Advance Model Builder Features
Advance Features
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Using Lists (also Batching)
Iteration
Feedback
Model Only Tools
Inline Variable Substitution
Preconditions
Feature Set and Record Set
If-then-else logic
In-memory workspace
Integration of model, scripts and external programs
Using Lists
• A variable that contains one or more values is called a list
variable. It is a property of a variable
• When an output list variable is created in a model, you can use
%i% as in-line variable substitution in the output name. %i%
appends the list number at the end of output name.
Using Lists
• The model is now ready to run from within
ModelBuilder. The model will execute for
each input contained in the Input Feature Class
list variable.
Using Lists
• It is my opinion that Lists are best used from
multi-step, but “short” processing.
• Use the %i% to create unique output for each
list “input”. %i% starts at zero (%0%)
Batch Processing
• In ArcGIS batch processing means to execute a single tool multiple times
with different inputs without your intervention.
• In ArcCatalog or ArcToolbox, right-click a tool and click Batch. This will
open the batch window, where you can set up multiple runs for the tool.
When you open the batch window for a tool, one row is automatically
added, ready to accept input. The following example uses the Clip tool.
Batch Processing
• Entering parameters: To enter the parameters for an entire row, double-click the
row header to open the tool's dialog, as shown below. Alternatively, you can rightclick the row header and click Open. Use the dialog to enter one or more of the
parameter values.
Click OK
Iteration
• Iteration or Looping, is to repeat a process
over and over with some degree of automation.
• There are 12 iteration tools in Model Builder.
– For: For iterates over a starting and ending value
by a given value. It works exactly like For in any
scripting/programming language, executing
through a set number of items.
– While: While works exactly like 'while' in any
scripting/programming language, executing
"while" a condition is true.
Iteration
– Iterate Feature Selection: Iterate Feature Selection
tool iterates over features in a feature class.
– Iterate Row Selection: Iterate Row Selection tool
iterates on rows in a table.
– Iterate Field Values: Iterate Field Values tool
iterates over each value in a field.
– Iterate Multivalue: Iterate Multivalue tool takes a
user-specified list of inputs (for example, inputs
from different locations or a subset from a single
location of any single type) and runs the model for
each value.
Iteration
– Iterate Datasets: Iterates over datasets in a Workspace
or Feature Dataset.
– Iterate Feature Classes: Iterate Feature Classes tool
iterates over feature classes in a workspace or feature
Dataset.
– Iterate Files: Iterate Files tool iterates files in a folder.
– Iterate Rasters: Iterate Rasters tool iterates over rasters
in a Workspace or a Raster Catalog.
– Iterate Tables: Iterate Tables tool iterates over tables in
a workspace.
– Iterate Workspaces Iterates over workspaces in a
folder.
Iteration
• Only one iterator can be used per model.
• If an iterator is added to a model, all tools in the
model iterate for each value in the iterator.
• If a model containing an iterator is exported to a
Python script, the script will not include the iteration
logic.
• Using an iterator will set a default value of -1 in
Iteration Options in Model Properties, which simply
means that the model will run for unlimited times or
based on the number of inputs in an iterator, and not
on a set number.
For
• Iterates over a starting and ending value by a given
value. It works exactly like For in any scripting/
programming language, executing through a set
number of items.
• Buffer Example
Buffer around Hospitals
Basic Model
Buffer around Hospitals
Add the For Iterator
Connect the output Value from
the For Iterator to the Buffer
tool. You most define the Buff
input for the Value .
Buffer around Hospitals
Define the iteration values
In the For iterator
Use “Value” as an
in-line variable substitution
to create a unique output
Hosp_buff%Value%
Buffer around Hospitals
Feedback
• In ModelBuilder, the output of a process can be used as an
input to a previous process. This is known as feedback, since
an output is fed back to a previous process as input.
Feedback
Define number of iterations
using the For iterator.
Feedback
• A feedback variable can be defined from a
variable properties or using the connect tool.
• %n% can be used to insert a systems variable
corresponding to the iteration number.
Feedback