DM42 - 4 programs to do what TI-36X Pro has built-in

[@raimundwildner4169]

I think it is a little bit unfair for the DM42. You only show problems the TI has built in software. If you have a problem with 4 linear equations and 4 unknowns you are lost with the TI but you can quite easily solve it with the DM42.

[@scottcollins7513]

There's no doubt that the DM42 is a great little calculator, but I am surprised by some of the things that are not built-in. The original spirit of the video was not actually intended to be a critique of the DM42, rather, I just wanted to show how I had worked around each of the issues. Thanks for the feedback, Raimund.

[@CoolAccent]

Great video Scott, and thanks for sharing the .raw files too, much appreciated!

[@scottcollins7513]

Glad you found it helpful (including the .raw files). Thanks for taking the time to leave a comment. Enjoy your DM42!

[@jessstuart7495]

I believe there is a lot of value in writing little stack programs for scientific calculators. You aren't limited to just the built-in functions the calculator developers decided to include.

[@scottcollins7513]

AGREE. Definitely takes things to another tier. Thanks for insightful comment, Jess.

[@4034miguel]

Indeed. Considering that the comparison is between a TI from 2004 and a clone of a HP from 1988. It is a nice thing that the 42 demonstrates its worth thanks to its programming capabilities. Very useful programs. Already downloaded. Thanks.

[@irishchocolate3872]

My first programmable calculator was the SR-56 which my mom bought for me in December of 1975. It had 100 program steps and an applications library book. You can still download it on the internet. It sold for $125 which would be probably the equivalent of $600 by today's standards. My TI-36XPRO will basically do all and even more than my old SR-56 did for about $25 and no need to program.

[@scottcollins7513]

Very cool that your mom bought that for you! It is amazing what a $20-25 calculator can do now-a-days -- though they do lack programmability. Thanks for the comment, I.C.

[@corkerydan]

Thanks for the video and access to the programs. Nicely done.

[@scottcollins7513]

Thanks for the kind and encouraging words. Glad you found it helpful or useful on some level. Such a cool little calculator.

[@RicRic-bg8sn]

Thanks for the Raw files and video ;-)

[@scottcollins7513]

Glad to share. Thanks for leaving a comment!

[@MrNoahTall]

Great video showing the programming workaround to the DM42 constraints imposed by the original mandate to adopt Free42. The DM42 is a great machine, and I love mine. My workaround is to simply have the inexpensive TIs (both the 36X Pro and the European 30X Pro).

[@scottcollins7513]

Thanks, "Noah". Yes, the DM42 is a great little machine, and I too have access to an inexpensive scientific calculator should the need arise to do the things covered in this video. Thanks for leaving a comment and enjoy your DM42 (and TI-36X Pro)!

[@wisdomandknowledge9361]

Nice video, thank you for posting it.

[@scottcollins7513]

Appreciate the feedback -- thank you for leaving a comment. It's a cool little calculator.

[@peterwilson7532]

I enjoyed it! 😂

[@scottcollins7513]

Thanks for letting me know. Glad you liked it!

[@Lyndalewinder]

Hi Scott - really useful video but I'm not able to view your RAW files. My Mac says that these files come from an "unknown" developer and won't let me open them. Is there any way you could post them in some other format?

[@scottcollins7513]

It sounds like a setting on the Mac that needs to be tweaked. But, I went ahead and put the same files on my Drive and shared the folder: drive.google.com/drive/folders/1okJL9nak92neYp-vFjCifZyxVDEbhLI-?usp=sharing I also created a zip copy (in dropbox and drive) that includes all the .raw files -- perhaps that will give you a work-around. Hoping this works for you.

[@rockom77]

My DM42 should be here any day now! I can't wait to try it out. I'd say the reason these functions are not built is because the DM42 is running Free42 firmware which simulates the original HP42. The WP43s makes it a little easier. It has sum command but you still need to enter the function either as a program or inline on the stack. I hope the WP43s starts shipping soon!

[@scottcollins7513]

Rocko, I think you'll enjoy the DM42. I really like mine. My comment about the lacking features was from the angle of "the HP 48 of the same time did have these features, so I'm surprised the DM42 did not" -- that said, I realize that they were completely different machines (RPN vs RPL). The DM42 is more approachable, compact, and has a much much better display than the HP 48.

[@TylerSimsMechanical]

Just got my DM42 today. Is it possible to turn a matrix into an RREF matrix?

[@scottcollins7513]

I'm not sure. I kind of doubt it. You can check the forums on museum of hp calculators. Do you truly need RREF or are you just trying to solve multiple linear equations (i.e. solve 4 variables w/ 4 unknowns)?

[@scottcollins7513]

One other comment is that somebody probably wrote a program to find RREF.

[@TylerSimsMechanical]

@@scottcollins7513 I don't truly need RREF. I just prefer to use an augmented matrix to solve systems sometimes because it's quicker to double-check since everything is in a single matrix. I've just been using two matrices, and multiplying the B matrix by the inverse of the A matrix. I know SIMQ works too (alongside your nice xyeq. program).

[@TylerSimsMechanical]

@@scottcollins7513 I'll have a look around. Thanks for the response!

[@scottcollins7513]

@@TylerSimsMechanical Sounds like you know more than I do about how to solve linear eqs! Would be nice if the DM42 had the RREF function. I have an old hp 28S and it also lacks the RREF function. I'm sure there is a program out there that would give you the same RREF result if you wanted to spend the time looking for it.

[@abather11]

Hi sir Let's say I am using free42 app I press 5 inter 8 Then instead of pressing the multiply button i press the division one by mistake. How do I go back to y =5, and x=8?

[@scottcollins7513]

My old hp 28S had an undo feature just for this sort of thing. To my knowledge, the hp 42s does not offer this functionality, unfortunately.

[@thorhilda]

This is where the [LAST X] button is useful, to reverse the operation. [LAST X] [ x ] to undo the division [LAST X] to put back the 8 on the stack