openswmm_xsect.h File Reference

OpenSWMM Engine — standalone cross-section geometry C API. More...

#include "openswmm_engine.h"
#include "openswmm_links.h"

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Typedefs
typedef void *	SWMM_XSect
	Opaque handle to a standalone cross-section. Free with swmm_xsect_free().
typedef enum SWMM_UnitSystem	SWMM_UnitSystem
	Unit system for a standalone cross-section.

Enumerations
enum	SWMM_UnitSystem {   SWMM_UNITS_US = 0 ,   SWMM_UNITS_SI = 1 }
	Unit system for a standalone cross-section. More...

Functions
SWMM_ENGINE_API int	swmm_xsect_create (int shape, double geom1, double geom2, double geom3, double geom4, int unit_system, SWMM_XSect *out)
	Create a cross-section from a shape code and its geometry parameters.
SWMM_ENGINE_API int	swmm_xsect_create_irregular (const double *stations, const double *elevations, int n_pts, double x_left_bank, double x_right_bank, double n_left, double n_channel, double n_right, double length_factor, int unit_system, SWMM_XSect *out)
	Create an irregular (natural channel) cross-section from a transect.
SWMM_ENGINE_API int	swmm_xsect_create_custom (double y_full, const double *curve_depths, const double *curve_widths, int n_pts, int unit_system, SWMM_XSect *out)
	Create a custom cross-section from a normalized shape curve.
SWMM_ENGINE_API int	swmm_xsect_create_street (double width, double curb_height, double slope, double roughness, double gutter_depression, double gutter_width, int sides, double back_width, double back_slope, double back_roughness, int unit_system, SWMM_XSect *out)
	Create a street cross-section.
SWMM_ENGINE_API int	swmm_link_create_xsect (SWMM_Engine engine, int link_idx, SWMM_XSect *out)
	Create a cross-section from a link of an open model.
SWMM_ENGINE_API int	swmm_xsect_free (SWMM_XSect xsect)
	Release a cross-section handle.
SWMM_ENGINE_API int	swmm_xsect_get_shape (SWMM_XSect xsect, int *shape)
	Get the shape code of a cross-section.
SWMM_ENGINE_API int	swmm_xsect_get_units (SWMM_XSect xsect, int *unit_system, int *flow_units)
	Get the unit system and flow units a handle reports its results in.
SWMM_ENGINE_API const char *	swmm_xsect_shape_name (int shape)
	Get the name of a cross-section shape code.
SWMM_ENGINE_API int	swmm_xsect_area_of_depth (SWMM_XSect xsect, double depth, double *area)
	Flow area at a given depth.
SWMM_ENGINE_API int	swmm_xsect_width_of_depth (SWMM_XSect xsect, double depth, double *width)
	Top width of the water surface at a given depth.
SWMM_ENGINE_API int	swmm_xsect_hydrad_of_depth (SWMM_XSect xsect, double depth, double *hydrad)
	Hydraulic radius (area / wetted perimeter) at a given depth.
SWMM_ENGINE_API int	swmm_xsect_depth_of_area (SWMM_XSect xsect, double area, double *depth)
	Depth of flow for a given area — the inverse of swmm_xsect_area_of_depth().
SWMM_ENGINE_API int	swmm_xsect_hydrad_of_area (SWMM_XSect xsect, double area, double *hydrad)
	Hydraulic radius for a given area.
SWMM_ENGINE_API int	swmm_xsect_sectfactor_of_area (SWMM_XSect xsect, double area, double *sf)
	Section factor (A·R^(2/3)) for a given area.
SWMM_ENGINE_API int	swmm_xsect_area_of_sectfactor (SWMM_XSect xsect, double sf, double *area)
	Flow area for a given section factor — the inverse of swmm_xsect_sectfactor_of_area(), used to solve for normal depth.
SWMM_ENGINE_API int	swmm_xsect_dsda (SWMM_XSect xsect, double area, double *dsda)
	Derivative of the section factor with respect to area, dS/dA.
SWMM_ENGINE_API int	swmm_xsect_critical_depth (SWMM_XSect xsect, double flow, double *ycrit)
	Critical depth for a given flow.
SWMM_ENGINE_API int	swmm_xsect_full_properties (SWMM_XSect xsect, double *y_full, double *a_full, double *r_full, double *w_max, double *s_full, double *a_max)
	Full-depth (bank-full) properties of the cross-section.
SWMM_ENGINE_API int	swmm_xsect_is_open (SWMM_XSect xsect, int *is_open)
	Whether the cross-section is open to the atmosphere at its top.
SWMM_ENGINE_API int	swmm_xsect_area_of_depth_array (SWMM_XSect xsect, const double *depth, int n, double *area)
	Array form of swmm_xsect_area_of_depth().
SWMM_ENGINE_API int	swmm_xsect_width_of_depth_array (SWMM_XSect xsect, const double *depth, int n, double *width)
	Array form of swmm_xsect_width_of_depth().
SWMM_ENGINE_API int	swmm_xsect_hydrad_of_depth_array (SWMM_XSect xsect, const double *depth, int n, double *hydrad)
	Array form of swmm_xsect_hydrad_of_depth().
SWMM_ENGINE_API int	swmm_xsect_depth_of_area_array (SWMM_XSect xsect, const double *area, int n, double *depth)
	Array form of swmm_xsect_depth_of_area().
SWMM_ENGINE_API int	swmm_xsect_hydrad_of_area_array (SWMM_XSect xsect, const double *area, int n, double *hydrad)
	Array form of swmm_xsect_hydrad_of_area().
SWMM_ENGINE_API int	swmm_xsect_sectfactor_of_area_array (SWMM_XSect xsect, const double *area, int n, double *sf)
	Array form of swmm_xsect_sectfactor_of_area().
SWMM_ENGINE_API int	swmm_xsect_area_of_sectfactor_array (SWMM_XSect xsect, const double *sf, int n, double *area)
	Array form of swmm_xsect_area_of_sectfactor().
SWMM_ENGINE_API int	swmm_xsect_dsda_array (SWMM_XSect xsect, const double *area, int n, double *dsda)
	Array form of swmm_xsect_dsda().
SWMM_ENGINE_API int	swmm_xsect_critical_depth_array (SWMM_XSect xsect, const double *flow, int n, double *ycrit)
	Array form of swmm_xsect_critical_depth().

