topic Calculation help in ArcGIS Survey123 Questions

Calculation help

DanielSenner1 — Wed, 27 May 2020 19:02:52 GMT

Good Afternoon I am building a Water Quality field data sheet and I am hoping someone can help me out. Our water Quality crews go out and take up to 4 but not always 4 could be 3,2,or 1 measurements. After taking the measurements they perform a calculation to determine if the measurements are within 10% of each other. The calculation I have come up with is below. I am wondering how if there is a way to make it so the value returned is always positive. For example is the first measurement is 5.7 and the second is 6.2 the value returned is -8.403361344537814. I would like it to be returned as a positive number. I am also wondering if there is a way to control the number of decimal places that are returned.

(${secchi_depth} - ${secchi_depth_a}) div ((${secchi_depth} + ${secchi_depth_a}) div 2) *100

Thanks

Dan Senner

Re: Calculation help

KatherineZybko — Fri, 19 Jun 2020 20:22:35 GMT

There doesn't seem to be support for an absolute value function, so I've gotten around that by taking the second power and then the square-root so that it is always positive. (sqrt(pow((YOUR_FORMULA),2))

To control the decimal places use round(sqrt(pow((YOUR_FORMULA),2)),3) -in this case it's rounding it to 3 decimal places.

This page should be a helpful reference:

Formulas—Survey123 for ArcGIS | Documentation

Re: Calculation help

DanielSenner1 — Mon, 29 Jun 2020 20:09:35 GMT

Hi Katherine, thank you for the above recommendation. When I tried to use this example round(sqrt(pow((YOUR_FORMULA),2)),3) I keep getting unbalanced brackets and I cannot seem to figure out what I am doing wrong. I put my formula in from above where you say to put it but no luck. Any additional help or guidance with this would be appreciated.

Thanks

Dan

Re: Calculation help

DougBrowning — Mon, 29 Jun 2020 20:55:56 GMT

I did mine with an if instead.

from a repeat of shots

if(sum(${ElevationChange1})>0, sum(${ElevationChange1}), sum(${ElevationChange1}) * -1)

then compare across passes

100* ((${TotalElevationChangePass1} - ${TotalElevationChangePass2}) div ${TotalElevationChangePass1})

Again the negative in a hidden field just to make it easier to read

if(${SumCalc} > 0, round(${SumCalc},1), round(${SumCalc}*-1,1))

Then I have a note

Pass 3 is needed with a relevant of ${SumCompare} > 10 " Pass 1 and Pass 2 are not within 10%"

Seems to be working so far.

Hope that helps.