In this document
You will learn how to work with the Compare analysis tool of the Analyst application and how to examine the data.
The Compare analysis tool in Analyst enables you to compare the values of two selected parameters from your datasets, or one measured parameter with reference values.
Key points to remember:
You can compare two parameters only at one time, not more.
The interface offers several types of visualizations, separated into individual windows, to examine the data in various ways.
Zooming and moving charts is synchronized across all plots in the respective visualizations.
Filters, aggregations, and other options must always be applied using the “Redraw” button.
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.
Compare analysis tool
You can open the Compare tool from the main menu via Analysis/Compare or by using the 
quick access icon located below the main menu.
The interface offers the following:
Visualization windows: Switch between different data representations, charts, and data comparison tools.
The visualizations plot: Various visualizations are displayed here, depending on the selected visualization window.
Parameters to compare: Select reference and estimate parameter to compare their values, with statistics metadata shown below.
Options: Filter the data, use aggregations, filters, and other data comparison tools specific to the selected visualization window.
Redraw: Use this button to apply selected filters, aggregations, and other configurations.
The visualization options
You can customize the charts and configure the visualizations to your requirements. Each data visualization method offers data aggregation and filtering options for better data examination. These are located below the compared parameter statistics window.
Aggregations, Filters, and Flags options are identical for all visualization screens. Additionally, there are visualization-specific options that each window offers for even better customization.
Data aggregation
The datasets are displayed in the charts with their original temporal resolution by default. If you want, you can aggregate it to a bigger one to highlight broader trends and patterns (e.g., 1-minute data to 15-minute data).
To aggregate the data:
Select the desired aggregation in the Aggregation dropdown.
Set the minimum of valid points (in percent) that must surround the aggregated value to display it in the chart. You can leave this on the default.
Click “Redraw” to execute and show aggregated data in the charts.
Filtering options
Take advantage of dedicated filters to filter your data based on your requirements.
You can filter by year/month or exact dates, depending on your preference.
You can apply a time interval to see values only at a particular time period of each day. Additionally, you can include/exclude daytime and nighttime values using the respective checkboxes.
The sun elevation filter is also at your disposal to select a period between certain sun elevation levels.
Tip: Always apply the filters using the “Redraw” button.
Flags filter
An additional Flags filter is provided for you to view values with particular flags only. This can be useful when you need to examine, for example, values that were flagged with the shading flag. Passed values are selected by default - make sure to uncheck them if you do not want to see them in the chart.
Note: Keep in mind that the dataset must contain flags from relevant quality control (QC) checks to use the flag filter.
Select the flagged values you want to display.
Apply filter using the “Redraw” button.
Analyzing your data in the Compare tool
You can analyze your data using the following visualizations:
Scatterplot: Compares the data in scatterplot charts, histograms, and the cumulative distribution function (CDF).
Monthly scatterplot: Compare the data in monthly scatterplots.
Time series: The comparison is visualized in a time series chart, providing an extra chart for the difference values only.
Heatmap: Displays separate heatmap per parameter and an additional difference histogram with customizable visualization settings.
Analytical plots: Offers various additional charts to compare different data attributes.
Scatterplot visualization
The default window when you enter the Compare analysis tool is the Scatterplot window. You can use it to compare the data in scatterplot, histogram, and CDF charts. Additional configuration options to customize the visualization include:
Setting the histogram start value (enable with checkbox first)
Configuring the histogram bin size or number of bins to show
Configuring the number of bins for the CDF chart
Monthly scatterplot visualization
Here, you can examine the data in monthly scatterplot charts. Additional options here allow you to toggle the display of the monthly stats on/off.
Time series comparison visualization
In this window, you can compare the selected parameters in the time series chart and examine the difference in values in the second chart. In the difference chart, the red line represents the zero.
Heatmap parameter comparison
The heatmap visualization offers an insight into the data in the form of heatmaps. First heatmap represents the values of the first parameter, the second heatmap the second. Last heatmap shows the difference between the two.
You can customize the Y-axis of the difference heatmap to focus on and visualize a particular difference range if required. The scale to the right indicates the applied range.
The difference heatmap.
Current scale of the color scheme.
Color scheme settings: Set min/max values to change the way the difference values are displayed.
Analytical plots
The analytical plots offer additional ways to look at your data. It compares the parameter’s metadata, such as sun elevation, declination, or sun azimuth. Use these based on your requirements.
