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Gerson W. Barbosa · 09-16-2014, 03:14 PM

(09-16-2014 12:33 PM)Dieter Wrote:
(09-16-2014 01:20 AM)Gerson W. Barbosa Wrote: You can try
RCLx F
RCL F
ABS
/

Instead of

RCLF
SGN
x

starting at step B0014, assuming F is never zero.

If I understand correctly, the sequence

RCL F
SGN
x

shall be replaced by something that does not require a sign function and that also does not use more than one stack level. Your suggestion will do so, but the combination of a multiplication and a subsequent division may degrade accuracy, and, more important, it will not work for F = 0.

So how about this one?

RCL F
ABS
X≠0?
RCL/ F
x

Dieter

In order to address the case F=0, which seems to be a consequence of B=0, I had suggested later in the thread the insertion of x=0? x! between ABS and /. Your suggestion is one step shorter and more efficient, so I would go for it. That's what I was able to come up with while watching an interview on TV. When memory is not an issue (sometimes it is on the 32S-II), I'll definitely use the SGN subroutine replacement, since no stack analysis is necessary.

Regards,

Gerson.

Thomas Klemm · 09-17-2014, 01:23 AM

You don't really need the SIGN function. You can exchange the SQRT with register F and use register arithmetic (lines B12 - B17). But then you don't push F onto the stack. That's why we need to recall F later in line E07.

Code:

B01 LBL B

B02 FIX 9

B03 RCL H

B04 x^2

B05 STO(i)

B06 RCL D

B07 RCL I

B08 SUM -

B09 SUM xy

B10 x<0?

B11 GTO E

B12 SQRT

B13 x<> F

B14 x<0?

B15 RCL- F

B16 x>=0?

B17 RCL+ F

B18 STO J

B19 x<>y

B20 /

B21 RCL J

B22 x#0?

B23 GTO F

B24 CLx

B25 STOP

F01 LBL F

F02 RCL G

F03 x<>y

F04 /

F05 STOP

E01 LBL E

E02 SF 0

E03 +/-

E04 SQRT

E05 RCL D

E06 /

E07 RCL F

E08 R UP

E09 /

E10 STOP

Currently I have troubles with my HP-32II and therefore can't test these changes. But as an inspiration you can have a look at the original code for the HP-15C (lines 057-061 of program B).

HTH
Thomas

PS: Sorry for being late to the party.

Thomas Klemm · (This post was last modified: 02-17-2015 08:28 PM by Thomas Klemm.)

The suggestions in my previous post are flawed. Meanwhile I could fix it. This program works fine with my HP-32SII:

Code:

H01 LBL H

H02 INPUT A

H03 STO D

H04 INPUT B

H05 -2

H06 ÷

H07 STO F

H08 STO H

H09 INPUT C

H10 STO G

H11 STO I

H12 CF 0

H13 SCI 2

A01 LBL A

A02 CLΣ

A03 28

A04 STO i

A05 4

A06 STO(i)

A07 33

A08 STO i

A09 RCL H

A10 STO(i)

A11 RCL÷ D

A12 RND

A13 RCL D

A14 Σ-

A15 RCL I

A16 Σxy

A17 x<>y

A18 STO(i)

A19 R↓

A20 x<>y

A21 RCL H

A22 Σ-

A23 R↓

A24 Σ-

A25 Σxy

A26 ABS

A27 RCL I

A28 ABS

A29 x≤y?

A30 GTO B

A31 ENTER

A32 R↑

A33 STO H

A34 Σxy

A35 STO I

A36 ABS

A37 1E24

A38 ×

A39 RCL G

A40 ABS

A41 x≤y?

A42 GTO A

B01 LBL B

B02 FIX 9

B03 RCL H

B04 x²

B05 STO(i)

B06 RCL D

B07 RCL I

B08 Σ-

B09 Σxy

B10 x<0?

B11 GTO E

B12 SQRT

B13 x<> F

B14 x<0?

B15 RCL- F

B16 x≥0?

B17 RCL+ F

B18 x<> G

B19 x≠0?

B20 RCL÷ G

B21 RCL G

B22 RCL÷ D

B23 STOP

E01 LBL E

E02 SF 0

E03 +/-

E04 SQRT

E05 RCL÷ D

E06 x<>y

E07 RCL F

E08 x<>y

E09 ÷

E10 STOP

This post made me try to understand the algorithm that is used. I posted my findings in an article.

Cheers
Thomas

PedroLeiva · 02-17-2015, 07:36 PM

Dear Members, I have a question about Palmer Hanson program for Hp 35s. I don´t know how to insert steps Q038, 040 and 065= SUM - , from the program listing of Cadillac Quadratic Solver.

Can you please assit me about the order of the keys for that instruction
Thank you in advance, Pedro

Dieter · (This post was last modified: 02-17-2015 08:30 PM by Dieter.)

(02-17-2015 07:36 PM)PedroLeiva Wrote: Can you please assit me about the order of the keys for that instruction

I see this is your first post here, so welcome to the forum. ;-)

In the listing, "Sum" refers to the greek Sigma, so "Sum–" means Σ– (yellow-shifted function of the Σ+ key in the bottom key row). Equally, "Sum xy" means Σxy which is accessed via the SUMS menu (blue-shifted Minus-key).

Dieter

PedroLeiva · 02-17-2015, 08:34 PM

(02-17-2015 08:26 PM)Dieter Wrote:
(02-17-2015 07:36 PM)PedroLeiva Wrote: Can you please assit me about the order of the keys for that instruction

I see this is your first post here, so welcome to the forum. ;-)

In the listing, "Sum" refers to the greek Sigma, so "Sum–" means Σ– (yellow-shifted function of the Σ+ key in the bottom key row). Equally, "Sum xy" means Σxy which is accessed via the SUMS menu (blue-shifted Minus-key).

Dieter

How I did not realize it! Thank you very much for your assistance. Pedro