Add log_histogram_raw to TensorBoardLogger (#1006)

Summary:
Pull Request resolved: #1006

The `SummaryWriter` supports `log_histogram_raw`. Enabling this feature in torchtnt will allow logging of pre-computed histograms.

Reviewed By: alanhdu

Differential Revision: D75455963

fbshipit-source-id: 000550ce9072093dc61e22735bd8734d30434d7c

Author: rkobler

tests/utils/loggers/test_tensorboard.py

@@ -81,6 +81,61 @@ def test_log_dict(self: TensorBoardLoggerTest) -> None:
                 )
                 self.assertEqual(tensor_tag.step, 1)
 
+    def test_log_histogram_raw(self: TensorBoardLoggerTest) -> None:
+        with tempfile.TemporaryDirectory() as log_dir:
+            logger = TensorBoardLogger(path=log_dir)
+
+            # generate a histogram with 4 bins in the range [0, 1]
+            data_range = [0.0, 1.0]
+            bucket_counts = [1, 3, 5, 4]
+            bucket_width = (data_range[1] - data_range[0]) / len(bucket_counts)
+            bucket_limits = [
+                ix * bucket_width + data_range[0]
+                for ix in range(len(bucket_counts) + 1)
+            ]
+            bucket_centers = [
+                (lower + upper) / 2
+                for lower, upper in zip(bucket_limits[:-1], bucket_limits[1:])
+            ]
+            # sum of the binned values
+            value_sum = float(
+                sum(
+                    value * count for value, count in zip(bucket_centers, bucket_counts)
+                )
+            )
+
+            logger.log_histogram_raw(
+                "histogram_raw",
+                min=0,
+                max=1,
+                num=sum(bucket_counts),
+                sum=value_sum,
+                sum_squares=value_sum**2,
+                bucket_limits=bucket_limits,
+                # add an extra leading 0 to match the format of the histogram_raw
+                bucket_counts=[0] + bucket_counts,
+            )
+            logger.close()
+
+            acc = EventAccumulator(log_dir)
+            acc.Reload()
+
+            # check that the histogram is logged correctly
+            self.assertIn("histogram_raw", acc.Tags()["histograms"])
+            # ensure that we logged exactly one histogram
+            self.assertEqual(len(acc.Histograms("histogram_raw")), 1)
+            histogram_event = acc.Histograms("histogram_raw")[0]
+            histogram_value = histogram_event.histogram_value
+            # check that the histogram is logged correctly
+            self.assertEqual(histogram_value.min, 0)
+            self.assertEqual(histogram_value.max, 1)
+            self.assertEqual(histogram_value.num, sum(bucket_counts))
+            self.assertEqual(histogram_value.sum, value_sum)
+            self.assertEqual(histogram_value.sum_squares, value_sum**2)
+            self.assertListEqual(histogram_value.bucket_limit, bucket_limits)
+            self.assertListEqual(histogram_value.bucket[1:], bucket_counts)
+            self.assertEqual(histogram_value.bucket[0], 0)
+
     def test_log_text(self: TensorBoardLoggerTest) -> None:
         with tempfile.TemporaryDirectory() as log_dir:
             logger = TensorBoardLogger(path=log_dir)

torchtnt/utils/loggers/tensorboard.py

@@ -210,7 +210,7 @@ def log_scalars(
             )
 
     def log_histogram(self: TensorBoardLogger, *args: Any, **kwargs: Any) -> None:
-        """Add histogram to TensorBoard.
+        """Compute and add histogram to TensorBoard.
 
         Args:
             *args (Any): Positional arguments passed to SummaryWriter.add_histogram
@@ -219,6 +219,16 @@ def log_histogram(self: TensorBoardLogger, *args: Any, **kwargs: Any) -> None:
         if self._writer:
             self._writer.add_histogram(*args, **kwargs)
 
+    def log_histogram_raw(self: TensorBoardLogger, *args: Any, **kwargs: Any) -> None:
+        """Add pre-computed histogram to TensorBoard.
+
+        Args:
+            *args (Any): Positional arguments passed to SummaryWriter.add_histogram_raw
+            **kwargs(Any): Keyword arguments passed to SummaryWriter.add_histogram_raw
+        """
+        if self._writer:
+            self._writer.add_histogram_raw(*args, **kwargs)
+
     def flush(self: TensorBoardLogger) -> None:
         """Writes pending logs to disk."""