nvidia.dali.fn.constant¶
- nvidia.dali.fn.constant(*inputs, **kwargs)¶
Produces a batch of constant tensors.
The floating point input data should be placed in the
fdata
argument and integer data inidata
. The data, which can be a flat vector of values or a scalar, is then reshaped according to theshape
argument. If the data is scalar, it will be broadcast to fill the entire shape.The operator only performs meaningful work at first invocation; subsequent calls will return a reference to the same memory.
The operator can be automatically instantiated in Python with a call to
types.Constant(value, dtype, shape, layout)
. The value can be a scalar, a tuple, a list, or a numpy array. If not explicitly overridden, theshape
anddtype
, will be taken from the array.Warning
64-bit integer and double precision arrays are not supported and will be silently downgraded to 32-bit.
- Supported backends
‘cpu’
‘gpu’
- Keyword Arguments:
bytes_per_sample_hint (int or list of int, optional, default = [0]) –
Output size hint, in bytes per sample.
If specified, the operator’s outputs residing in GPU or page-locked host memory will be preallocated to accommodate a batch of samples of this size.
dtype (
nvidia.dali.types.DALIDataType
, optional) –Output data type.
If this value is not set, the output is float if the fdata argument is used and int if idata is used.
fdata (float or list of float, optional, default = []) –
Contents of the constant that is produced (for floating point types).
Note
fdata
andidata
are mutually exclusive, and one of them is required.idata (int or list of int, optional, default = []) –
Contents of the constant that is produced (for integer point types).
Note
fdata
andidata
are mutually exclusive, and one of them is required.layout (layout str, optional, default = ‘’) –
Layout info.
If set and not empty, the layout must match the dimensionality of the output.
preserve (bool, optional, default = False) – Prevents the operator from being removed from the graph even if its outputs are not used.
seed (int, optional, default = -1) –
Random seed.
If not provided, it will be populated based on the global seed of the pipeline.
shape (int or list of int, optional, default = []) – The desired shape of the output. If not set, the data is assumed to be 1D