civpy.survey.Alignment

class civpy.survey.Alignment(name, pis=[], stakes=[], grid=10, view_offset=15, view_margin=15)

A class representing a survey alignment.

Parameters:

name : str

Name of alignment.

pis : list

A list of PI.

stakes : list

A list of SurveyStake.

grid : float

The grid size used for spatial hash generation.

view_offset : float

The offset beyond which points will be ignored when generating station coordinates from global coordinates.

view_margin : float

The station margin at the beginning and end of the alignment. Beyond this threshold, generated station coordinates from global coordinates will be ignored.

Examples

# alignment_ex1.py
from civpy.survey import PI, Alignment, SurveyStake

# PI coordinates
p = [
    #   x,    y  z,  r
    (-100, -200, 0,  0),
    (-200, -200, 0, 40),
    (-200,  200, 0, 40),
    ( 200,  200, 0, 40),
    ( 200, -200, 0, 40),
    ( 100, -200, 0, 40),
    ( 100,  100, 0, 40),
    (-100,  100, 0, 40),
    (-100, -100, 0, 40),
    (   0, -100, 0, 40),
    (   0,    0, 0,  0)
]

# Stake survey stations
q = [
    # sta, off, z, ht,      rot,
    (   0,  30, 0, 0, -0.78539),
    ( 100,  30, 0, 0,        0),
    ( 300, -30, 0, 0,        0),
    ( 475, -30, 0, 0,        0),
    (1000,   0, 0, 0,        0),
    (1975, -30, 0, 0,        0)
]

p = [PI(*x) for x in p]
q = [SurveyStake.init_station(*x) for x in q]

align = Alignment('Alignment', pis=p, stakes=q)
align.plot_plan()

(Source code, png, hires.png, pdf)

Methods

azimuths(self)	Returns an array of alignment azimuths in the shape (N,).
chord_distances(self)	Returns an array of chord distances corresponding to each PI in teh shape (N,).
coordinates(self, sta_coords)	Returns the (x, y) or (x, y, z) global coordinates corresponding to the input station coordinates.
curve_lengths(self)	Returns an array of horizontal curve lengths corresponding to each PI in teh shape (N,).
deflection_angles(self)	Returns an array of PI deflection angles in the shape (N,).
external_ordinates(self)	Returns an array of external ordinates corresponding to each PI in the shape (N,).
middle_ordinates(self)	Returns an array of middle ordinate distances corresponding to each PI in the shape (N,).
mpc_coordinates(self)	Returns an array of (x, y) coordinates for the Midpoint of Curves (MPC) in the shape (N, 2).
mpc_stations(self)	Returns an array of stations for the Midpoint of Curves (MPC) in the shape (N,).
pc_coordinates(self)	Returns an array of (x, y) coordinates for the Point of Curves (PC) in the shape (N, 2).
pc_stations(self)	Returns an array of stations for the Point of Curves (PC) in the shape (N,).
pi_coordinates(self)	Returns an array of PI coordinates of shape (N, 3).
pi_radii(self)	Returns an array of PI horizontal curve radii of shape (N,).
plot_plan(self[, ax, step, symbols])	Plots a the plan view for the alignment.
poc_transforms(self)	Returns the POC transforms in the shape (N, 2, 2).
pot_transforms(self)	Returns the POT transforms in the shape (N, 2, 2).
pt_coordinates(self)	Returns an array of (x, y) coordinates for the Point of Tangents (PT) in the shape (N, 2).
pt_stations(self)	Returns an array of (x, y) coordinates for the Point of Tangents (PT) in the shape (N, 2).
rp_coordinates(self)	Returns an array of (x, y) coordinates for the Radius Points (RP) in the shape (N, 2).
segment_indices(self, stations)	Determines the segment type and PI indices corresponding to the specified stations.
set_stake_xy(self)	Sets the xy coordinates for all station stakes assigned to the alignment.
station_coordinates(self, coordinates)	Finds the (station, offset) or (station, offset, z) coordinates for the input global coordinates.
tangent_ordinates(self)	Returns an array of tangent ordinates corresponding to each PI in the shape (N,).