HP 42s Time value of Money

[JCT]

Hi all...am new to the forum. I used a 28s in college (mechanical engineering) but sadly sold it at a yard sale years ago.

I now use a 12c at my desk and recently became the proud owner of a 42s.

Today is my first day with it and the manual lists a program for the solver for the time value of money. I was able to input the entire program but it is not working. I think the problem lies in line 14. The book has the following entry...

14 STO ST T

I don't know how to put a space between the "ST" and the "T" so in inserted the punctuation mark "_" so my line 14 now looks like this...

14 STO "ST_T"

So I guess I have two questions...

1) Do I use the function "STO" or do I type the alpha letters STO.

2) Either way, I need a space between the ST and the T and possibly even after the "STO"...how do I enter a space?

Thanks,

JT

[Jeff_Kearns]

http://www.hpmuseum.org/cgi-sys/cgiwrap/...read=68077

Please refer to the above link for an accurate TVMprogram for the HP-42S.

Jeff K

[Gene]

""I don't know how to put a space between the "ST" and the "T" so in inserted the punctuation mark "_" s ""



For something like STO ST T

Press STO then the decimal point then the letter T

[Jeff_Kearns]

(05-07-2015 04:37 PM)JCT Wrote:  Hi all...am new to the forum. I used a 28s in college (mechanical engineering) but sadly sold it at a yard sale years ago.

I now use a 12c at my desk and recently became the proud owner of a 42s.

Today is my first day with it and the manual lists a program for the solver for the time value of money. I was able to input the entire program but it is not working. I think the problem lies in line 14. The book has the following entry...

14 STO ST T

I don't know how to put a space between the "ST" and the "T" so in inserted the punctuation mark "_" so my line 14 now looks like this...

14 STO "ST_T"

So I guess I have two questions...

1) Do I use the function "STO" or do I type the alpha letters STO.

2) Either way, I need a space between the ST and the T and possibly even after the "STO"...how do I enter a space?

Thanks,

JT

In Program mode, type STO followed by a '.'. That brings up a menu and you selct the one on the far right: ST T.

Jeff

[John R]

This command stores the value in the X register into the T register. You can execute it with three keystrokes. First press STO, then press . (decimal). You will then see a menu that includes "ST T" as the rightmost entry. Press XEQ to select this entry.

[John R]

Welcome to the MoHPC forum, where every question is immediately answered by three friendly experts. :-)

[JCT]

Thanks guys!!!

I really appreciate it.

Jeff posted a link to the correct TVM program. Am I to assume the one in the manual is incorrect (now that I know how to type STO ST T)?

Thanks,

JT

[Jeff_Kearns]

(05-07-2015 05:23 PM)JCT Wrote:  Thanks guys!!!

I really appreciate it.

Jeff posted a link to the correct TVM program. Am I to assume the one in the manual is incorrect (now that I know how to type STO ST T)?

Thanks,

JT

The program listed in the user's manual is not as precise as the one in the link. It loses significant digits due to round-off errors for extreme cases of large numbers of compounding periods or really small periodic interest rates. Check out the examples in the General Software section on this site (example) and search the forum for additional info on this matter. The HP-15C Advanced Functions Handbook (available on the Museum DVD Set) has a section on this.

Try them both out and compare for the following case:

"Many Pennies (alternatively known as A Penny for Your Thoughts):

A corporation retains Susan as a scientific and engineering consultant at a fee of one penny per second for her thoughts, paid every second of every day for a year.
Rather than distract her with the sounds of pennies dropping, the corporation proposes to deposit them for her into a bank account in which interest accrues at the rate of 11.25 percent per annum compounded every second. At year's end these pennies will accumulate to a sum

total = (payment) X ((1+i/n)^n-1)/(i/n)

where payment = $0.01 = one penny per second,
i = 0.1125 = 11.25 percent per annum interest rate,
n = 60 X 60 X 24 X 365 = number of seconds in a year.

Using her (INSERT 'favourite' HP calculator) which she programmed with the TVM formula alone, Susan reckons that the total will be $376,877.67. But at year's end the bank account is found to hold $333,783.35 . Is Susan entitled to the $43,094.32 difference?"
31,536,000 STO 1
(11.25/31,536,000) STO 2
0 STO 3
-0.01 STO 4
5 STO I
f SOLVE E

The correct result is: $333,783.35."

Jeff Kearns

[JCT]

(05-07-2015 06:37 PM)Jeff_Kearns Wrote:  

(05-07-2015 05:23 PM)JCT Wrote:  Thanks guys!!!

I really appreciate it.

Jeff posted a link to the correct TVM program. Am I to assume the one in the manual is incorrect (now that I know how to type STO ST T)?

Thanks,

JT

The program listed in the user's manual is not as precise as the one in the link. It loses significant digits due to round-off errors for extreme cases of large numbers of compounding periods or really small periodic interest rates. Check out the examples in the General Software section on this site (example) and search the forum for additional info on this matter. The HP-15C Advanced Functions Handbook (available on the Museum DVD Set) has a section on this.

Try them both out and compare for the following case:

"Many Pennies (alternatively known as A Penny for Your Thoughts):

A corporation retains Susan as a scientific and engineering consultant at a fee of one penny per second for her thoughts, paid every second of every day for a year.
Rather than distract her with the sounds of pennies dropping, the corporation proposes to deposit them for her into a bank account in which interest accrues at the rate of 11.25 percent per annum compounded every second. At year's end these pennies will accumulate to a sum

total = (payment) X ((1+i/n)^n-1)/(i/n)

where payment = $0.01 = one penny per second,
i = 0.1125 = 11.25 percent per annum interest rate,
n = 60 X 60 X 24 X 365 = number of seconds in a year.

Using her (INSERT 'favourite' HP calculator) which she programmed with the TVM formula alone, Susan reckons that the total will be $376,877.67. But at year's end the bank account is found to hold $333,783.35 . Is Susan entitled to the $43,094.32 difference?"
31,536,000 STO 1
(11.25/31,536,000) STO 2
0 STO 3
-0.01 STO 4
5 STO I
f SOLVE E

The correct result is: $333,783.35."

Jeff Kearns

Thanks Jeff.

JT

[lrdheat]

Correct answer on HP 30b, Prime. Can't do directly on CASIO 9869gii, Classpad 400 as they do not allow for more than 9999 payments per year.

[lrdheat]

That's CASIO 9860gii, not 9869.

[lrdheat]

Unless I'm doing something wrong, the TI Nspire doesn't want more than 366 payments per year. The HP 39gii is fine with the problem.