC 2018, the annual HP calculator conference. This year's conference will be in San Jose, California. As always I am excited.**

http://hhuc.us/2018/

Eddie

A blog is that is all about mathematics and calculators, two of my passions in life.

http://hhuc.us/2018/

Eddie

The following program, written by Stefanescu Horatiu, calculates the intersection point of the two diagonals of a quadrilateral (partulator in Romanian).

The program takes place in a directory PATRULATERDIAGONALE. In order to type in the program, you will need to create a directory by using the CRDIR command.

This program also works on the HP 49G series (48gii, 49G, 49g+) and the HP 50g.

Note: You are going to notice how all the subroutines flow together, as the first program calls the next program. You will need to enter and store all the programs for the entire routine to work correctly.

On a personal note, I like how the text is spelled out one letter at time. Hoartiu accomplishes this by using a FOR-NEXT structure which includes the commands 1 I SUB 1 DISP. (with I as the counter variable).

The text of the program is in Romanian.

The program is presented here with permission from the author, with full credit going to Stefanescu Horatiu. I thank Horatiu in allowing me to feature his work on my blog.

STARTDIAGONALE:

<< CLEAR CLLCD 1 110 FOR I

"ACEST PROGRAM CALCUL

EAZA COORDONATELE PUN

CTULUI DE INTERSECTIE

A DIAGONALELOR UNUI

PATRULATER OARECARE."

1 I SUB 1 DISP

NEXT 0 WAIT

INTRODUCERE >>

INTRODUCERE: (User input screen)

<< CLLCD

"COORDONATE PATRULATER"

{"Ax" "Ay" "Bx"

"By" "Cx" "Cy" "Dx"

"Dy" } { 2 4 } { }

{ } INFORM DROP

OBJ→ DROP 'DY' STO

'DX' STO 'CY' STO

'CX' STO 'BY' STO

'BX' STO 'AY' STO

'AX' STO CLLCD

EMURILE >>

EMURILE: (the start of the calculation routines)

<< 'CY-AY' →NUM 'M1' STO

'-AX*(CY-AY)' →NUM 'M2' STO

'CX-AX' →NUM 'M3' STO

'-AY*(CX-AX)' →NUM 'M4' STO

ENURILE >>

ENURILE:

<< 'BY-DY' →NUM 'N1' STO

'-DX*(BY-DY)' →NUM 'N2' STO

'BX-DX' →NUM 'N3' STO

'-DY*(BX-DX)' →NUM 'N4' STO

ESURILE >>

ESURILE:

<< 'N1-N3*M1/M3' →NUM 'S1' STO

'N3*(M2-M4)/M3+N4-N2' →NUM 'S2' STO

PURILE >>

PURILE:

<< 'S2/S1' →NUM 'PX' STO

'(PX*M1+M2-M4)/M3' →NUM 'PY' STO

REZULTATE >>

REZULTATE: (display the results)

<< CLLCD 1 59

FOR I

"Coordonate punct de

intersectie ale dia

gonalelor: P(x,y)"

1 I SUB 1 DISP NEXT 4 FIX

"P(" PX + →STR ";" +

→STR PY + →STR ")"

+ →STR 5 DISP 0 WAIT

STERG >>

STERG: (cleanup, purge working variables)

<< { AX AY BX BY CX

CY DX DY PX PY M1

M2 M3 M4 N1 N2 N3

N4 S1 S2 } PURGE

CLLCD CLEAR >>

Set your calculator the folder PATRULATERDIAGONALE. Run STARTDIAGONALE and enter the coordinates. The rest of the program runs automatically. Start with the left hand corner and go clockwise.

Note: I typed Horatiu's program on an HP 49G. In REZULTATE, for some reason I couldn't get the FIX 4 to take effect, even when I switched the calculator to Approximate mode. So in order to get both PX and PY on the screen, I added a carriage return character (↲, [right shift] [ 2 ]) after the semicolon. This creates a new line allowing both coordinates to be displayed.

