Musings and comments about our common interest
Here is another simple program that I use in my HP-41CL. (It’s an advantage not to be concerned with memory usage, and even being able to switch different environments!). It was written in very much the same manner as the currency translator.
Our company has factories in both the European Union and USA. All shipments in Europe are denominated in Tons, while all shipments in the US are in pounds. Similarly, while all surface painting is measured in square meters in Europe, it is in square feet in the USA. As well, there is a production item that is measured in meters in Europe and feet in USA. And while we don’t sell anything in volume, I just added gallons to liter and miles to km for the sake of using the whole upper row and be prepared for my next trip to the USA.
The criteria used is the same: press the function key to translate the value TO international system; press shift-function key when translating FROM international system.
1 LBL “EXCHN”
2 “Lb ft 2 G Mi”
5 LBL A
6 RCL 29
9 LBL a
10 RCL 29
13 LBL B
14 RCL 30
17 LBL b
18 RCL 30
21 LBL C
22 RCL 30
26 LBL c
27 RCL 30
31 LBL D
32 RCL 31
35 LBL d
36 RCL 31
39 LBL E
40 RCL 32
43 LBL e
44 RCL 32
Of course, we use one register less than in the previous program, because we only need one for feet and square feet!
I assign it to a shifted key in the user manual. If I ever don’t remember where a conversion was, just press that shifted key again.
Despite its simplicity, it is very convenient to perform fast translations - actually faster than the HP48 family of calculators using their unit menu (there is far more navigation to reach the page where you can actually perform conversions. Let’s not talk about the prime in RPN mode!). And in my job, I can use it several times per day.
I have received a mail from the designer of the circuit board of the HP-41CL (Monte Dalrymple), where he tells me that he has run out of units in his last production batch. He will only restart production in case there is enough interest on it. So, if you were planning to buy one, you're out of luck for the time being.
However, you can try to make a free reservation, just by sending an email to firstname.lastname@example.org, so that I can forward to monte together with other requests ( I have already three of them)
Back at their heyday, there were those that bought the HP 41c because it was the ultimate calculator, only to discover that the cheaper HP 15c had many more functions, and more conveniently located in the keyboard. Some things that the plain HP 41c did not have:
-extended factorial (gamma function)
The user of the hp41c could lie to himself “I can have all that if I buy the right modules”, but that would be an enormous money outlay. It must be said that the advantage module provided most of that missing functionality, but it was never as well integrated as it was on the 15c.
both competitors face to face. Forgive the picture quality!
For example, the complete 4-level complex stack in the 15c; or how well integrated were the matrix functions and the “user” mode to automatically change the pointer for matrix data entry; or the clever use of the permutations and combinations keys for matrix transformations. It really was a clever and elegant device, and still is: more than 25.000 units of the new version have been sold since September 2011.
The only two things where the hp41c always got the upper hand was in alpha capabilities and connectivity. (In fact, it can be argued that it has never been bettered in that area, the USB connection of the 50g family being a poor shadow of the many modules and printers that the HP 41c could drive).
30 years later, the HP 41c user got vindicated - finally. With the “CL” module, you have access to all the functions ever created for the HP 41c in the different modules - all at the same time.
My preferred current set-up (that is good for my work and my hobbies at the same time) is Advantage pack, Sandmath module (latest version) and HP 41Z module (the Z module has a much better complex support than the advantage pac, in my humble opinion - thanks Angel Martín!). With it, I can say I have let the HP15c behind. But it has taken ages and effort!
I go on playing with my HP 41cl. I was today making use of the different functions of the Sandmath module. (For the time being, I have entered the advantage PAC and the Sandmath module only. I have been using the advantage PAC for a long time and I know what’s in it; but the Sandmath is completely new for me)
In my ignorance, and having entered the latest Sandmath version, I did not read that I needed to install first the Library #4. That took me some time to find out. Once I sorted it out, I started using the number theory functions.
My elder son (9) is now learning how to factor a number in prime factors. It was nice to teach him the PRIME? and PFCT functions, so he sees that calcs have other uses apart from mere number crunching. He wanted to take it to class! He will be able to do the minimum common multiple and maximum common divisor too- that’s for next term though.
I have not made a speed comparison between the HP 15c and the HP 41cl. I will probably do it this week end (I have already ported all my 15c programs to the 41cl. I was able to make some improvements, using the additional functions of the ’cl). The more time consuming is my implementation of the IRR, using the advantage pac’s SOLVE function. For a 10 year calculation, it was taking a couple of minutes with the original calculator, and 5-10 seconds with the new one. Let’s see.
(For the to-do list: I want to browse through the multiple modules, to see which programs may be of use for me or my son. Incidentally, I will be reminded of how the world has progressed since the 41c launch.for example,the astro module tells the situation of a number of astronomy objects; same tasks can be achieved with one of the multiple apps for iPad, in graphical form, faster and more conveniently. Sorry for the digression)