Detailed Description

OpenSWMM Engine — standalone cross-section geometry C API.

Exposes the engine's canonical cross-section geometry kernels as a reference implementation usable without a model. Construct a cross-section from shape + geometry parameters (or from transect, shape-curve or street data), then query area / top width / hydraulic radius / section factor / critical depth and their inverses. The same functions the routing solvers use answer these queries, so results agree with a simulation bit-for-bit.

A handle can also be taken from a link of an open model (swmm_link_create_xsect), using the geometry the engine actually built — including transect tables. Such a handle owns a deep copy and stays valid after the engine is closed.

SWMM_XSect xs;
swmm_xsect_create(SWMM_XSECT_CIRCULAR, 1.0, 0, 0, 0,
                  SWMM_UNITS_SI, &xs);
double a;
swmm_xsect_area_of_depth(xs, 0.5, &a);   // half-full 1 m pipe
swmm_xsect_free(xs);

Units

Every geometry value crossing this API is in the handle's display units, matching the rest of the C API: lengths in ft (US) or m (SI), areas in ft² / m², section factors in ft^(8/3) / m^(8/3). Flows (for swmm_xsect_critical_depth) are in the handle's flow units — CFS for a standalone US handle, CMS for a standalone SI handle, and the model's own flow units for a handle taken from a link. Query them with swmm_xsect_get_units().