Example 1: (Horatiu's example)

A: (ax, ay): (2, 10)

B: (bx, by): (11, 12)

C: (cx, cy): (13, 6)

D: (dx, dy): (1, 4)

P: (px, py): (6.46875, 8.375)

FIX 4: (6.4688, 8.3750)

Example 2: (my own example)

A: (ax, ay): (0, 8)

B: (bx, by): (5, 12)

C: (cx, cy): (7, 7)

D: (dx, dy): (2, 1)

P: (px, py): (3.72649999999, 7.4625)

FIX 4: (3.7265, 7.4625)

Source:

Horatiu, Stefanescu "Calculul Coordonatelor Punctului de Intersectie A Diagonalelor Unui Partulater Oarecare" 2018.

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.

Introduction: Wow That's Fast!

Recently, there is a discussion on the Museum of HP Calculators forum on "postfix algebraic scientific calculators still in production". The conversation turned to two-key rollover which allowed for fast typing on the calculator. A member ijabott, directed us to a three minute snippet of a YouTube video (https://www.youtube.com/watch?v=WwGL4Z__Ufc&feature=youtu.be). The video featured Asuka Kamimura, a champion of speed calculating, quickly adding a long list of numbers with great accuracy. I was blown away on how she quickly keyed in those numbers. The video explained that Kamimura was going 9 keystrokes a second.*

The video also explained that are calculator clubs in Japanese high schools that practice calculator speed typing for seven hours on Saturdays and Sundays. There are also calculator speed contests in Japan. If anyone reading this has the link or information for the 2018 or even the upcoming 2019 contest, please let me know.

The video also shows a technique on how fast calculating can be accomplished (starts at the 2:59 mark of the above video):

Thumb works on the 0 key only.

The index finger covers the 1-4-7 keys, along with the 00 and any keys on the left side of the keyboard.

The middle finger covers the decimal point, and the row with the 2-5-8 keys.

The ring finger covers the 3-6-9 row, along with the subtraction, multiplication, and division keys. The ring finger also has the equals key.

Finally, little finger is for the plus key.

Regarding the setup and the keys on the calculator, your mileage may vary. The setup present for right-hand users, hence for left-handed users will have to adjust accordingly (thumb works on the plus key, index works with 3-6-9, middle has 2-5-8, ring has 1-4-7, and little has the 0 key for left-handed users).

The calculator shown in the video is a Casio ND-26S (0:45). It is a Japanese model, also designated as a "Study Cal". Also featured is the Casio AZ-25S (3:33), a "Study Cal". According to Casio, "Study Cal" are sold to schools only.

Here is a picture of the ND-26S from the Casio Calculator Collectors website: http://www.casio-calculator.com/Museum/Pages/NNN/ND-26S/Casio%20ND-26S.html

Here in the United States, Casio (and Canon) sells calculators that allow for fast typing. If you are interested, look for the larger desktop type of calculators. Pictured below are two examples:

Casio WS-320MT

Casio JF-100BM

Casio WS-320MT (left), Casio JF-100BM (right) |

Note: I think all the newer keyboards on Casio calculators are designed for fast typing, even the scientific and graphing ones. (fx-991EX Classwiz, fx-CG50)

Try adding the columns as fast and accurately as you can.

For me, it currently takes me about a 1:20 to add up the 40 numbers in each of the blue boxes on my left hand (my non-dominate hand, I'm normally right-handed). This is after 30 minutes of practice.

Videos:

"Japanese people take their calculators very seriously" Posted by Henrik Nieslen on October 26, 2014. https://www.youtube.com/watch?v=WwGL4Z__Ufc&feature=youtu.be

This segment is part of the Japanology series.

"2013 06 13 BEIGN Japaonlogy Calculators" Posted by 13blackmercury on September 4, 2013. https://www.youtube.com/watch?v=1_GVkR0SITo

This particular episode was aired on June 13, 2013.

Discussion on HP Museum of Calculators:

"Postfix algebraic scientific calculators still in production" HP Museum of Calculators Forum. Thread began on September 13, 2018. http://www.hpmuseum.org/forum/thread-11385.html

Calculators (links all retrieved on September 23, 2018):

"ND-26S" Casio Calculator Collectors. http://www.casio-calculator.com/Museum/Pages/NNN/ND-26S/Casio%20ND-26S.html

AZ-26S Product Page. Casio. https://casio.jp/dentaku/products/AZ-26S/ (page is in Japanese)

WM-320MT Product Page. Casio. https://www.casio.com/products/calculators/desktop/wm-320mt (United States)

JF-100BM Product Page. Casio. https://www.casio.com/products/calculators/desktop/jf-100bm (United States)

Have fun! 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.

