Merge pull request #429 from robbievanleeuwen/angle-section-fix

Fix angle_section bug when the toe thickness equals the section thickness

Author: robbievanleeuwen

.flake8

@@ -1,6 +1,6 @@
 [flake8]
 select = B,B9,C,D,DAR,E,F,N,PT,RST,S,W
-ignore = B028,B905,E203,E501,E741,RST201,RST203,RST301,RST303,W503
+ignore = B028,B905,B908,E203,E501,E741,RST201,RST203,RST301,RST303,W503
 max-line-length = 80
 docstring-convention = google
 per-file-ignores = tests/*:S101,__init__.py:F401,post.py:C901

src/sectionproperties/pre/library/steel_sections.py

@@ -985,7 +985,7 @@ def angle_section(
         Angle section geometry
 
     Raises:
-        ValueError: If the toe radius is larger than the toe thickness
+        ValueError: If the toe radius is larger than the thickness
 
     Example:
         The following example creates an angle section with a depth of 150 mm, a width
@@ -1002,14 +1002,16 @@ def angle_section(
     """
     if r_t > t:
         raise ValueError(
-            "The radius of the toe (r_t) cannot be larger than the toe thickness (t)."
+            "The radius of the toe (r_t) cannot be larger than the thickness (t)."
         )
 
     points: list[tuple[float, float]] = []
 
-    # add first two points
+    # add first two points, but don't add second if the toe radius equals the thickness
     points.append((0, 0))
-    points.append((b, 0))
+
+    if not np.isclose(t, r_t):
+        points.append((b, 0))
 
     # construct the bottom toe radius
     pt = b - r_t, t - r_t
@@ -1023,8 +1025,9 @@ def angle_section(
     pt = t - r_t, d - r_t
     points += sp_utils.draw_radius(pt=pt, r=r_t, theta=0, n=n_r)
 
-    # add the next point
-    points.append((0, d))
+    # add the last point, only if the toe radius does not equal the thickness
+    if not np.isclose(t, r_t):
+        points.append((0, d))
 
     polygon = Polygon(points)
 

tests/section_library/test_steel_sections.py

@@ -0,0 +1,25 @@
+"""Tests for the steel sections library."""
+
+from __future__ import annotations
+
+import warnings
+
+import pytest
+
+import sectionproperties.pre.library.steel_sections as ss
+from sectionproperties.analysis import Section
+
+
+def test_angle_section_toe_thickness():
+    """Tests the angle section when the toe thickness equals the thickness."""
+    geom = ss.angle_section(d=20, b=20, t=3, r_r=3.5, r_t=3, n_r=16)
+    geom.create_mesh(mesh_sizes=1.0)
+    sec = Section(geom)
+
+    # check for no additional warnings
+    with pytest.warns() as record:
+        warnings.warn("user", UserWarning)
+        sec.calculate_geometric_properties()
+        sec.calculate_warping_properties()
+
+    assert len(record) == 1