Error when trying to serve raster of float datatype containing NaN

127.0.0.1 - - [13/Jul/2020 00:31:22] "GET /singleband/4918/yield/0101201831012018/preview.png?tile_size=[128,128] HTTP/1.1" 500 -
 [-] Exception on /singleband/4918/yield/0101201831012018/preview.png [GET]
Traceback (most recent call last):
  File "/home/abhishek/anaconda3/envs/gis_env/lib/python3.8/site-packages/flask/app.py", line 2447, in wsgi_app
    response = self.full_dispatch_request()
  File "/home/abhishek/anaconda3/envs/gis_env/lib/python3.8/site-packages/flask/app.py", line 1952, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "/home/abhishek/anaconda3/envs/gis_env/lib/python3.8/site-packages/flask/app.py", line 1821, in handle_user_exception
    reraise(exc_type, exc_value, tb)
  File "/home/abhishek/anaconda3/envs/gis_env/lib/python3.8/site-packages/flask/_compat.py", line 39, in reraise
    raise value
  File "/home/abhishek/anaconda3/envs/gis_env/lib/python3.8/site-packages/flask/app.py", line 1950, in full_dispatch_request
    rv = self.dispatch_request()
  File "/home/abhishek/anaconda3/envs/gis_env/lib/python3.8/site-packages/flask/app.py", line 1936, in dispatch_request
    return self.view_functions[rule.endpoint](**req.view_args)
  File "/home/abhishek/Project/terracotta/terracotta/server/flask_api.py", line 49, in inner
    return fun(*args, **kwargs)
  File "/home/abhishek/Project/terracotta/terracotta/server/singleband.py", line 152, in get_singleband_preview
    return _get_singleband_image(keys)
  File "/home/abhishek/Project/terracotta/terracotta/server/singleband.py", line 166, in _get_singleband_image
    image = singleband(parsed_keys, tile_xyz=tile_xyz, **options)
  File "/home/abhishek/anaconda3/envs/gis_env/lib/python3.8/contextlib.py", line 75, in inner
    return func(*args, **kwds)
  File "/home/abhishek/Project/terracotta/terracotta/handlers/singleband.py", line 67, in singleband
    out = image.to_uint8(tile_data, *stretch_range_)
  File "/home/abhishek/Project/terracotta/terracotta/image.py", line 148, in to_uint8
    rescaled = contrast_stretch(data, (lower_bound, upper_bound), (1, 255), clip=True)
  File "/home/abhishek/anaconda3/envs/gis_env/lib/python3.8/contextlib.py", line 75, in inner
    return func(*args, **kwds)
  File "/home/abhishek/Project/terracotta/terracotta/image.py", line 134, in contrast_stretch
    out_data -= lower_bound_in
  File "/home/abhishek/anaconda3/envs/gis_env/lib/python3.8/site-packages/numpy/ma/core.py", line 4227, in __isub__
    self._data.__isub__(np.where(self._mask, self.dtype.type(0),
TypeError: ufunc 'subtract' output (typecode 'O') could not be coerced to provided output parameter (typecode 'd') according to the casting rule ''same_kind''

[dionhaefner]

Yes, there were two problems:

1. optimize-rasters did not work on rasters smaller than (256, 256).
2. Rasters containing a nodata value and NaN values could not be served. So, in general, float rasters did work, just not ones that also contain NaNs.

[dionhaefner]

Done. Feel free to reopen of the problem persists.