09-16-2014, 03:14 PM
Post: #21
 Gerson W. Barbosa Senior Member Posts: 1,199 Joined: Dec 2013
(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
/

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.

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.
09-17-2014, 01:23 AM
Post: #22
 Thomas Klemm Senior Member Posts: 1,448 Joined: Dec 2013
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.
09-23-2014, 12:15 AM (This post was last modified: 02-17-2015 08:28 PM by Thomas Klemm.)
Post: #23
 Thomas Klemm Senior Member Posts: 1,448 Joined: Dec 2013
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
02-17-2015, 07:36 PM
Post: #24
 PedroLeiva Member Posts: 138 Joined: Jun 2014
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
02-17-2015, 08:26 PM (This post was last modified: 02-17-2015 08:30 PM by Dieter.)
Post: #25
 Dieter Senior Member Posts: 2,398 Joined: Dec 2013
(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
02-17-2015, 08:34 PM
Post: #26
 PedroLeiva Member Posts: 138 Joined: Jun 2014
(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
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