Hello.

I've been following several posts for Q&A for some days about my doubts, but one about Units is not yet solved.

I've been trying to solve a simple problem for air density to practice.
The units always stand in my way and I am interested in how you guys would solve this: ignoring units and not using the built-in constants or make everything converted before handling the problem?

My sheet and the problem I'm trying to get the same results are in the images below.

Is there a way to make the function in a programming line ? Like the other software?

Couldn't get the answers by other's questionings.

Thanks in advance.

Try this.

Barometric formula.sm (9.31 KiB) downloaded 642 time(s).

Thanks!

I'll try it myself and see if it works.

As for the odesolve block it not yet finished. You must use functions like rkfixed() to solve the ODE.

Good to know.

I'll try it.

Thanks

Wrote

Is there a way to make the function in a programming line ? Like the other software?

Just lost my long reply ...
The only possible programming line is the conditional .
NO software can't calculate otherwise than by segment
because Air is not an homogeneous media. So, NO single
formula, NO ODE can represent.
The attached will give you specific kg/m³ up to 85 km geopotential.
Naturally, don't put any units in there. Append unit in result.
Please don't hesitate for more Q & A

Cheers ... Jean

The 3 segments collected page 6/6

Inst_ISA.sm (138.45 KiB) downloaded 605 time(s).

Wrote

The 3 segments collected page 6/6

Maybe there was a typo in the attached document.
Please: check, correct as needed.

Thanks.

I'll study the document.

Wrote

I'll study the document.

The J(x) upper segment was borrowed directly from Mathcad 11.