use strings as ids in generators

src/spikeinterface/core/generate.py

@@ -134,7 +134,7 @@ def generate_sorting(
     seed = _ensure_seed(seed)
     rng = np.random.default_rng(seed)
     num_segments = len(durations)
-    unit_ids = np.arange(num_units)
+    unit_ids = [str(id) for id in np.arange(num_units)]
 
     spikes = []
     for segment_index in range(num_segments):
@@ -1111,7 +1111,7 @@ def __init__(
 
         """
 
-        unit_ids = np.arange(num_units)
+        unit_ids = [str(id) for id in np.arange(num_units)]
         super().__init__(sampling_frequency, unit_ids)
 
         self.num_units = num_units
@@ -1280,7 +1280,7 @@ def __init__(
         noise_block_size: int = 30000,
     ):
 
-        channel_ids = np.arange(num_channels)
+        channel_ids = [str(id) for id in np.arange(num_channels)]
         dtype = np.dtype(dtype).name  # Cast to string for serialization
         if dtype not in ("float32", "float64"):
             raise ValueError(f"'dtype' must be 'float32' or 'float64' but is {dtype}")