Histogram from a graphical selection on a string field-symbolized raster displays incorrectly

Description

This problem is addressed in ArcGIS 8.1 Service Pack 1. See the Related Information section to download this pack.

Use the drawing tools to draw a graphic over a portion of a raster layer that is symbolized using a string field. The histogram produced by clicking the Histogram tool of ArcGIS Spatial Analyst gives incorrect results.

Cause

This is a known issue with ArcGIS 8.1.

Solution or Workaround

1. Use the Value field to symbolize the data.
2. Do a graphical selection.
3. Click the Histogram tool.