Module rio_tiler.expression¶

rio-tiler.expression: Parse and Apply expression.

Functions¶

def apply_expression(
    blocks: Sequence[str],
    bands: Sequence[str],
    data: numpy.ndarray
) -> numpy.ndarray

Apply rio-tiler expression.

Parameters:

Name	Type	Description	Default
blocks	sequence	expression for a specific layer.	None
bands	sequence	bands names.	None
data	numpy.array	array of bands.	None

Returns:

Type	Description
numpy.array	output data.

def get_expression_blocks(
    expression: str
) -> List[str]

Split expression in blocks.

Parameters:

Name	Type	Description	Default
expression	str	band math/combination expression.	None

Returns:

Type	Description
list	expression blocks (str).

def parse_expression(
    expression: str,
    cast: bool = True
) -> Tuple

Parse rio-tiler band math expression.

Parameters:

Name	Type	Description	Default
expression	str	band math/combination expression.	None
cast	bool	cast band names to integers (convert to index values). Defaults to True.	True

Returns:

Type	Description
tuple	band names/indexes.