Is it possible to get isochrones from R5?

[EvandroStk9]

Hello everyone,

I'm trying to get isochrones from r5r outputs. I've seen this tutorial here on the Porto Alegre Data. However, I have some doubts on how could I get an isochrone of an specific trip duration from an specific point of interest.

Is it possible to get isochrones directly from a R5 call? Or is it mandatory to get a result from a grid settled up by the user in a travel time matrix and then operate an interpolation procedure? Or, at least, is it possible to retrieve the smooth polygon created by the geom_contour_filled as an sf or an dataframe object?

Thanks!

[rafapereirabr]

Hi @EvandroStk9 . This issue is related to #123 . We have developed this isochrone() function. You can use it as a separate function, but it has not been implemented in r5r yet. Please let us know if you find any issues in this function or if yuo have any suggestions on how to improve it.

[EvandroStk9]

Thank you for the quick and kind answer @rafapereirabr. I tried on using the function and worked beautifully.

I will use it more and I'll let you know of any other doubts or possible improvements. Congratulations for this amazing r5r project!

[ichsan2895]

Tested it, so far is good despite a little bit slow.
Maybe reduce sample size in here, it will be faster

r5r/r-package/tests/tests_rafa/isochrone.R

Line 105 in 6c85636

sample_size <- ifelse(nrow(destinations) < 10000, 1, .33) #

[rafapereirabr]

Hi Hi @ichsan2895 . Please read this answer from the dialogue above.

Hi @EvandroStk9 . This issue is related to #123 . We have developed this isochrone() function. You can use it as a separate function, but it has not been implemented in r5r yet. Please let us know if you find any issues in this function or if yuo have any suggestions on how to improve it.

[ichsan2895]

Hi Hi @ichsan2895 . Please read this answer from the dialogue above.

Hi @EvandroStk9 . This issue is related to #123 . We have developed this isochrone() function. You can use it as a separate function, but it has not been implemented in r5r yet. Please let us know if you find any issues in this function or if yuo have any suggestions on how to improve it.

Hello, thanks for that information, I already tested it already and it works :)
My suggestion on how improve it, we can specify the sample size from isochrone function. I think... The lower it is, it will be faster despite reducing the accuracy of detail.

[rafapereirabr]

Ah, sure. Yes, we can add a sample parameter so that the user can set the sample size with the number of nodes/destinations to query.

[rafapereirabr]

New isochrone function added to dev version in #7f50df1.

[rafapereirabr]

We'll continue the discussion of an isochrone function in issue #123.