# CompareHistogram3D

The CompareHistogram3D function Functions are tools that are available in Spreadsheet for processing and analyzing acquisitions or other results. You can add functions to your Spreadsheet job to create tool chains and produce results for specific applications. is used to compare two 3D histograms (existing in the spreadsheet as Histogram3D structures) in terms of their distribution of frequencies. When using the function, consider the following factors:

- To make sense of the comparison, Cognex recommends to compare histograms with similar configuration parameters (such as similar Bin and Subsample Sizes, or similar Minimum and Maximum values). Otherwise, the comparison percentage returned by the function will not reflect the similarity of the two object surfaces associated with the compared histograms.

- Regardless of the configured Bin Size, the number of bins must be the same in the compared histograms. If the number of bins are different, the function returns the Different Number of Bins error message.