See also

openswmm_links.h — SWMM_XSectShape shape codes and per-link geometry.

Author

Caleb Buahin caleb.nosp@m..bua.nosp@m.hin@g.nosp@m.mail.nosp@m..com

Copyright

Copyright (c) 2026 Caleb Buahin. All rights reserved.

License\n MIT License

Typedef Documentation

SWMM_UnitSystem

typedef enum SWMM_UnitSystem SWMM_UnitSystem

Unit system for a standalone cross-section.

Matches the engine's internal 0=US / 1=SI coding (see swmm_get_unit_system()). Selects both the length units (ft vs m) and the default flow unit used by swmm_xsect_critical_depth() (CFS vs CMS).

SWMM_XSect

typedef void* SWMM_XSect

Opaque handle to a standalone cross-section. Free with swmm_xsect_free().

Enumeration Type Documentation

SWMM_UnitSystem

enum SWMM_UnitSystem

Unit system for a standalone cross-section.

Matches the engine's internal 0=US / 1=SI coding (see swmm_get_unit_system()). Selects both the length units (ft vs m) and the default flow unit used by swmm_xsect_critical_depth() (CFS vs CMS).

Enumerator
SWMM_UNITS_US	Feet, ft², ft^(8/3), CFS.
SWMM_UNITS_SI	Metres, m², m^(8/3), CMS.

Function Documentation

swmm_link_create_xsect()

SWMM_ENGINE_API int swmm_link_create_xsect	(	SWMM_Engine	engine,
		int	link_idx,
		SWMM_XSect *	out )

Create a cross-section from a link of an open model.

Deep-copies the geometry the engine actually built for the link, including any transect / shape-curve / street tables, so the handle remains valid after the engine is closed or destroyed. The handle inherits the model's unit system and flow units.

Note

Requires resolved geometry. A model still under programmatic construction has only the raw geoms stored, not the derived full-flow properties, so this returns SWMM_ERR_LIFECYCLE until swmm_finalize_model() (or swmm_engine_open()) has run.

Parameters

	engine	Engine handle with geometry resolved (OPENED or later).
	link_idx	Zero-based link index.
[out]	out	Receives the new handle on success.

Returns

SWMM_OK; SWMM_ERR_BADHANDLE for a NULL engine; SWMM_ERR_BADINDEX if link_idx is out of range; SWMM_ERR_LIFECYCLE if the model is still in the BUILDING state; SWMM_ERR_BADPARAM if out is NULL or the link has no cross-section (e.g. a pump).

Since

6.0

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swmm_xsect_area_of_depth()

SWMM_ENGINE_API int swmm_xsect_area_of_depth	(	SWMM_XSect	xsect,
		double	depth,
		double *	area )

Flow area at a given depth.

Parameters

	xsect	Cross-section handle.
	depth	Depth of flow, display units. Depths above the full depth of a closed shape are clamped, as in the routing solvers.
[out]	area	Receives the area, display units squared.

Returns

SWMM_OK; SWMM_ERR_BADHANDLE; SWMM_ERR_BADPARAM if area is NULL or depth is negative or not finite.

Since

6.0

swmm_xsect_area_of_depth_array()

SWMM_ENGINE_API int swmm_xsect_area_of_depth_array	(	SWMM_XSect	xsect,
		const double *	depth,
		int	n,
		double *	area )

Array form of swmm_xsect_area_of_depth().

Since

6.0

swmm_xsect_area_of_sectfactor()

SWMM_ENGINE_API int swmm_xsect_area_of_sectfactor	(	SWMM_XSect	xsect,
		double	sf,
		double *	area )

Flow area for a given section factor — the inverse of swmm_xsect_sectfactor_of_area(), used to solve for normal depth.

Parameters

	xsect	Cross-section handle.
	sf	Section factor, display units^(8/3).
[out]	area	Receives the area, display units squared.

