Need to strip and split a value

1

I have a column storing GPS coordinates in the following format [40.79087194723902, -65.29992030480717]. I would like to remove the []'s and split the values into a separate lat/long column to allow grafana to properly display them. I have been attempting to use the strings and the map function but I am not able to get the desired results. I don’t see documentation on the return function and i’m not able to figure out how to convert it to the documented with functionality. Any assistance is appreciated. Below is the flux code I am attempting:

import "strings"
from(bucket: "xxxx")
  |> range(start: v.timeRangeStart, stop: v.timeRangeStop)
  |> filter(fn: (r) => r["friendly_name"] == "DeviceName")
  |> filter(fn: (r) => r["_field"] == "location_str")
  |> keep(columns: ["_time", "_value", "_field"])
  |> map(fn: (r) => {
    clean = strings.replace(v: r._value, t: "[", u: "", i: 2)
    final = strings.replace(v: clean, t: "]", u: "", i: 2)
    parts = strings.split(v: final, t: ", ")
    return { time: r["_time"], lat: float(v: parts[0]), lon: float(v: parts[1])}
  })
2

I’ll do 3 maps. , the above code will return

clean = “40.79087194723902, -65.29992030480717]”
finall = “[40.79087194723902, -65.29992030480717”
parts[0] = “[40.79087194723902”
parts[1] = -65.29992030480717]"

All the changes that you do inside the map are not applied to the current record, if you want to “chain” the changes you must do it in different map functions.

You could also build a custom function and do it all at once, but unless you have a LOT of data that isn’t more performant than the 4 maps followed one by the other.

import "strings"
from(bucket: "xxxx")
  |> range(start: v.timeRangeStart, stop: v.timeRangeStop)
  |> filter(fn: (r) => r["friendly_name"] == "DeviceName")
  |> filter(fn: (r) => r["_field"] == "location_str")
  |> keep(columns: ["_time", "_value", "_field"])
    |> map(fn: (r) => ({r with _value: strings.replaceAll(v: r._value, t: "[", u: "")}))
    |> map(fn: (r) => ({r with _value: strings.replaceAll(v: r._value, t: "]", u: "")}))
    |> map(fn: (r) => ({r with _value: strings.replaceAll(v: r._value, t: " ", u: "")}))  //I think you also need to remove the space
    |> map(fn: (r) => ({ _time: r._time,  lat: float(v: strings.split(v: r._value, t:",")[0]), long: float(v: strings.split(v: r._value, t:",")[1]) }))

|> yield()