pressure normalization of BMP180

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Hello all,
i like to have a normalization of the pressure value of the BMP180. Formula is:

pressure / pow(1.0 - altitude/44330.0, 5.255)

How do I do this with a rule and variable?? Especially with the complex formula?

Thanks

It will be possible with the next release (which will be available shortly).

Here is a proof of concept:

"variables": [
    {
      "name": "pressure",
      "value": 1024
    },
    {
      "name": "altitude",
      "value": 500
    },
    {
      "name": "normalizedPressure",
      "expression": "$pressure/pow(1.0-$altitude/44330.0,5.255)"
    }
  ]

Nice to read

@temp released pimatic@0.9.35

I linke to use this Formula

  'pressure*(1-((0.0065*altitude)/(21+0.0065*altitude+237.15)))**(-5.257)'

because it is more accurate but it always display expression error…
Why? Whats wrong?

@temp said in pressure normalization of BMP180:

**

What is **? pow()?

@mwittig said in pressure normalization of BMP180:

@temp said in pressure normalization of BMP180:

**

What is **? pow()?

Yes, See also keisan.Casio.com/exec/system/1224575267

@temp The following works for me, but I am not sure this what is intended:

$pressure*pow((1-((0.0065*$altitude)/(21+0.0065*$altitude+237.15))),-5.257)

The result is 1093 dot something for the values I had in the previous example

@temp said in pressure normalization of BMP180:

237.15

I think think this should be 273,15 for 0 deg C

EDIT: Just checked my result against the online calc which looks OK. Corrected expression:

$pressure*pow((1-((0.0065*$altitude)/(21+0.0065*$altitude+273.15))),-5.257)

@mwittig thanks