The program STRNAMES allows the user to store a list of names in a single string. There are only 10 string variables for the TI-84 Plus CE (and in fact, all the the TI-83 and TI-84 families), so if you need to store more than 10 names, a workaround is needed.

This program uses two strings: Str1 and Str2. Str1 is a temporary string variable used to store and edit the list of names. Str2 is the master list of all the names.

In order to make this work, we will need to note where in the string the names start and the length of the names. The two lists used are L₁, the position of each name, and L₂ for the length of each name.

In this program, each name is separated by space.

You will notice that Str2 starts with a space, and the lists L₁ and L₂ have a 0. The TI-84 Plus CE does not allow us to store empty strings or lists.

1. Add a Name: Add a name to the list

2. Delete Last Name: Deletes the last name on the list

3. Clear/Initialize: Clears all the variables. I recommend you start with this option every time you work with a new list of names. Also, if you use other programs or the list or strings for other things, run the Clear/Initialize before beginning.

4. Review: List all the names in order.

5. Erase Any Name: You can erase any name in the list (1st name, 2nd name, 3rd name, etc).

6. Exit: Quits the Program

"2018-09-18 EWS"

Lbl 0

Menu("MENU","ENTER A NAME",A,"DELETE LAST NAME",B,"CLEAR/INITIALIZE",C,"REVIEW",D,"ERASE ANY NAME",E,"EXIT",F)

Lbl A

Input "NAME: ",Str1

augment(L₁,{length(Str2)+1})→L₁

augment(L₂,{length(Str1)}→L₂

Str2+Str1+" "→Str2

Disp "ADDED",Str2,"NAMES:",dim(L₁)-1

Pause

Goto 0

Lbl B

If dim(L₁)≠1

Then

dim(L₁)→I

L₂(I)→B

length(Str2)→C

sub(Str2,1,C-B-1)→Str2

dim(L₁)-1→dim(L₁)

dim(L₂)-1→dim(L₂)

Disp "DONE.",Str2,"NAMES:",dim(L₁)-1

Else

Disp "LIST IS EMPTY."

End

Pause

Goto 0

Lbl C

" "→Str2

{0}→L₁

{0}→L₂

Disp "CLEARED"

Pause

Goto 0

Lbl D

For(I,2,dim(L₁))

L₁(I)→A

L₂(I)→B

dim(L₁)→C

toString(I-1)+"/"+toString(C-1)+": "+sub(Str2,A,B)→Str1

Disp Str1

Wait 0.5

End

Pause

Goto 0

Lbl E

Input "ENTRY NUMBER:",I

I+1→I

dim(L₁)→D

L₂(I)→E

If D=I

Then

Goto B

Else

L₁(I)→A

L₁(I+1)→B

length(Str2)→C

sub(Str2,1,A-1)+sub(Str2,B,C-B)+" "→Str2

For(K,I+1,D)

L₁(K)-E-1→L₁(K-1)

L₂(K)→L₂(K-1)

End

dim(L₁)-1→dim(L₁)

dim(L₂)-1→dim(L₂)

Disp "DONE.",Str2,"NAMES:",dim(L₁)-1

Pause

End

Goto 0

Lbl F

Disp "END PROGRAM"

Try playing with this program.

Example list:

1. Start by initializing, choose option 3.

2. Enter EDDIE. Choose option 1. Press [ 2nd ] [alpha] and type EDDIE. Quotes are not needed (since the Input command will be stored to a string). Str2 = " EDDIE "

3. Enter ANN. Choose option 1. Str2 = " EDDIE ANN "

4. Enter TERRY. Choose option 1. Str2 = " EDDIE ANN TERRY "

5. Let's remove ANN from the list. In our example, ANN is the second name. Choose option 5. Enter 2. The result, Str2 = " EDDIE TERRY "

6. Enter MARK. Choose option 1. Str2 = " EDDIE TERRY MARK "

7. Review the list of names. Choose option 4. The screen will show:

1/3 EDDIE

2/3 TERRY

3/3 MARK

Continue with the example however you want.