Returns

SWMM_OK; SWMM_ERR_BADHANDLE; SWMM_ERR_BADPARAM if area is NULL or sf is negative or not finite.

Since

6.0

swmm_xsect_area_of_sectfactor_array()

SWMM_ENGINE_API int swmm_xsect_area_of_sectfactor_array	(	SWMM_XSect	xsect,
		const double *	sf,
		int	n,
		double *	area )

Array form of swmm_xsect_area_of_sectfactor().

Since

6.0

swmm_xsect_create()

SWMM_ENGINE_API int swmm_xsect_create	(	int	shape,
		double	geom1,
		double	geom2,
		double	geom3,
		double	geom4,
		int	unit_system,
		SWMM_XSect *	out )

Create a cross-section from a shape code and its geometry parameters.

Handles every self-contained shape — i.e. all of SWMM_XSectShape except SWMM_XSECT_IRREGULAR, SWMM_XSECT_CUSTOM and SWMM_XSECT_STREET, whose geometry comes from tabulated data and which have their own constructors below.

geom1–geom4 carry the same meaning as the [XSECTIONS] Geom1–Geom4 columns; see the per-shape notes on SWMM_XSectShape. Unused parameters may be passed as 0.

Note

SWMM_XSECT_FORCE_MAIN is geometrically identical to SWMM_XSECT_CIRCULAR; it differs only in its friction law (its section factor uses the Hazen-Williams exponent), so its geometric queries match a circular pipe of the same diameter.

SWMM_XSECT_DUMMY has no geometry: it constructs successfully and every query returns 0.

Parameters

	shape	A SWMM_XSectShape code.
	geom1	Full depth / diameter, in display units (see units).
	geom2	Second geometry parameter, or 0.
	geom3	Third geometry parameter, or 0.
	geom4	Fourth geometry parameter, or 0.
	unit_system	A SWMM_UnitSystem value.
[out]	out	Receives the new handle on success.

Returns

SWMM_OK, or SWMM_ERR_BADPARAM if out is NULL, shape is not a valid self-contained shape, unit_system is out of range, or the geometry is degenerate (e.g. non-positive depth).

Since

6.0

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swmm_xsect_create_custom()

SWMM_ENGINE_API int swmm_xsect_create_custom	(	double	y_full,
		const double *	curve_depths,
		const double *	curve_widths,
		int	n_pts,
		int	unit_system,
		SWMM_XSect *	out )

Create a custom cross-section from a normalized shape curve.

Mirrors a SHAPE-type [CURVES] entry scaled to y_full: curve_depths are y/yFull in [0,1] and curve_widths are the corresponding width/wMax.

Parameters

	y_full	Full depth of the section, display units (> 0).
	curve_depths	Normalized depths (y/yFull), ascending.
	curve_widths	Normalized widths (w/wMax) at each depth.
	n_pts	Number of curve points (>= 2).
	unit_system	A SWMM_UnitSystem value.
[out]	out	Receives the new handle on success.

Returns

SWMM_OK, or SWMM_ERR_BADPARAM on a NULL pointer, n_pts < 2, y_full <= 0, or an out-of-range unit_system.

Since

6.0

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swmm_xsect_create_irregular()

SWMM_ENGINE_API int swmm_xsect_create_irregular	(	const double *	stations,
		const double *	elevations,
		int	n_pts,
		double	x_left_bank,
		double	x_right_bank,
		double	n_left,
		double	n_channel,
		double	n_right,
		double	length_factor,
		int	unit_system,
		SWMM_XSect *	out )

Create an irregular (natural channel) cross-section from a transect.

Mirrors an [TRANSECTS] entry: stations/elevations are the GR station-elevation pairs, and the Manning's n triple is the NC line. The roughness values are load-bearing, not decorative — the hydraulic-radius table is conveyance-weighted across the left overbank / channel / right overbank subsections, so passing the wrong n changes the geometry this handle reports.

