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HP-35s complex numbers in polar mode - Printable Version

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HP-35s complex numbers in polar mode - Kjetil - 05-17-2020 10:04 PM

Hello,

I bought myself a new HP-35s this winter (2020).

I have a problem with keying in complex numbers i polar mode.
That is when the |absolute value| is a result of an operation,
or if [enter] i pressed just before [blue-shift] [i] [value] [ENTER]

- RPN modus.
- Polar modus
- Emptying the stack. [blue-shift][CLEAR][STK][ENTER]

Example:
[2] [sqrt] [blue-shift] [i] [45] [ENTER]
This gives an error message: SYNTAX ERROR.

Example:
[0.41] [ENTER] [1] [+] [blue-shift] [i] [45] [ENTER]
This gives an error message: SYNTAX ERROR.

Example:
[2] [ENTER] [blue-shift] [i] [45] [ENTER]
This gives an error message: SYNTAX ERROR.


So my question is. How shall I key in the following?:
|sqrt{2}| r{45} (that is 1+i1)


Best regards, Kjetil

RE: HP-35s complex numbers in polar mode - ijabbott - 05-18-2020 08:07 AM

[sqrt] is an operation key, not a number entry key.

You could enter the number as two numbers and multiply them together:

2
[sqrt]
1Θ45
[x]

Or enter the approximate value of sqrt(2) as part of the number:

1.41421356237Θ45
[enter]

Or just enter it in rectangular form since you already know it:

1i1
[enter]

RE: HP-35s complex numbers in polar mode - pinkman - 05-18-2020 09:20 AM

Hello,
The Θ key is made to enter inline values in polar mode, ex: 1.414Θ0.7

I like this answer from ijabbott :
(05-18-2020 08:07 AM)ijabbott Wrote:  2
[sqrt]
1Θ45
[x]

I also suggest using the RAD mode and entering the number in the exponential form (r.e^(iΘ)):
[pi]
[4]
[/]
[i]
[*]
[e^x]
[2]
[SQRT]
[*]

RE: HP-35s complex numbers in polar mode - Kjetil - 05-18-2020 09:21 AM


Ian Abbott,

Thanks a lot for your prompt response.

I like Your first solution that multiplying the “real” number (2 [sqrt]) with 1Θ45.


But when it comes to the two latter solution, I am not able to see those as answers to my question.

I should of course explicitly stated that my example, «keeing in» √2Θ45, was meant as a part of a larger calculation.

Again, thanks a lot for taking your time.


Best regards, Kjetil

RE: HP-35s complex numbers in polar mode - Kjetil - 05-18-2020 09:55 AM

Pinkman

Thanks a lot for Your comments!

Using exponential form (r e^(iΘ)) was interesting. – It is of course due to my limited math skills, but I have to look into Your suggestion more closely.


Best regards, Kjetil

RE: HP-35s complex numbers in polar mode - Kjetil - 05-18-2020 12:36 PM

Thanks to both for Your help. This is, as far as I could see, the right solution:

2 [√] 1 [Θ] 45 [×]


By the way; on my old HP-42S, (in polar mode), I could just press:

2 [√] 45 [COMPLEX]



Best regards, Kjetil

RE: HP-35s complex numbers in polar mode - pinkman - 05-18-2020 06:15 PM

We all wished the 35s was a 42s...
But it’s a good calculator and you could add a small program to create the same function.

Code:

C001 LBL C
C002 ENTER
C003 SIN
C004 i
C005 x
C006 x<>y
C007 COS
C008 +
C009 x
C010 RTN

Usage:
2
[SQRT]
45
XEQ C
[Enter]

I used the z = r(i.sinΘ+ cosΘ) form to handle deg or rad modes. Unfortunately there is no flag giving the polar or rectangular mode, otherwise we could have simulated the whole behavior of the 42s.

Regards,
Thibault