Mathematical calculation

[Acetronics2]

Hi, Amindzo

Important questions here are how precise and how accurate does your result need to be? (There is a difference between precision and accuracy.)

As the sensor is given for a basical 2% RH precision .... do you think all those intellectual self-indulgence calculation mean anything ???

certainly not.

just consider your result is "inside" those limits.

Just for laughing : which reference and how many points will you use to calibrate your sensor ??? ( good question, no ??? )

Alain ( Thermics and Thermodynamics Engineer ... BTW.)

[RussMartin]

Hi, Amindzo

As the sensor is given for a basical 2% RH precision .... do you think all those intellectual self-indulgence calculation mean anything ???

certainly not.

just consider your result is "inside" those limits.

Just for laughing : which reference and how many points will you use to calibrate your sensor ??? ( good question, no ??? )

Alain ( Thermics and Thermodynamics Engineer ... BTW.)

The document Alain refers to specifies accuracy, not precision. Accurate data may be precise or imprecise. Inaccurate data may also be precise or imprecise.

I prefer imprecision of accurate data to precision of inaccurate data. Someone who has used both a slide rule and an electronic calculator feels this intuitively, in his gut.

Of course, what we all want is both accuracy and precision. That's why God invented calibration and told engineers to do it.

amindzo, I'm showing you ways to do the calculations; Alain is telling you you don't need them. He may be right . . . but you still have to convert the raw SOrh into %RH, and the formulas will help you do that.

I'm also obliged to note that the document to which Alain refers is 6 years out of date.

[Acetronics2]

Hi, Russ

You're right; In French , Accuracy ... is told "precision" ... so, I sometmes mix the words !!!

I see we have the same readings ... lol !

BTW, I have found some nice sliding rules in the ex Communist part of the world ... I just love to use it : always reminds me what's necessary for life.


one interesting tool for such work is this one :

http://curveexpert.webhop.net


Helps a lot for decent linearizations ...

Alain

[RussMartin]

My apologies, Alain. I have no French and do not know how different words and concepts translate. I help amindzo to find the calculations he needs, and to learn which ones he needs.

In my youth, I learned Hebrew; Latin in high school; and Greek at university. Not much of that helps you or me or amindzo today!

The very first slide rule I used, in 1963, was this one:

http://foraker.research.att.com/~dav...tt/n1010es.jpg

[amindzo]

thank you everybody,i think it's better to use the second method in application note,temperature is very important for me but humidity is not as important as temperature so i think i should use second method.

[Acetronics2]

Timeo Danaos et Dona Ferentes ...

cheers

Alain

[RussMartin]

thank you everybody,i think it's better to use the second method in application note,temperature is very important for me but humidity is not as important as temperature so i think i should use second method.

If you use 12-bit data for SOrh, the first method in the application note is a better choice. The second method is easily implemented for 8-bit SOrh.