Hour filtering and colored rectangle alignment

[matteomerli]

First of all, I want to thank you for developing and maintaining this amazing tool! I’ve been using it occasionally for a few years, and it has been incredibly helpful.

I’ve noticed that when filtering by hour, the colored rectangles start at half-hour intervals, whereas they should align with full-hour intervals, showing the value of the previous hour, according to the convention of EPW files.

Additionally, the filtering option ranges from 0 to 24, with the first value correctly not being used (but unnecessarily present?). Therefore, selecting 1 AM should color the bin from 00:00 to 00:59 AM, 2 AM from 01:00 to 01:59 AM, and so on.

I understand this may be confusing for users who are unfamiliar with weather file conventions, and adding annotations in the tool could help them better understand. For example, it could be helpful to note that when choosing a filter range from 9 AM to 8 PM, it actually returns data from 8 AM to 7:59 PM.

[FedericoTartarini]

Hi @matteomerli,

Thank you for your detailed feedback and for your long-term use of the CBE Clima Tool. We appreciate you taking the time to report these issues. You've raised some excellent points about how we can better align the tool's visualizations with EPW data conventions.

I am now changing the tool and modified as follows, please help me check that the new behaviour is correct.

1. Before, the colored rectangles in the heatmap were centered on the hour marks (e.g., the bin for hour 8 extends from 7.5 to 8.5). This is the default behavior of the plotting library we use. We agree that for EPW data, it would be more intuitive if the bins aligned with the full hour (e.g., 7:01 to 8:00 for the 8 AM data point). Hence, I have shifted the hours in the data frame in the backend by -0.5 so the visualisation now looks as follows. Could you please confirm that this is the expected behaviour?

2. The core issue is that the hour labels in the filter (e.g., "9 AM") don't intuitively match the time period they represent (8:01-9:00) due to the EPW convention. You are suggesting we should clarify this for users. For example, if a user selects a filter range from 9 to 10, we should show only the data between 9:01 and 10:00. I have changed it as follows. Could you please confirm that this is the expected behaviour?

I have already committed these changes, but I can revert them if I did not implement them correctly. Please note that the new version is not live yet. We will publish a new version, which will include this change soon.

@t-kramer we need to check that this issue is not present in the other charts. I, therefore, opened issue #234 and checked that the filtering and visualisations are consistent across all tabs. I believe I fixed that.

[matteomerli]

Hi @FedericoTartarini

Thank you for implementing these adjustments!

Regarding the changes:

1. Shifting the hours by -0.5 so the rectangles align with full-hour intervals looks correct and should match the EPW convention.

2. I agree that the EPW convention is a bit unintuitive since it uses a 1-24 hour format, while most coding contexts use 0-23. I first noticed the issue when selecting “0-2” or “1-2” produced the same result (two bins coloured), because Hour 0 doesn’t actually exist in the EPW. My first thought was that the filter could instead span from 0 to 23 or from 1 to 24. Alternatively, to make the tool more user-friendly, it also makes sense to keep the filter as 0-24, as long as you ensure the selection always covers at least a 1-hour range (preventing users from selecting the same start and end hour, e.g., 9 to 9). I believe this is how you’ve already implemented the change, but I can’t verify it yet.