Remove nulls option

[richardfogaca]

Remove Null Values in Timeseries Charts

Contribution Summary

Added a new control option removeNullValues to Timeseries charts that allows users to control how null values are handled in their visualizations. When enabled, lines will connect across null values instead of breaking at those points. The demo has been implemented in the Line chart type but can be extended to Bar and Mixed charts as well.

How It Works

The removeNullValues control is implemented as a checkbox in the Chart Options section of the control panel. When enabled, it sets connectNulls: true in the ECharts configuration for line series. This tells ECharts to connect data points across null values, creating a continuous line even when there are gaps in the data.

The implementation consists of two parts:

1. A new control in the control panel that allows users to toggle the behavior
2. Logic in transformProps.ts that applies the connectNulls setting to the chart configuration

Screenshot

Before

After

Control

Fork with working prototype

The implementation is available in this fork

Chart containing null data

remove nulls.zip

Why This Matters

Handling null values effectively is crucial for data visualization, especially in time series data where gaps can occur due to various reasons (missing data, irregular sampling, etc.). This improvement:

• Gives users more control over how their data is visualized
• Improves readability of charts with missing data points
• Help with cases where showing gaps in data would be misleading
• Is helpful to maintain visual continuity in trend analysis

[rusackas]

I'm all for it! The only thing I'd note to consider is that the Advanced Analytics section has the zero-imputation infill rule. They're somewhat cognitively related, so I can't help but wonder if they should live together, i.e. a "Null values display" control with options for "remove" "treat as 0" or... I guess "default treatment" if that makes sense?

[richardfogaca]

Right, that makes sense, I like the idea of giving more options @rusackas :)