`NaN`s and `infinity`s are displaying as null

Context

NaNs and ±Infinitys (possible float values in PostgreSQL) are displayed as null values, leading to problems with summaries (e.g., max(column) will strangely say null is the largest value of a dataset). Even further, they cause the widgets to break.

Steps to Reproduce

1. Import a dataset (which is a CSV but GitHub won’t let me do CSVs) with NaNs and Infinitys: inf-nan-values.txt
2. Change the column type of column val to ‘number’ in the Builder
3. Observe that the val column has values 1.2, null, and null.
4. Run this query to see if those values are actually null-valued: SELECT val is null FROM inf_nan_values
5. Observe that the results are all false, indicating that the values are not null valued.
6. Casting val to text produces infinity and NaN.
7. Calculate the max of the dataset produces null, but casting to text gives NaN again.
8. Create a widget on the column val and observe that the widget does not work.

Current Result

Infinity and NaN are shown as Null when they are actually not and produces different information when used in calculations. These values break the widgets.

Expected result

The values of infinity and NaN are displayed in the builder what they really are to avoid confusion. These values should also not break the widgets, but the user should be able to remove these values easily so that the widgets can work as expected. For example, a broken widget could say ‘Cannot make widget because column has values of Infinity’.

Browser and version

Chrome 58.0.3029.110 (64-bit), macOS 10.12.4

.carto file

None, but this ‘csv’: inf-nan-values.txt

Additional info

Information can be displayed to communicate that there are NaNs and Infinitys in the dataset, and that they are removed when constructing the widgets. NumPy has very good behavior for dealing with these two values.

[jgoizueta]

Acceptance plan:

• Install the branches of SQL-API & Windshaft Cartodb in a staging dedicated server
• Prepare a datasets containing FLOAT & FLOAT8 columns with Infinities & NANs and another NUMERIC columns with some NANs. Duplicate the dataset and create overviews for the copy witth CDB_CreateOverviews (the dataset well need enough rows for the overviews to be populated)
• Create a map with Builder and try all widget types on both tables with the three numerical columns; check widgets run without errors and results are correct (infinities ignored for min/max ranges, etc.)

[jgoizueta]

I’m moving this to deploy, since the acceptance tests are successful regarding the fixes done here to SQL-API and WIndshaft-Cartodb and having this in production is a big improvement over the current situation (where widgets break in the presence of NaNs, etc).

The issues revealed during acceptace affecting various CARTO components can be handled independently in separate tickets.