I am new to Power BI and DAX, so I hope you can help me.
I have two tables without any relationship: Table A contains lat/lng and date of tracked positi
Here's one possible approach:
First, calculate the minimal distance using the Haversine function.
Add this as a calculated column to your Tracked
table.
Nearest =
MINX(Stadiums,
ROUND(2 * 3959 *
ASIN(SQRT(
SIN((Stadiums[Lat] - Tracked[Lat]) * PI()/360)^2 +
COS(Tracked[Lat] * PI()/180) * COS(Stadiums[Lat] * PI()/180) *
SIN((Stadiums[Lon] - Tracked[Lon]) * PI()/360)^2)), 1))
In this formula, 3959
is the radius of the Earth in miles.
We can now match up distances to find the nearest stadium:
Stadium = CALCULATE(MAX(Stadiums[Stadium]),
FILTER(Stadiums,
ROUND(2 * 3959 *
ASIN(SQRT(
SIN((Stadiums[Lat] - Tracked[Lat]) * PI()/360)^2 +
COS(Tracked[Lat] * PI()/180) * COS(Stadiums[Lat] * PI()/180) *
SIN((Stadiums[Lon] - Tracked[Lon]) * PI()/360)^2)), 1)
= Tracked[Nearest]))
Note: I rounded the values to avoid not matching from possible floating point errors. This may or may not be necessary.