Use incremental evaluation helper#

This example shows you how to use the incremental evaluation helper.

# Import necessary modules
from ansys.dpf import core as dpf
from ansys.dpf.core import examples

Retrieve an example to instantiate a DataSources object

path = examples.download_transient_result()
ds = dpf.DataSources(path)

# From the DataSources object we can retrieve the scoping
# In this example we want to compute the min/max for all the time sets
tf_provider = dpf.operators.metadata.time_freq_provider(data_sources=ds)
tf_support = tf_provider.get_output(output_type=dpf.types.time_freq_support)
scoping = dpf.time_freq_scoping_factory.scoping_on_all_time_freqs(tf_support)

# If you don't need to reuse TimeFreqSupport you could also use the DataSources
# scoping = dpf.time_freq_scoping_factory.scoping_on_all_time_freqs(ds)

Defining the workflow to exploit

# Instantiating a streams_provider is important when dealing with incremental evaluation
# due to multiple reuses of operators
streams_provider = dpf.operators.metadata.streams_provider(data_sources=ds)

# Defining the main workflow
result_op = dpf.operators.result.stress(
    data_sources=ds, time_scoping=scoping, streams_container=streams_provider
norm_fc = dpf.operators.math.norm_fc(result_op)
final_op = dpf.operators.min_max.min_max_fc_inc(norm_fc)

Obtain a new operator to retrieve outputs from

# Workflow is adapted from the first and the last operator in the current workflow
# Scoping is important to split the workload into chunks
new_end_op = dpf.split_workflow_in_chunks(result_op, final_op, scoping)

# Obtain results on the same pin numbers
min = new_end_op.get_output(0, dpf.types.field)
max = new_end_op.get_output(1, dpf.types.field)

# Plot results
import matplotlib.pyplot as plt

x =
plt.plot(x,, "b", label="Min")
plt.plot(x,, "r", label="Max")
14 incremental evaluation
Estimating chunk_size with max_bytes: 1073741824
Done. chunk_size set to 35 (scoping size: 35)

Total running time of the script: ( 0 minutes 3.606 seconds)

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