R How to use which() with floating point values?

Question

I have run into the same problem as described at R which () function returns integer(0)

price = seq(4,7, by=0.0025)
allPrices = as.data.frame(price)
lookupP         


        

Answer 1

You could also try rounding the prices in your data frame to 4 decimal places:

which(round(allPrices$price, digits=4) == lookupPrice)
[1] 425

After rounding to 4 places, the precision of the lookupPrice and your data frame of prices should match.

Demo