Tolerance (Coverage)

Summary

Sets a coverage's tolerances.

Learn more about how Tolerance works

Usage

• A Tolerance Value of zero will not be accepted for the following options: FUZZY, EDIT, NODESNAP, WEED, GRAIN, and SNAP.

• If no Tolerance Type is specified, the default type is FUZZY.

• To see which tolerances have been set and which are Verified, open the Coverage Properties page and go to the Tolerances tab. To do this, right-click the coverage name in the Catalog window or ArcCatalog and click Properties.

• Only one tolerance is set for each execution of this tool.

• Unverified tolerances cannot be verified with this tool. However, if you are using the tool to change existing tolerances to a smaller value, verified tolerances will remain verified.

Syntax

Tolerance_arc (in_cover, {tolerance_type}, {tolerance_value})

Parameter	Explanation	Data Type
in_cover	The coverage for which tolerances will be set.	Coverage
tolerance_type (Optional)	The type of tolerance to be set. FUZZY —Sets the Input Coverage's fuzzy tolerance to the value specified in the Tolerance Value. This is the default option. DANGLE —Sets the Input Coverage's dangle length to the value specified in the Tolerance Value. TIC_MATCH —Sets the tic match tolerance to the value specified in the Tolerance Value. EDIT —Sets the Input Coverage's edit distance to the value specified in the Tolerance Value. NODESNAP —Sets the Input Coverage's node snap distance to the value specified in the Tolerance Value. WEED —Sets the weed tolerance to the value specified in the Tolerance Value. GRAIN —Sets the grain tolerance to the value specified in the Tolerance Value. SNAP —Sets the Input Coverage's general snapping distance to the value specified in the Tolerance Value.	String
tolerance_value (Optional)	The value to be set for the selected option's tolerance. A Tolerance Value of zero will not be accepted for the following options: FUZZY, EDIT, NODESNAP, WEED, GRAIN, and SNAP.	Double

Code Sample

Tolerance stand-alone script

The following stand-alone script demonstrates how to use the Tolerance tool. The script uses Describe to check the tolerances on all the coverages in a workspace. If any don't match a predetermined standard, it uses the Tolerance tool to update them.

# Name: Tolerance_Example.py
# Description: Checks/updates tolerances on all coverages in a workspace.
# Requirements: ArcInfo Workstation

# Import system modules
import arcpy
from arcpy import env

# Set environment settings
env.workspace = "C:/data"

# set the tolerance standards
fuzzyValue      =    1.0
dangleValue     =    0.0
tic_matchValue  =    0.0
editValue       =  100.0
nodesnapValue   =   10.0
weedValue       =   10.0
grainValue      =   10.0
snapValue       =   10.0

coverageList = arcpy.ListDatasets("*", "coverage")

for cov in coverageList:
    desc = arcpy.Describe(cov)

    if desc.tolerances.fuzzy <> fuzzyValue:
        arcpy.Tolerance_arc(cov, "fuzzy", fuzzyValue)

    if desc.tolerances.dangle <> dangleValue:
        arcpy.Tolerance_arc(cov, "dangle", dangleValue)

    if desc.tolerances.ticmatch <> tic_matchValue:
        arcpy.Tolerance_arc(cov, "tic_match", tic_matchValue)            

    if desc.tolerances.edit <> editValue:
        arcpy.Tolerance_arc(cov, "edit", editValue)            

    if desc.tolerances.nodesnap <> nodesnapValue:
        arcpy.Tolerance_arc(cov, "nodesnap", nodesnapValue)           

    if desc.tolerances.weed <> weedValue:
        arcpy.Tolerance_arc(cov, "weed", weedValue)            

    if desc.tolerances.grain <> grainValue:
        arcpy.Tolerance_arc(cov, "grain", grainValue)            

    if desc.tolerances.snap <> snapValue:
        arcpy.Tolerance_arc(cov, "snap", snapValue)

Environments

Current Workspace, Level Of Comparison Between Projection Files, Precision For Derived Coverages, Precision For New Coverages, Scratch Workspace

Licensing Information

ArcGIS for Desktop Basic: No

ArcGIS for Desktop Standard: No

ArcGIS for Desktop Advanced: Requires ArcInfo Workstation installed