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.

The program PRECESS estimate the new position (right ascension (RA), declination (Î´)) of a celestial object given their position in Epoch 2000 with the object’s proper notion.

Estimation formulas:

Change in RA and Î´ before accounting for proper notion

Î”RA = m + n * sin RA * tan Î´ (in seconds)

= 3.07496 + 1.33621 * sin RA * tan Î´ (for epoch 2000)

Î”Î´ = (15 * n) * cos RA (in arcseconds)

= 20.0431 cos RA (epoch 2000)

With m = 3.07496 seconds and n = 1.33621 seconds (for epoch 2000)

For other epochs:

1900: m = 3.0731, n = 1.33678

2100: m = 3.07682, n = 1.33564

Then:

RA_new = (RA_old + Y * (Î”RA + RA_proper) / 3600 ) / 15 (hours)

Î´_new = (Î´_old + Y * (Î”Î´ + Î´_proper) / 3600 (degrees)

Y = years from 2000 (or the appropriate epoch)

For the HP Prime and TI-84 Plus CE versions, click here: http://edspi31415.blogspot.com/2018/09/hp-prime-and-ti-84-plus-ce-precession.html

The key codes for both calculators are the same.

STEP KEY KEY CODES

01 LBL D 61, 41, d

02 DEG 61, 23

03 RCL 0 22, 0

04 →HR 51, 54

05 × 55

06 1 1

07 5 5

08 = 74

09 STO 0 21, 0

10 RCL 1 22, 1

11 →HR 51, 54

12 STO 1 21, 1

13 3 3

14 . 73

15 0 0

16 7 7

17 4 4

18 9 9

19 6 6

20 + 75

21 1 1

22 . 73

23 3 3

24 3 3

25 6 6

26 2 2

27 1 1

28 × 55

29 RCL 0 22, 0

30 SIN 23

31 × 55

32 RCL 1 22, 1

33 TAN 25

34 = 74

35 STO 5 21, 5

36 2 2

37 0 0

38 . 73

39 0 0

40 4 4

41 3 3

42 1 1

43 × 55

44 RCL 0 22, 0

45 COS 24

46 = 74

47 STO 6 21, 6

48 RCL 0 22, 0

49 + 75

50 RCL 4 22, 4

51 × 55

52 ( 33

53 RCL 5 22, 5

54 + 75

55 RCL 3 22, 3

56 ) 34

57 ÷ 45

58 3 3

59 6 6

60 0 0

61 0 0

62 = 74

63 ÷ 45

64 1 1

65 5 5

66 = 74

67 →HMS 61, 54

68 STO 7 21, 7

69 R/S 26

70 RCL 1 22, 1

71 + 75

72 RCL 4 22, 4

73 × 55

74 ( 33

75 RCL 6 22, 6

76 + 75

77 RCL 3 22, 3

78 ) 34

79 ÷ 45

80 3 3

81 6 6

82 0 0

83 0 0

84 = 74

85 →HMS 61, 54

86 STO 8 21, 8

87 RTN 61, 26

Store the following values in the registers:

R0: Initial RA in HH.MMSSSS format

R1: Initial Î´ in DD.MMSSSS format

R2: RA proper notion

R3: Î´ proper notion

R4: number of years from 2000. For 2022, store 22. For 1978, store -22.

Result:

R7: New RA in HH.MMSSSS format, press [ R/S ] to get

R8: New Î´ in DD.MMSSSS format

Estimate the RA and Î´ of Regulus (Alpha Leonis) and Sadalmelik (Alpha Aquarii) for 2020 (Y = 20). (data from Wikipedia)

Epoch 2000: RA = 10h 8m 22.311s, Î´ = +11° 58’ 0.195”

Proper Notion: RA_prop = -0.016582 arcsec/yr, Î´_prop = 0.00556 arcsec/yr

(arcsec = “)

Results:

RA_2020 ≈ 10h 8m 26.56557s (shown as 10°08’26.56557”)

‘Î´_2020 ≈ +11° 52’ 6.06118”

Epoch 2000: RA = 22h 5m 47.03593s, Î´ = -0° 19’ 11.4568”

