Histogram analysis provides the data to create a histogram graph, which shows the distribution of continuous numeric values in one or more columns.
You can apply Histogram analysis to columns of any numeric type, including date types.
Histogram analysis is also called binning, because it counts the occurrence of values in a series of numeric ranges called bins. The histogram function in the Analytics Library provides several ways to define bins and supports multidimensional binning, overlaying categorical data, and the calculating numeric statistics within bins.
- The number of bins of equal size
- The bin widths
- The approximate number of equally populated bins
- The bin boundaries
To show its distribution, Histogram analysis separates the data by bin number and give counts and percentages over the requested rows. Percentages always sum to 100%.
- Subtotals within each bin of the count, percentage within the bin, and percentage overall for each value or combination of values of one or more overlaid columns.
- Simple statistics for a binned column or another column of numeric or date type within the table, providing the minimum, maximum, mean, and standard deviation.
For a date column, the standard deviation is in days.
To further reduce the range of bins or the number of rows to bin, use a WHERE clause.