Put into Library

[user1520]

I’ll admit - Hobbiest, just getting started with making my own apps/drivers (which I find fun).

Today I decided to look into this “Library Code”: I don’t find much on it so I thought I would add a comment to help other hobbiest in their adventure. I have a couple of Apps and one Driver that use a function to calculate dew point. Today I learned that I can have that function in one location instead of in each location I need it. This would have been fantastic during the development of that function so I wouldn’t need to change it in multiple locations as I found errors.

Code that was in 3 different locations:

def dewpt(temp,humid) {
    double lnPws
    double Pws
    double Pw
    double lnPw
    
    C1=-10214.165
    C2=-4.8932428
    C3=-0.005376579
    C4= 0.000000192024
    C5= 0.000000000355758
    C6= -0.0000000000000903447
    C7=4.1635019
    C8=-10440.397
    C9=-11.29465
    C10=-0.027022355
    C11=1.28904e-5
    C12=-2.47807e-9
    C13=6.5459673
    ln=0.4342944819
    Tr=459.67+temp
    if (temp < 32) {
        lnPws=C1/Tr + C2 + C3*Tr + C4*Tr**2 + C5*Tr**3 + C6*Tr**4 + C7*Math.log(Tr)
    } else {
        lnPws= C8/Tr + C9 + C10*Tr + C11*Tr**2 + C12*Tr**3 + Math.log(Tr)*C13
    }
    Pws= Math.exp(lnPws)
    Pw=humid*Pws/100
    lnPw=Math.log(Pw)
    if (temp < 32) {
        Td=(90.12+26.412*lnPw+0.8927*lnPw**2).round(2)
     } else {
        Td=(100.45+33.193*lnPw+2.319*lnPw*lnPw+0.17074*lnPw**3+1.2063*Pw**0.1984).round(2)
     }

    return Td
}

As a Library Code I moved this code from each of those locations to a library with this added prior to the code:

/******************************************************************************\    
 *              Dew Point Calculation Funcion                                 *
 *
 *         to use call the function with #include ERA6515.dewpoint
 *                                                                #include [namespace.name]
 *
 *         then in the app / driver use it by:
 *         double dpTemperature = dewpt(temperature,relativeHumidity)
 *         
 *         temperture and relativeHumidity are float or larger real numbers
 *         the function returns a double real number
 *
 *
 *  2023 No Rights Reserved
 *  Kokopelli Home Automation  (eric albright)
 *
 ******************************************************************************\
*/

library (
  author: "Kokopelli Home Automation",
  category: "function",
  description: "Dew point calculation",
  name: "dewpoint",
  namespace: "ERA6515",
  documentationLink: "n/a"
)

AND ADDED this code to the Apps and Driver that was using it:

#include ERA6515.dewpoint

If I made mistakes in it I would like to know so I can keep improving.

[bertabcd1234]

That looks right and also seems to all be documented here:

Library Defintion

[kkossev]

Remembering the ‘DLL hell’ from the past, I am still cautious using libraries in HE… But as the common code in my drivers becomes more and more huge part of the different devices drivers, seems like there is no other way to go.