Interactive data QC

In this document

You will learn how to manually flag inconsistent values in your dataset.

Interactive data quality check (QC) tools provide an additional manual flagging of data inconsistencies that were missed by the automated QC checks. Use them to visually inspect the dataset and manually flag remaining inconsistencies to polish your dataset further.

Interactive data QC is offered via two nearly identical tools - Interactive QC and Interactive QC advanced. The main difference between the two is in the way the data are displayed. The former offers a time series chart only (if that is all you need for analysis), and the latter provides additional sun path and heat map for better data interpretation. For the purpose of this guide, we will use the advanced tool to present information that is available for both.

Key points to remember:
Interactive data QC checks are manual, not automatic. You have to select and flag the data manually.
Take advantage of the keyboard shortcuts for quick navigation when inspecting the data.
Zooming the chart also considers the selected height as well. You can use this advantage when selecting data range with low values which would otherwise appear close to zero in the chart.

Interactive data QC tools

You can open the interactive data QC tools from the main menu via Quality/Interactive QC (Interactive QC advanced) or by using the respective or quick access icons located below the main menu. The window interface offers the following (Interactive QC advanced):

Time series chart: Use it to inspect the data to find unflagged inconsistencies.
Sunpath and heatmap: Additional help in finding the inconsistent data (Interactive QC advanced only)
Parameter selection: Use it to select parameters to show in the charts and which to flag when selected by data selectors.
Flags: List of flags already added to the dataset by automatic QC checks.
Heatmap parameter selector: Choose which parameter to display in the heatmaps.

Flagging the data manually

The manual data flagging process requires close inspection of the data in the time series chart. Use the toolbar controls to help you zoom the chart and select the data to flag, and keyboard shortcuts to navigate the chart effectively.

Use the tool to zoom the chart until you start spotting the inconsistencies.
Alternatively, define the zoom using the date range filter. Click “Apply” to show the range in the time series chart.
Use checkbox to show required parameters in the time series chart. The highlighted icon next to the parameters indicates the parameter will be flagged. You can select one or multiple parameters to flag. Greyed-out flags on displayed parameters can be used as helpers to compare the data, but will not be flagged.
You can zoom further into the data you wish to flag for precise value selection.

Select fags you want to overwrite with a new flag if required. Values flagged as passed (green) are enabled for flagging automatically.
Use any of the data selectors to select values you want to flag.
Selected values will be highlighted.
Choose the flag number you want to apply to selected values. Type the flag number in the field manually or use the icon above to select from available flags. Click “Set” to apply the flags.

Keyboard shortcuts

Use the keyboard shortcuts to speed up your workflow when navigating the data in the chart.

Keyboard shortcut	Action
arrow keys	Moves the chart horizontally by an interval identical to the currently selected range; for example, with a 24-hour selection, the chart shifts by 24 hours. With a 5-day selection, it shifts by 5 days.
arrow keys	Moves the chart vertically (up or down).
A, S, D, W keys	Identical to the arrow keys for left-handed controls.
Ctrl + F	Same as clicking the “Set” button - applies the selected flag to the selection.
CTRL+U	Undo last flagging
Numerical keys	Turn flagging on/off on selected parameters. Same as clicking the flag next to a parameter.
Esc	Unselects the current selection.
R	Enable/disable rectangle data selector
Q	Enable/disable lasso data selector
E	Enable/disable expression data selector

Using a reference dataset and theoretical curves for data comparison

If you have a reference dataset you want to use for the data comparison, you can add it to the plot using the “+ Add data” at the bottom of the columns selection list. Once the dataset is added, you can use it to display its values in the time series chart and compare it with your data. You can remove it anytime using the “- Remove data”.

Additionally, you can compare the solar parameters with theoretical reference curves created specifically for this comparison. These are listed at the bottom of the dataset parameter list with an added “theoretical” expression to the name. For example, you can compare GHI with GHIc-theoretical. These theoretical curves are generated by the system and represent clear sky conditions at the given location.

Additional options and customization

You can customize visualizations if required using the icon to the right. Here, you can decide whether to show/hide the maintenance log, adjust the marker size, style, and colors.

Tip: If you want to go to quality report directly from here, use the “Quality report” button at the bottom-right.

Finishing interactive data QC check

You can periodically save the progress using the “Save” button. Once you are done with the interactive QC data checks, use the “Save final” button to apply the changes and add interactive data QC status to the dataset.