I've another noobie question. I'm hoping to get a 2D matrix/table output for two 1D vector inputs.


20220414 Vectorize Question.sm (53kb) downloaded 13 time(s).

How can this be best done?

Edited by user 14 April 2022 06:09:43(UTC)  | Reason: Cut-n-paste errors...

Thank you so much overlord.

BTW: did you spot my evil(ish) dB:=1 declaration? (no SI units were harmed).

I certainly am wanting to stick to SI units for all the good reasons.

I will work through this to understand it better. My memory of this is that dB really is unitless, so the 'dB' is likely just a placeholder rather than something referencing the base mks units. I'm keen to know if this assumption I've had for a few decades is incorrect.

I'm liking the consistent description position too, thank you. Much better than free floating text.

Thanks Jean,
An important topic on its own: validation and review. So central to good engineering & metrology. Already done too.

One of the reasons I like SMath is measurement units. The continuous units consistency checking is great.

Without it (units ignored or overridden), it is possible to get the correct (or close to it) numeric answer and be fooled.

Part of being a PE is working out what the question actually is, before working out the answer and how the answer is framed.

Units matter, and can't be ignored, or done wrong.

Imperial measurement units are now metric, but just framed wrongly (aka 'stirring bastard').

Edited by user 16 April 2022 11:17:17(UTC)  | Reason: Brackets, standards and units.

The world standard for aircraft speed is SI units:

with knots operating on a 'temporary' exemption.

Two units with the same name, but different meanings are being used by people that need to work together. Ditto for different units for the same thing (height, wind speed, pressure, fuel mass, COG mass calcs, etc). What could possibly go wrong?

Edited by user 16 April 2022 23:02:47(UTC)  | Reason: URL fix

If you don't know units, how to use them, don't have the capability to understand its importance, even you oppose using units, just as like Jean, everything can go wrong.
And yours is another milestone example of that idiocracy.

Good catch Alvaro, thanks.
I use OACI instead and Ralph C. data source.
I checked the document I attached in the Forum long time ago: correct.
Cheers ... Jean.

For me units have 2 purposes:
1. Getting quickly understandable numbers
2. Checking errors (unit consistency)

But sometimes I need to combine unitless numbers with numbers with units. This is when the unit is implicit and I don't want to make the calculations look unnecessary heavy, with units all ober the place, but for some of the inputs (or outputs) I still want units, for clarity... when the standard unit would have too many or too few figures.

This is where Smath is great with the possibility to use any variable as a unit. I even sometimes define units such as "bag" or "bamboo"! And doing that without using an actual "unit" but only a variable, allows to bypass Smath's unit consistency check.

This flexibility is really great. We have "proper" units (in blue) with consistency checking, but we can also have "de facto" units which are just conversion factors (in black), and are optional so they can be used only at places when the standard unit is not convenient, without the need to rewrite everything with units.