Compute Dirty Area (Data Management)
Summary
Identifies an area within a mosaic dataset that has changed since a specified point in time.
Usage
-
This tool constructs a polygon that defines regions containing one or more mosaic dataset items that have been modified since a specified point in time.
This allows tools and applications that depend on the mosaic dataset for the construction of derived products, such as cache, to perform partial updates since the last time the derived products were synchronized with the mosaic dataset.
-
The date and time parameter can be specified in one of two ways:
- XML time sting
- Non-XML string
A valid XML time string must be in one of the following formats:
- YYYY-MM-DDThh:mm:ss
- YYYY-MM-DDThh:mm:ss.ssssZ
- YYYY-MM-DDThh:mm:ss.ssss-00:00
- YYYY-MM-DDThh:mm:ss+00:00
- YYYY
- YYYY-MM
- YYYY-MM-DD
- YYYY-MM-DDZ
- YYYY-MM-DDThh
- YYYY-MM-DDThhZ
- YYYY-MM-DDThh:mm
- YYYY-MM-DDThh:mmZ
- YYYY-MM-DDThh:mm:ss
- YYYY-MM-DDThh:mm:ssZ
The last possible part of the XML time strings is the time zone. The time zones specified with a Z refers to Zulu Time, or Greenwich Mean Time. You can also specify a time zone by using the positive or negative hours from Zulu Time. If you do not specify a time zone, then the local time zone will be used.
Valid Non-XML time strings can take on any format shown below:
- YYYY/MM/DD hh:mm:ss.s
- YYYY/MM/DD hh:mm:ss
- YYYY/MM/DD hh:mm
- YYYY/MM/DD hh
- YYYY/MM
- YYYY-MM-DDhhmmss.s
- YYYY-MM-DDhhmmss
- YYYY-MM-DDhhmm
- YYYY-MM-DDhh
- YYYY-MM-DD
- YYYY-MM
- YYYYMMDDhhmmss.s
- YYYYMMDDhhmmss
- YYYYMMDDhhmm
- YYYYMMDDhh
- YYYYMMDD
- YYYYMM
- YYYY
Syntax
Parameter | Explanation | Data Type |
in_mosaic_dataset |
The input mosaic dataset. | Mosaic Layer |
where_clause (Optional) |
An optional SQL query that can be specified to only process a specific subset of data. | SQL Expression |
timestamp |
Specify a date and time. All mosaic items modified after this date will be used to compute the dirty area. Currently, there are two types of date formats supported:
For more information about the formatting of the time string, refer to the Usage Tips. | String |
out_feature_class |
The output feature class where the dirty area polygons will be created. | Feature Class |
Code Sample
A Python sample for ComputeDirtyArea.
import arcpy
arcpy.ComputeDirtyArea_management("c:/workspace/fgdb.gdb/md", "#",
"2010-01-12T18:00:00.00-08:00", "dirtyarea.shp")
A Python script sample for ComputeDirtyArea.
##===========================
##Compute Dirty Area
##Usage: ComputeDirtyArea_management in_mosaic_dataset {where_clause} timestamp
## out_feature_class
try:
import arcpy
arcpy.env.workspace = "c:/workspace"
# Find the area changed after 6:00pm Jan 12th 2010
arcpy.ComputeDirtyArea_management("fgdb.gdb/md", "#", "2010-01-12T18:00:00.00-08:00", "dirtyarea.shp")
except:
print "Compute Dirty Area example failed."
print arcpy.GetMessages()