Parameters

	stations	Station (horizontal) coordinates, display units, ascending.
	elevations	Elevation at each station, display units.
	n_pts	Number of station/elevation pairs (>= 2).
	x_left_bank	Station where the left overbank ends. Pass the same value as x_right_bank for a channel with no overbanks.
	x_right_bank	Station where the right overbank begins.
	n_left	Manning's n, left overbank. 0 → use n_channel.
	n_channel	Manning's n, main channel. Must be > 0.
	n_right	Manning's n, right overbank. 0 → use n_channel.
	length_factor	Main-channel / flood-plain length ratio. 0 → 1.0.
	unit_system	A SWMM_UnitSystem value.
[out]	out	Receives the new handle on success.

Returns

SWMM_OK, or SWMM_ERR_BADPARAM on a NULL pointer, n_pts < 2, n_channel <= 0, an out-of-range unit_system, or a transect whose stations yield no wetted area.

Since

6.0

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swmm_xsect_create_street()

SWMM_ENGINE_API int swmm_xsect_create_street	(	double	width,
		double	curb_height,
		double	slope,
		double	roughness,
		double	gutter_depression,
		double	gutter_width,
		int	sides,
		double	back_width,
		double	back_slope,
		double	back_roughness,
		int	unit_system,
		SWMM_XSect *	out )

Create a street cross-section.

Mirrors a [STREETS] entry; parameters match swmm_street_set_params(). Slopes are percentages, as in the input file.

Parameters

	width	Distance from curb to crown, display units.
	curb_height	Curb height, display units.
	slope	Transverse road slope, percent.
	roughness	Manning's n of the road surface (> 0).
	gutter_depression	Depressed-gutter depth, display units.
	gutter_width	Depressed-gutter width, display units.
	sides	1 = half street, 2 = full street.
	back_width	Backing width, display units (0 if none).
	back_slope	Backing slope, percent.
	back_roughness	Backing Manning's n.
	unit_system	A SWMM_UnitSystem value.
[out]	out	Receives the new handle on success.

Returns

SWMM_OK, or SWMM_ERR_BADPARAM on a NULL out, a non-positive width/curb height/roughness, sides outside {1,2}, or an out-of-range unit_system.

Since

6.0

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swmm_xsect_critical_depth()

SWMM_ENGINE_API int swmm_xsect_critical_depth	(	SWMM_XSect	xsect,
		double	flow,
		double *	ycrit )

Critical depth for a given flow.

Parameters

	xsect	Cross-section handle.
	flow	Flow, in the handle's flow units (see swmm_xsect_get_units()).
[out]	ycrit	Receives the critical depth, display units.

Returns

SWMM_OK; SWMM_ERR_BADHANDLE; SWMM_ERR_BADPARAM if ycrit is NULL or flow is negative or not finite.

Since

6.0

swmm_xsect_critical_depth_array()

SWMM_ENGINE_API int swmm_xsect_critical_depth_array	(	SWMM_XSect	xsect,
		const double *	flow,
		int	n,
		double *	ycrit )

Array form of swmm_xsect_critical_depth().

Since

6.0

swmm_xsect_depth_of_area()

SWMM_ENGINE_API int swmm_xsect_depth_of_area	(	SWMM_XSect	xsect,
		double	area,
		double *	depth )

Depth of flow for a given area — the inverse of swmm_xsect_area_of_depth().

Parameters

	xsect	Cross-section handle.
	area	Flow area, display units squared.
[out]	depth	Receives the depth, display units.

Returns

SWMM_OK; SWMM_ERR_BADHANDLE; SWMM_ERR_BADPARAM if depth is NULL or area is negative or not finite.

Since

6.0

swmm_xsect_depth_of_area_array()

SWMM_ENGINE_API int swmm_xsect_depth_of_area_array	(	SWMM_XSect	xsect,
		const double *	area,
		int	n,
		double *	depth )

Array form of swmm_xsect_depth_of_area().