Proper Notion: RA_prop = 1.216667 * 10^-3 arcsec/yr, Î´_prop = -0.00939 arcsec/yr

Result:

RA_2020 ≈ 22h 5m 51.14225s

Î´ ≈ -0° 13’ 19.5407”

Convert mas/yr to arcsec/yr:

For RA: (x/15) /1000

For Î´: x/1000

Sources:

Jones, Aubrey. __Mathematical Astronomy with a Pocket Calculator__ John Wiley & Sons: New York. Printed in Great Britain. 1978. ISBN 0 470 26552 3

Meeus, Jean. __Astronomical Algorithms__ William-Bell, Inc. Richmond, VA 1991. ISBN 0-943396-35-2

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.

The program presented in today's blog entry will calculate the qualifying loan amount given the following:

* Loan's annual interest rate and term (in years)

* The borrower's monthly gross income

* The borrower's monthly non-property related debt (credit cards, auto loans, store bought appliances on credit, etc). Do not include utilities or phone bills.

* The estimated monthly property tax and insurance. For this program, combine the two amounts.

Before running the program, store the following amounts in the following registers:

R0: Monthly Income

R1: Monthly Debt

R2: Monthly Property Taxes and Insurance

R3: Annual Interest Rate

R4: Term

The down payment is not taken into consideration.

The result is the loan amount using the standard 28:36 ratio (stored in register R5). The 28:36 ratio is the guideline that the borrower spends no more than 28% of their income on housing expenses, and no more than 36% of their income on all debt service.

The key codes for most steps are the same. Lines where the key codes are different are noted, particularly the percentage function.

STEP KEY KEY CODE

01 LBL E 61, 41, E

02 FIX 2 51, 33, 2

03 RCL 0 22, 0

04 × 55

05 3 3

06 6 6

07 % HP 20S: 51,14 HP 21S: 51, 53

08 = 74

09 - 65

10 RCL 1 22, 1

11 = 74

12 STO 6 21, 6

13 RCL 0 22, 0

14 × 55

15 2 2

16 8 8

17 % HP 20S: 51,14 HP 21S: 51, 53

18 = 74

19 STO 7 21, 7

20 RCL 6 22, 6

21 INPUT 31

22 RCL 7 22, 7

23 X≤Y? 61, 42

24 SWAP 51, 31

25 STO 8 21, 8

26 RCL 2 22, 2

27 STO - 8 21, 65, 8

28 1 1

29 - 65

30 ( 33

31 1 1

32 + 75

33 RCL 3 22, 3

34 ÷ 45

35 1 1

36 2 2

37 0 0

38 0 0

39 ) 34

40 Y^X 14

41 ( 33

42 1 1

43 2 2

44 +/- 32

45 × 55

46 RCL 4 22, 4

47 ) 34

48 = 74

49 ÷ 45

50 ( 33

51 RCL 3 22, 3

52 ÷ 45

53 1 1

54 2 2

55 0 0

56 0 0

57 ) 34

58 = 74

59 × 55

60 RCL 8 22, 8

61 = 74

62 STO 5 21, 5

63 RTN 61, 26

R0: Monthly Income = $4,485.00

R1: Monthly Debt = $375.00

R2: Monthly Property Taxes and Insurance = $126.83

R3: Annual Interest Rate = 5%

R4: Term = 30 years

Result: $207,288.60

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.

We can approximate the stopping distance (in feet) of a vehicle on dry pavement given the vehicle's speed (in miles per hour, mph) by the formula:

y = 3.85714285714*10^-2 * x^2 + 1.44504201681 * x + 0.64915966369

or

y = 27/200 * x^2 + 1.44504201681 * x + 0.64915966369

y: stopping distance on dry pavement, feet

x: speed of vehicle, mph

Assumptions:

* The vehicle is assumed to be a passenger vehicle.

* The reaction time is 1 second and the deceleration rate is 28 ft/s.

The program listed rounds all results to one decimal place.

