Change arguments in classes

Available with Spatial Analyst license.

You may want to change an individual argument to a parameter because you have gained additional information about the phenomena that you were modeling, you want to test alternative scenarios, you want to perform error or sensitivity analysis, or you want to correct an error. The examples below demonstrate how to change a variety of input arguments.

• Learn more about Spatial Analyst classes

Class values or properties

• To change a value of a class object, you can re-create the class.

  neighborhood = NbrCircle(5, "MAP")
  
  # The neighborhood object can be changed from a circle to a rectangle
  neighborhood = NbrRectangle(3, 3, "MAP")

• A single argument can be directly changed by accessing the property that stores the argument in the object.

  >>> neighborhood = NbrCircle(5, "MAP")
  >>> # The following statements change the radius to 7 and the units to CELL
  >>> neighborhood.radius = 7 
  >>> neighborhood.units = "CELL"
  
  >>> print(neighborhood)
  CIRCLE 7 CELL

• A numeric argument stored as a property in an object can be changed algebraically.

  circle = NbrCircle(5, "CELL")
  
  # The following statement changes the radius to 5.5
  circle.radius = circle.radius * 1.1

  You can also use an assignment operator to change the value.

  # The following statement changes the radius to 5.5
  circle.radius *= 1.1

Classes created with Python lists

• You can add elements to the inFeatures list for classes that were created from lists.

  >>> arguments = TopoStream(["features1", "features2"]) 
  
  >>> arguments.inFeatures.append("features3")
  >>> arguments.inFeatures += ["features4", "features5"]
  
  >>> print(arguments.inFeatures)
  ['features1', 'features2', 'features3', 'features4', 'features5']

• You can also delete an element from the input list.

  >>> arguments = TopoStream(["features1", "features2", "features3", "features4", "features5"])
  >>> del arguments.inFeatures[2]
  
  >>> print(arguments.inFeatures)
  ['features1', 'features2', 'features4', 'features5']

• You can change a specific entry in the list.

  >>> arguments = TopoStream(["features1", "features2"]) 
  >>> arguments.inFeatures[1] = "lake2"
  
  >>> print(arguments.inFeatures)
  ['features1', 'lake2']

Classes created with lists within lists

• You can change an entry in a remap table (altering entries within inner lists) for classes that were created from lists within lists.

  >>> remap = RemapValue([[1, 11], [2, 12], [3, 13]])
  
  >>> # Change the newValue 12 in the second reclassification to a 10
  >>> remap.remapTable[1][1] = 10
  
  >>> print(remap.remapTable)
  [[1, 11], [2, 10], [3, 13]]

• An individual entry in a remap table can be changed algebraically.

  remap = RemapRange([[1, 10, 5], [10, 20, 8], [20, 30, 10]])
  
  # The following statement increases the endValue 20 by 5 percent
  remap.remapTable[1][1] *= 1.05 
  
  # Another implementation of increasing an entry by 5 percent
  remap.remapTable[1][1] = remapTable.table[1][1] * 1.05

• You can change an individual row in the remap table (altering entire inner lists).

  >>> remap = RemapValue([[1, 11], [2, 12], [4, 13]])
  
  >>> # Change the second reclassification [2, 12] to [3,10]
  >>> remap.table[1] = [3, 10]
    
  >>> print(remap.remapTable)
  [[1, 11], [3, 10], [4, 13]]

• You can add entries to a remap table (adding an inner list).

  >>> remap = RemapValue([[1, 11], [2, 12], [3, 13]])
  
  >>> # Add a forth reclassification, [4, 14] to the end
  >>> remap.remapTable.append([4, 14]) 
  
  >>> # Another approach for adding a row
  >>> remap.remapTable += [[5, 15]] 
  
  >>> print(remap.remapTable)
  [[1, 11], [2, 12], [3, 13], [4, 14], [5, 15]]

• You can delete entries from a remap table (deleting an inner list).

  >>> remap = RemapValue([[1, 11], [2, 12], [3, 13], [4, 14], [5, 15]])
  
  >>> # Delete the entire second reclassification
  >>> del remap.remapTable[1]
  
  >>> print(remap.remapTable)
  [[1, 11], [3, 13], [4, 14], [5, 15]]

Classes created from a series of classes in a list

• You can change a specific point in the list for a class that was created from a series of classes in a list.

  >>> points = [Point(0, 5), Point(15, 175)]
  
  >>> # Change the X value of the second input to 25
  >>> points[1].X = 25 
  
  >>> print(points)
  [<Point (0.0, 5.0, #, #)>, <Point (25.0, 175.0, #, #)>]