I currently have a data file that has columns for each day over an 8-month period.

I am seeking of a way to create an interactive CARTO map that displays the change over time. I want to know if there is a way(or even possible) in Cartoframes or CARTO-VL that the animation over time can change by iterating through the date columns.

I know there is a way to display this change over time by making all date columns unique to each geography (polygon). The issue is I have nearly 850 geographies. Even limiting my dataset to 3 months, we are approaching 1 GB of data (due to the geometries of each field needing to be stored). The size won't generate a time series map on any library I've found or import to CARTO.

With the wide format (each date has its own field) the dataset is only 23MB for 8 months of data. I have not seen any examples iterating through columns but I feel there has to be a way (maybe I'm crazy).

Image of column sample:

I'm looking to iterate through each date column I have (1/1, 1/2, 1/3... Each of them associated to their respective polygon

  • Could you share a link to your dataset? If the dataset is private, could you share a dummy sample dataset with the right schema? Oct 9, 2020 at 14:18
  • shared it in the edited post. I want to iterate over 1/1, 1/2, 1/3.....to each day
    – sTonystork
    Oct 9, 2020 at 17:00

1 Answer 1


You would need to melt your dataset in order to transpose your columns into rows. In doing so, your dates will be stored as a new unique field and CARTO VL will be able to iterate throught them. There are two alternatives to achieve this.

a. Pandas' melt function:

df_long = pd.melt(df, id_vars=["id"], var_name="date", value_name="metric")

b. Postgresql pivot query. You can see a working example here.

Finally, I would suggest storing your unique geometries in a master table and join them when needed.

  • Ah yes I've done that already, the only thing is my data is over ~230 consecutive days, so the draw time and storage is quite difficult. I have since converted each polygon to centroids in order to have a visualization. I think the polygons are just too complex, and it seems there is no reproducible example to iterate through each column data field, only melt which just places each date into a record like you metioned
    – sTonystork
    Oct 15, 2020 at 18:46

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