Add print_alignment function

README.md

@@ -314,9 +314,53 @@ Sequences can be aligned, similar to `kaldialign.align`, using the tcpWER matchi
 ```python
 import meeteval
 meeteval.wer.wer.time_constrained.align([{'words': 'a b', 'start_time': 0, 'end_time': 1}], [{'words': 'a c', 'start_time': 0, 'end_time': 1}, {'words': 'd', 'start_time': 2, 'end_time': 3}], collar=5)
+alignment = meeteval.wer.wer.time_constrained.align([{'words': 'a b', 'start_time': 0, 'end_time': 1}], [{'words': 'a c', 'start_time': 0, 'end_time': 1}, {'words': 'd', 'start_time': 2, 'end_time': 3}], collar=5)
+print(alignment)
 # [('a', 'a'), ('b', 'c'), ('*', 'd')]
 ```
 
+`meeteval.wer.wer.time_constrained.print_alignment` pretty prints an an alignment with timestmaps:
+
+```python
+import meeteval
+alignment = meeteval.wer.wer.time_constrained.align(
+  [
+    {"words": "hi", "start_time": 0.93, "end_time": 2.03},
+    {"words": "good how are you", "start_time": 3.15, "end_time": 5.36},
+    {"words": "i'm leigh adams", "start_time": 7.24, "end_time": 8.36},
+    {"words": "pretty good now and you", "start_time": 9.44, "end_time": 12.27},
+    {"words": "yeah", "start_time": 15.49, "end_time": 16.95},
+  ],
+  [
+    {"words": "hi", "start_time": 0.93, "end_time": 2.03},
+    {"words": "are you", "start_time": 3.15, "end_time": 5.36},
+    {"words": "leigh adams", "start_time": 7.24, "end_time": 8.36},
+    {"words": "good now and", "start_time": 9.44, "end_time": 12.27},
+    {"words": "yep", "start_time": 15.49, "end_time": 16.95},
+  ], 
+  style='seglst',
+  collar=5,
+)
+
+meeteval.wer.wer.time_constrained.print_alignment(alignment)
+#  0.93  2.03     hi - hi     1.48  1.48
+#  3.15  3.83   good + *
+#  3.83  4.34    how + *
+#  4.34  4.85    are - are    3.70  3.70
+#  4.85  5.36    you - you    4.81  4.81
+#  7.24  7.50    i'm + *
+#  7.50  7.93  leigh - leigh  7.52  7.52
+#  7.93  8.36  adams - adams  8.08  8.08
+#  9.44 10.33 pretty + *
+# 10.33 10.93   good - good  10.01 10.01
+# 10.93 11.38    now - now   11.00 11.00
+# 11.38 11.82    and - and   11.85 11.85
+# 11.82 12.27    you + yep   16.22 16.22
+# 15.49 16.95   yeah + *
+```
+
+You can use `meeteval.wer.wer.time_constrained.format_alignment` to obtain a formatted string without printing.
+
 ## Visualization
 
 > [!TIP]
@@ -344,6 +388,7 @@ av = AlignmentVisualization(
     meeteval.io.load(folder + 'example_files/ref.stm').groupby('filename')['recordingA'],
     meeteval.io.load(folder + 'example_files/hyp.stm').groupby('filename')['recordingA']
 )
+
 # display(av)  # Jupyter
 # av.dump('viz.html')  # Create standalone HTML file
 ```

meeteval/wer/wer/time_constrained.py

@@ -34,6 +34,8 @@ class Segment(TypedDict):
     'apply_collar',
     'get_pseudo_word_level_timings',
     'align',
+    'format_alignment',
+    'print_alignment',
 ]
 
 
@@ -964,3 +966,56 @@ def align(
         raise ValueError(f'Unknown alignment style: {style}')
 
     return alignment
+
+def print_alignment(alignment, *, file=None):
+    """
+    Prints a seglst-style alignment (as produced by `align` with 
+    `style='seglst'`) in a human-readable format. Correct matches are marked 
+    with "-" and mismatches with "+".
+
+    >>> print_alignment(align(
+    ... [{'words': 'a', 'start_time': 0, 'end_time': 1}, {'words': 'b', 'start_time': 1, 'end_time': 2}, {'words': 'c', 'start_time': 2, 'end_time': 3}],
+    ... [{'words': 'a', 'start_time': 0, 'end_time': 1}, {'words': 'x', 'start_time': 1, 'end_time': 2}, {'words': 'c', 'start_time': 3, 'end_time': 4}],
+    ... style='seglst', collar=0)) # doctest: +NORMALIZE_WHITESPACE
+    0.00 1.00 a - a 0.50 0.50
+    1.00 2.00 b + x 1.50 1.50
+    2.00 3.00 c + *
+              * + c 3.50 3.50
+    """
+    lines = [
+        (
+            f'{left["start_time"]:.2f}' if left is not None else '',
+            f'{left["end_time"]:.2f}' if left is not None else '',
+            f'{left["words"]}' if left is not None else '*',
+            "-" if left is not None and right is not None and left["words"] == right["words"] else '+',
+            f'{right["words"]}' if right is not None else '*',
+            f'{right["start_time"]:.2f}' if right is not None else '',
+            f'{right["end_time"]:.2f}' if right is not None else ''
+        )
+        for left, right in alignment
+    ]
+
+    widths = [0] * len(lines[0])
+    justify = '>>>^<>>>>>'
+    for line in lines:
+        for i, item in enumerate(line):
+            widths[i] = max(widths[i], len(item))
+
+    for line in lines:
+        print(*[
+                f'{cell:{j}{w}}' 
+                for cell, j, w in zip(line, justify, widths)
+            ],
+            sep=' ',
+            file=file,
+        )
+
+
+def format_alignment(alignment):
+    """
+    Formats a seglst-style alignment as a human-readable string.
+    """
+    from io import StringIO
+    file = StringIO()
+    print_alignment(alignment, file=file)
+    return file.getvalue()

tests/test_docs.py

@@ -70,13 +70,12 @@ def split_code_block_comment_output(code):
         if l > s.end_lineno:
             continue
 
-        # If we parsed a print statement at the root level
-        if isinstance(s, ast.Expr) and isinstance(s.value, ast.Call) and isinstance(s.value.func, ast.Name) and s.value.func.id == 'print':
+        l = s.end_lineno
+
+        if l < len(lines) and lines[l].startswith('#'):
             # Collect any lines that follow directly and start with a #
             output = []
-            l = s.end_lineno
-            if not lines[l].startswith('#'):
-                continue
+
             while l < len(lines) and lines[l].startswith('#'):
                 output.append(lines[l][1:])
                 l += 1
@@ -139,7 +138,11 @@ def test_docs(filename, codeblock, global_state, monkeypatch):
                     # sufficient for most cases.
                     output_ = output.replace(' ', '').replace('\n', '')
                     expected_output_ = expected_output.replace(' ', '').replace('\n', '')
-                    assert output_ == expected_output_, f'Output mismatch: {output} != {expected_output}'
+                    if output_ != expected_output_:
+                        raise AssertionError(
+                            f'Output mismatch in {filename} at line {lineno + line_offset}:\n'
+                            f'Output: {output}\nExpected: {expected_output}'
+                        )
         elif lang == 'STM':
             # Test if the STM code block is valid.
             import meeteval