STEP KEY KEY CODE

01 LBL B 61, 41, b

02 STO 0 21, 0

03 x^2 51, 11

04 × 55

05 2 2

06 7 7

07 ÷ 45

08 7 7

09 0 0

10 0 0

11 + 75

12 RCL 0 22, 0

13 × 55

14 1 1

15 . 73

16 4 4

17 4 4

18 5 5

19 0 0

20 4 4

21 2 2

22 0 0

23 1 1

24 6 6

25 8 8

26 1 1

27 + 75

28 . 73

29 6 6

30 4 4

31 9 9

32 1 1

33 5 5

34 9 9

35 6 6

36 6 6

37 3 3

38 9 9

39 = 74

40 STO 1 21, 1

41 FIX 1 51, 33, 1

42 RTN 61, 26

Examples

Input: 25 mph, Result: 60.9 ft

Input: 40 mph, Result: 120.2 ft

Input: 65 mph, Result: 257.5 ft

Source:

Glover, Thomas J. __Pocket Ref__ 4th Edition. Sequoia Publishing, Inc. Littleton, CO. 2012

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.

The following program will allow the user to round any positive number to any number of decimal places, regardless of fixed decimal settings.

This is based off the algorithm:

x_rounded = int(10^n * x + 0.5) ÷ 10^n

Note: You can check out the programs for the HP 12C and DM 41L/HP 41C here:

http://edspi31415.blogspot.com/2018/08/hp-12c-platinum-and-dm-41l-rounding.html

Step Key Key Code

01 LBL C 61, 41, C

02 10^x 51, 12

03 STO 0 21, 0

04 SWAP 51, 31

05 × 55

06 RCL 0 22, 0

07 + 75

08 . 73

09 5 5

10 = 74

11 IP 51, 45

12 ÷ 45

13 RCL 0 22, 0

14 = 74

15 RTN 61, 26

Enter x, press [INPUT], enter n (number of decimal places)

For these examples, I have set the calculator in ALL setting ( [right shift], [ ) ] )

Example 1: Round Ï€ to 4 places.

Ï€ [ INPUT ] 4 [XEQ] (C)

Result: 3.1416

Example 2: Round e^2.2 to 6 places

2.2 [e^x] [INPUT] 6 [XEQ] (C)

Result: 9.025013

Source:

Keith Oldham, Jan Myland, and Jerome Spanier

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.

The following program calculates the area of a triangle knowing the three lengths. The area is determined by Heron's formula:

Area: √(s * (s - a) * (s - b) * (s - c)) where s = (a + b + c)/2

Store the lengths of the triangle in registers R0, R1, and R2 respectively.

Results are stored in the following registers:

R3: s

R4: area

The key codes for both calculators are the same.

STEP KEY KEY CODE

01 LBL A 61, 41, A

02 RCL 0 22, 0

03 STO 3 21, 3

04 RCL 1 22, 1

05 STO+3 21, 75, 3

06 RCL 2 22, 2

07 STO+3 21, 75, 3

08 2 2

09 STO÷3 21, 45, 3

10 RCL 3 22, 3

11 STO 4 21, 4

12 RCL 3 22, 3

13 - 65

14 RCL 0 22, 0

15 = 74

16 STO×4 21, 55, 4

17 RCL 3 22, 3

18 - 65

19 RCL 1 22, 1

20 = 74

21 STO×4 21, 55, 4

22 RCL 3 22, 3

23 - 65

24 RCL 2 22, 2

25 = 74

26 STO×4 21, 55, 4

27 RCL 4 22, 4

28 √ 11

29 STO 4 21, 4

30 RTN 61, 26

R0 = 17, R1 = 18, R2 = 21. Result: Area: 148.833238744

Note: I switched computers last week. For the last few years, I used Microsoft Word but for the time being I am going to use WordPad. Let's see how this goes. Fortunately I can still can use Unicode characters with Alt+X. For example, I can type 221A, then type [Alt] + [ X ] to get the square root character. Unfortunately, WordPad doesn't have spell check.

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.

Company: Calculated Industries

Type: Finance/Banking

Display: 9 digit
alpha-numeric display

Power: 2 LR44 or 2
A76 batteries

Memory: 1 independent
memory (store, recall, M+, M-)

Years: 2004 – late 2000s

Original Cost: $49.95

Documentation: Manual,
though it is no longer available online

The Qualifier Plus IIImx is a finance calculator that seems
to be made for a specific client, World Savings. The model has a World Savings logo on it, and
any Armadillo Gear protective cover that came with it.