Since

6.0

swmm_xsect_dsda()

SWMM_ENGINE_API int swmm_xsect_dsda	(	SWMM_XSect	xsect,
		double	area,
		double *	dsda )

Derivative of the section factor with respect to area, dS/dA.

Parameters

	xsect	Cross-section handle.
	area	Flow area, display units squared.
[out]	dsda	Receives dS/dA, display units^(2/3).

Returns

SWMM_OK; SWMM_ERR_BADHANDLE; SWMM_ERR_BADPARAM if dsda is NULL or area is negative or not finite.

Since

6.0

swmm_xsect_dsda_array()

SWMM_ENGINE_API int swmm_xsect_dsda_array	(	SWMM_XSect	xsect,
		const double *	area,
		int	n,
		double *	dsda )

Array form of swmm_xsect_dsda().

Since

6.0

swmm_xsect_free()

SWMM_ENGINE_API int swmm_xsect_free

(

SWMM_XSect

xsect

)

Release a cross-section handle.

Parameters

xsect

Handle from any swmm_xsect_create* / swmm_link_create_xsect. NULL is accepted and ignored.

Returns

SWMM_OK.

Since

6.0

swmm_xsect_full_properties()

SWMM_ENGINE_API int swmm_xsect_full_properties	(	SWMM_XSect	xsect,
		double *	y_full,
		double *	a_full,
		double *	r_full,
		double *	w_max,
		double *	s_full,
		double *	a_max )

Full-depth (bank-full) properties of the cross-section.

Every out-parameter is optional — pass NULL for any value not wanted.

Parameters

	xsect	Cross-section handle.
[out]	y_full	Full depth, display units.
[out]	a_full	Area when full, display units squared.
[out]	r_full	Hydraulic radius when full, display units.
[out]	w_max	Width at the widest point, display units.
[out]	s_full	Section factor when full, display units^(8/3).
[out]	a_max	Area at which flow is a maximum, display units squared.

Returns

SWMM_OK or SWMM_ERR_BADHANDLE.

Since

6.0

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swmm_xsect_get_shape()

SWMM_ENGINE_API int swmm_xsect_get_shape	(	SWMM_XSect	xsect,
		int *	shape )

Get the shape code of a cross-section.

Parameters

	xsect	Cross-section handle.
[out]	shape	Receives a SWMM_XSectShape code.

Returns

SWMM_OK, SWMM_ERR_BADHANDLE, or SWMM_ERR_BADPARAM if shape is NULL.

Since

6.0

swmm_xsect_get_units()

SWMM_ENGINE_API int swmm_xsect_get_units	(	SWMM_XSect	xsect,
		int *	unit_system,
		int *	flow_units )

Get the unit system and flow units a handle reports its results in.

flow_units matters only for swmm_xsect_critical_depth(); every other query is governed by unit_system alone.

Parameters

	xsect	Cross-section handle.
[out]	unit_system	Receives a SWMM_UnitSystem value (may be NULL).
[out]	flow_units	Receives the flow-unit code (may be NULL): 0=CFS, 1=GPM, 2=MGD, 3=CMS, 4=LPS, 5=MLD. A standalone handle reports CFS (US) or CMS (SI); a handle from a link reports its model's units.

Returns

SWMM_OK or SWMM_ERR_BADHANDLE.

Since

6.0

swmm_xsect_hydrad_of_area()

SWMM_ENGINE_API int swmm_xsect_hydrad_of_area	(	SWMM_XSect	xsect,
		double	area,
		double *	hydrad )

Hydraulic radius for a given area.

Parameters

	xsect	Cross-section handle.
	area	Flow area, display units squared.
[out]	hydrad	Receives the hydraulic radius, display units.

Returns

SWMM_OK; SWMM_ERR_BADHANDLE; SWMM_ERR_BADPARAM if hydrad is NULL or area is negative or not finite.

