pywatershed.PRMSStreamShadeConstant

class pywatershed.PRMSStreamShadeConstant(parameters, discretization=None)

Constant shade parameters by season.

Uses pre-specified constant shade values for summer and winter seasons. This is used when stream_temp_shade_flag = 1.

Requires 3 parameters: summer shade fraction, winter shade fraction, and segment latitude.

The compute() method returns a tuple of (shades, svis) where:

shades: Array of shade fractions (0-1) for all segments svis: Array of vegetation shade index (constant zero for this class)

__init__(parameters, discretization=None)

Initialize shade computer.

Parameters:

• parameters (Parameters) – Parameters object containing shade parameters

• discretization (Parameters) – Optional discretization parameters

Methods

__init__(parameters[, discretization])	Initialize shade computer.
compute(seg_idx, declination, summer_flag, ...)	Return constant shade value based on season.
compute_all(declination, summer_flag, ...)	Compute shade for all segments at once (vectorized).
get_parameters()	Get required constant shade parameters.

compute(seg_idx, declination, summer_flag, seg_flow_width)

Return constant shade value based on season.

Parameters:

• seg_idx (int) – Segment index (0-based)

• declination (float) – Solar declination (not used for constant shade)

• summer_flag (int) – 1 for summer, 0 for winter

• seg_flow_width (float) – Flow width (not used for constant shade)

Return type:

tuple[float, float]

Returns:

Tuple of (shade, svi) where – shades: Array of shade fractions (0-1) for all segments svis: Array of zeros (constant shade has no vegetation index)

compute_all(declination, summer_flag, seg_flow_widths)

Compute shade for all segments at once (vectorized).

Parameters:

• declination (float) – Solar declination (not used for constant shade)

• summer_flag (int) – 1 for summer, 0 for winter

• seg_flow_widths (ndarray) – Flow widths (not used for constant shade)

Return type:

tuple[ndarray, ndarray]

Returns:

Tuple of (shades, svis) where – shades: Array of shade fractions (0-1) for all segments svis: Array of zeros (constant shade has no vegetation index)

static get_parameters()

Get required constant shade parameters.

Return type:

tuple