Interesting to note that in 2006 that Wachovia Corporation
purchased Golden West Financial Corporation, World Savings’ parent corporation,
only for Wachovia itself to be purchased by Wells Fargo in 2008. [[S1]]

Let’s get to the regular known features of the Qualifier
Plus IIImx:

* Time Value of Money (payments are assumed to be monthly,
but can be adjusted), this can include price and down payment

* Amortization of Loans

* Interest Only Payment Calculations

* Payment Calculations:
P&I (principal and interest), PITI (principal, interest, property
tax, property insurance), TOTAL (PITI plus monthly expenses)

* Qualifying Loan Amounts (two slots to store two ratios,
Qual 1 defaults to the standard 28:36 debt/income ratio)

* Rent vs. Buy Analysis: given monthly rent, loan amounts,
property tax, property insurance, the renter’s income tax bracket

* Date calculations:
2-digit year entry. I’m not sure what this time period covers because
the pocket guide doesn’t state. Through
entering various dates and using www.dayoftheweek.org,
the dates seem to range from January 1, 1960 (Friday) to December 31, 2059
(Wednesday).

One neat thing with the Qualifier Plus IIImx (this really
goes for all the Calculated Industries financial and real estate calculators) is
that some of the entries can determine percentage rates or dollar amounts
without additional key strokes.
Generally, any entry of 100 or less is treated as a percent, above 100
is treated as dollars.

Example:

20 [ Dn Pmt ] sets the down payment at 20% of the price

20000 [ Dn Pmt ] sets the down payment at $20,000

Other keys that work this way: [ Shift ] [ 7 ] (annual property tax), [Shift]
[ 8 ] (annual property insurance), [Shift] [ 9 ] (annual mortgage insurance)

So far, so good. Now
let’s get to the controversy…

I am grateful that when I bought the calculator it still had
its pocket reference guide [[S2]] otherwise I would have no idea what all the
MARM keys were about. I still don’t
understand all the details, but the MARM keys calculates such loans that were
called “pick-a-payment” loans, which were popular and heavily advertised during
the housing boom in the mid to late 2000s.

In general, “pick-a-payment” loans allowed borrowers to set
a payment where the payment is *less*
than the interest charged for the initial period of the loan. Any interest that wasn’t paid was tacked to
the end the loan. Furthermore, none of
the principal has been paid down during the initial time. I think you can see the problem, by paying too
low in the beginning resulted in a higher loan balance (principal plus unpaid
interest). Furthermore, MARM loans are
rate adjustable. Even with the presence of
caps, it’s not all that comforting when the deferred interested and delay of paying
off principal are taken into account.

In 2010, Wells Fargo (having acquired World Savings and
Wachovia) made a minimum of $50 million in a class action lawsuit over these
types of loans [[S3]], including promises to modify any loans of the borrowers
who made such “pick-a-payment” type of mortgages. Wells Fargo would get in trouble again 2012
when the loan modifications were denied to a lot of affected borrowers. [[S4]]

It shouldn’t be surprising to see why Calculated Industries
discontinued this model and took down any documentation for this
calculator.

Because of the controversial and perhaps infamous nature of
some of this calculator’s features, I am not going to issue a verdict or
recommendation.

Sources:

[[S1]] Wells
Fargo. “World Savings is Now Wells Fargo”
https://www.wellsfargo.com/about/corporate/worldsavings/ Retrieved September 5, 2018

[[S2]] Calculated Industries. __Model 3440: Pocket Reference Guide__. 2004
Guide is not available online.

[[S3]] Orlofsky, Steve – Editor. “Wells Fargo to settle lawsuit over
pick-a-payment loans” Reuters. December 14,
2010. https://www.reuters.com/article/wellsfargo-settlement/wells-fargo-to-settle-lawsuit-over-pick-a-payment-loans-idUSN1427719820101215?feedType=RSS Retrieved September 5, 2018.

[[S4]] Reckard, E. Scott.
“Wells Fargo settlement over ‘pick-a-pay’ home loans is challenged”. Los Angeles Times. December 11, 2012. http://articles.latimes.com/2012/dec/11/business/la-fi-wells-suit-20121211 Retrieved September 9, 2018.

Eddie

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