I always like to do variables and then I can test each section easily if needed. Using just part of your Excel formula as example. Not saying math is right/wrong below but using as an example to show capabilities with variables.
var number a=((([Some field1]+459.67)*(5/9));
var number b=(6.67956-(1002.711/$a-25.215)^^10; //note: you can use previous variable in subsequent variables
$a //will show just 'a' variable
//$b //would show 'b' variable
//←rems/comments out a statement
Hopefully you get the idea.
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Greg
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