Since

6.0

swmm_xsect_hydrad_of_area_array()

SWMM_ENGINE_API int swmm_xsect_hydrad_of_area_array	(	SWMM_XSect	xsect,
		const double *	area,
		int	n,
		double *	hydrad )

Array form of swmm_xsect_hydrad_of_area().

Since

6.0

swmm_xsect_hydrad_of_depth()

SWMM_ENGINE_API int swmm_xsect_hydrad_of_depth	(	SWMM_XSect	xsect,
		double	depth,
		double *	hydrad )

Hydraulic radius (area / wetted perimeter) at a given depth.

Parameters

	xsect	Cross-section handle.
	depth	Depth of flow, display units.
[out]	hydrad	Receives the hydraulic radius, display units.

Returns

SWMM_OK; SWMM_ERR_BADHANDLE; SWMM_ERR_BADPARAM if hydrad is NULL or depth is negative or not finite.

Since

6.0

swmm_xsect_hydrad_of_depth_array()

SWMM_ENGINE_API int swmm_xsect_hydrad_of_depth_array	(	SWMM_XSect	xsect,
		const double *	depth,
		int	n,
		double *	hydrad )

Array form of swmm_xsect_hydrad_of_depth().

Since

6.0

swmm_xsect_is_open()

SWMM_ENGINE_API int swmm_xsect_is_open	(	SWMM_XSect	xsect,
		int *	is_open )

Whether the cross-section is open to the atmosphere at its top.

Parameters

	xsect	Cross-section handle.
[out]	is_open	Receives 1 for an open channel, 0 for a closed conduit.

Returns

SWMM_OK; SWMM_ERR_BADHANDLE; SWMM_ERR_BADPARAM if is_open is NULL.

Since

6.0

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swmm_xsect_sectfactor_of_area()

SWMM_ENGINE_API int swmm_xsect_sectfactor_of_area	(	SWMM_XSect	xsect,
		double	area,
		double *	sf )

Section factor (A·R^(2/3)) for a given area.

Parameters

	xsect	Cross-section handle.
	area	Flow area, display units squared.
[out]	sf	Receives the section factor, display units^(8/3).

Returns

SWMM_OK; SWMM_ERR_BADHANDLE; SWMM_ERR_BADPARAM if sf is NULL or area is negative or not finite.

Since

6.0

swmm_xsect_sectfactor_of_area_array()

SWMM_ENGINE_API int swmm_xsect_sectfactor_of_area_array	(	SWMM_XSect	xsect,
		const double *	area,
		int	n,
		double *	sf )

Array form of swmm_xsect_sectfactor_of_area().

Since

6.0

swmm_xsect_shape_name()

SWMM_ENGINE_API const char * swmm_xsect_shape_name

(

int

shape

)

Get the name of a cross-section shape code.

Useful for reporting, and for checking a code at runtime after the 6.0 SWMM_XSectShape renumbering (see openswmm_links.h).

Parameters

shape

A SWMM_XSectShape code.

Returns

A static, never-freed string such as "CIRCULAR", or NULL if shape is not a valid code.

Since

6.0

swmm_xsect_width_of_depth()

SWMM_ENGINE_API int swmm_xsect_width_of_depth	(	SWMM_XSect	xsect,
		double	depth,
		double *	width )

Top width of the water surface at a given depth.

Parameters

	xsect	Cross-section handle.
	depth	Depth of flow, display units.
[out]	width	Receives the top width, display units.

Returns

SWMM_OK; SWMM_ERR_BADHANDLE; SWMM_ERR_BADPARAM if width is NULL or depth is negative or not finite.

Since

6.0

swmm_xsect_width_of_depth_array()

SWMM_ENGINE_API int swmm_xsect_width_of_depth_array	(	SWMM_XSect	xsect,
		const double *	depth,
		int	n,
		double *	width )

Array form of swmm_xsect_width_of_depth().

Since

6.0