Results for Static Analysis Surface Deformations

API & Interfaces
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1

Hello!

I've discovered an issue with the RFEM6 API (I think) when retrieving surface-related results. While node deformation results work correctly, all surface-related results (global deformations, local deformations, contact stresses) return empty DataFrames with incorrect column structures.

Environment:

  • RFEM6 Version: 6.11.0001
  • Python Version: 3.11.9
  • dlubal-api Version: 2.11.1

Issue Details:

  1. Working Correctly:
# This works as expected, returns proper node deformation results
rfem.results.STATIC_ANALYSIS_NODES_GLOBAL_DEFORMATIONS  # value 1
  1. Not Working (All Return Empty DataFrames):
# All of these return empty DataFrames with incorrect column structure
rfem.results.STATIC_ANALYSIS_SURFACES_GLOBAL_DEFORMATIONS_TABLE    # value 28
rfem.results.STATIC_ANALYSIS_SURFACES_LOCAL_DEFORMATIONS_TABLE     # value 29
rfem.results.STATIC_ANALYSIS_SURFACES_CONTACT_STRESSES_TABLE       # value 55
  1. API Response Issues:
    • When I ran for STATIC_ANALYSIS_SURFACES_GLOBAL_DEFORMATIONS_TABLE I got:
    • Empty DataFrame (0 rows)
    • Incorrect column structure (stress-related instead of deformation-related):
      ['loading', 'envelope', 'direction', 'mode_no', 'solid_no', 'surface_no', 
 'grid_point_no', 'location_x', 'location_y', 'location_z', 'tag', 
 'sigma_x', 'sigma_y', 'sigma_z', 'tau_yz', 'tau_xz', 'tau_xy']

Minimal Reproducible Example:

import logging
from dlubal.api import rfem
import dlubal.api

logger = logging.getLogger(__name__)
logger.info(f"dlubal.api version: {dlubal.api.__version__}")

# Initialize RFEM application
rfem_app = rfem.Application(api_key_value=YOUR_API_KEY)
rfem_app.open_model(path=MODEL_PATH)

# Test different surface result types
result_types = [
    rfem.results.STATIC_ANALYSIS_SURFACES_GLOBAL_DEFORMATIONS_TABLE,
    rfem.results.STATIC_ANALYSIS_SURFACES_LOCAL_DEFORMATIONS_TABLE,
    rfem.results.STATIC_ANALYSIS_SURFACES_CONTACT_STRESSES_TABLE
]

for result_type in result_types:
    logger.info(f"\nTesting: {result_type}")
    result_df = rfem_app.get_results(results_type=result_type).data
    logger.info(f"Shape: {result_df.shape}")
    logger.info(f"Columns: {list(result_df.columns)}")
    logger.info(f"Data:\n{result_df.head(1).to_string()}")

Expected Behavior:

  • Surface result types should return populated DataFrames like the node results do
  • Columns should match the result type (deformation columns for deformation results, etc.)
  • Loading cases should match those in the model

Current Status:

  1. Node results work perfectly (STATIC_ANALYSIS_NODES_GLOBAL_DEFORMATIONS)
  2. All surface-related results return empty DataFrames
  3. Column schemas don't match the requested result type (what I see in the RFEM6 UI)
  4. Results are definitely present in the model (visible in RFEM UI)

Questions:

  1. Is there something I am doing wrong and have misinterpreted the issue, or do you get the same thing?
  2. Is this a known issue with surface-related results in the API?
  3. Are there alternative result types we should be using for surface results?
  4. Is there a workaround available to access surface deformation data via the API?

Any assistance would be greatly appreciated. Let me know if you need any additional information or test cases.

3

Hi Samuel,

In general, the RFEM 6 API provides two distinct ways to retrieve results, depending on what you need:

:one: get_results – Full Raw Results

  • Returns all available data for the selected result type
  • Includes all columns and all data stored in the database, even those not visible in the GUI
  • Use result enums without the _TABLE postfix

:two: get_result_table – GUI-Like Table View

  • Returns the summary tables as shown in the RFEM desktop application
  • Contains only the most relevant values for quick review/export
  • Use result enums with the _TABLE postfix

:toolbox: Example:

# --- Retrieve results from the active model (already calculated) ---

# 1. get_results: Returns full dataset including all possible columns
df_internal_forces = rfem_app.get_results(
    results_type=rfem.results.ResultsType.STATIC_ANALYSIS_MEMBERS_INTERNAL_FORCES
).data
print(f"\nInternal Forces | All:")
print(df_internal_forces)

# 2. get_result_table: Returns GUI-like table (summary view)
df_internal_forces_table = rfem_app.get_result_table(
    table=rfem.results.ResultTable.STATIC_ANALYSIS_MEMBERS_INTERNAL_FORCES_TABLE,
    loading=rfem.ObjectId(
        no=1,
        object_type=rfem.OBJECT_TYPE_LOAD_COMBINATION
    )
).data
print(f"\nInternal Forces | Table:")
print(df_internal_forces_table)

# Both methods return a Table wrapper around pandas.DataFrame.
# Access the data directly via .data

:warning: Current limitation

At the moment, to retrieve surface deformation results, you need to use the get_result_table method together with the corresponding *_TABLE enums, such as:

STATIC_ANALYSIS_SURFACES_LOCAL_DEFORMATIONS_TABLE

Please note:

  • Currently, only grid point results are available via this method.
  • In upcoming releases, there will be a clear distinction between grid point results and mesh node results for surfaces.
  • The get_results method will also be extended soon to support the full set of surface results, similar to how it works for get_result_table.

Thank you for reporting this—your feedback helps us prioritize the next improvements!

4

Hi Tomas,

Thank you so much for that detailed and helpful explanation! I was able to adapt the code to the correct method you mentioned and was able to successfully extract the global deformation results. I am now very happy :)

Thanks again,
Samuel