Numerical integration direct from the keyboard?

[John Garza (3665)]

Thanks for the help all.

However, this is one of those things that tends to drive me away from the newer HP calculators for anything other than a novelty. It comes down to simple usability and having an intuitive interface.

I, like the average new user to the Prime, sees CAS, and says 'Computer Algebra System = Symbolic Work' and I do NOT want symbolic integration, so I look elsewhere and do not consider that option. So... I am off chasing the wild geese...!

Then when using Home, I get many syntax errors filling out the param line for int(), and even directly copying the examples (seen by cursoring to the start of int() and hitting 'Help') gives errors. So... if int() is supposedly only valid in CAS, then why is it in the menu I see in Home? It should be at least greyed-out to show it's not a valid option at this time.

Then trying CAS, and selecting int() from the menu, it takes me to an equation editor, where I have to scroll around filling in the params and using lots of keystrokes. And it gives me the expected symbolic solution - which is not the desired result. I need numbers, this is engineering; not a course in calculus.

So, as an experiment, I do not use the menus and try just typing it in spelling out i-n-t...etc. That works! ...but still takes many keystrokes. And uses quotes which is NOT indicated in the help screen examples.

Then going back to the equation editor, I add the decimal point... and that works too! That's probably the best (quickest) solution from my point of view.

Still...load some params on the stack, hit f integrate, and bam! an answer shows up. That would be so much simpler and quicker.

And a cool idea on using the decimal to imply approximate numbers - though I don't recall seeing that in any help screen. Again, a design issue, the huge difference between symbolic and numeric controlled by an obscure decimal point in the param list. Non-intuitive. An extra binary param would have been more clear-cut. But then, it's one of those issues that bites you hard in the beginning, so you are not likely to forget it!

Overall, it seems difficult to actually use numerical integration as a working tool as you can in other HP calculators. In the course of your normal RPN calculations, you may need an integration value, so you get it then return to your work. Not so here. The Prime seems geared to teaching mathematics, and kudos for that. But a workhorse this is not. It's a hayburner with a quirky personality and a nice shiny coat, but I still love it!

-John