How to smooth the Linestring after adding additional point?

Question

How to smooth the Linestring after adding additional point?

Rajan

2022年6月1日 15:52

Actually I am tracking vessel, where I am already having path, and current position. Now the trouble is, obviously the vessel will not be on same coordinates as provided in the path.So I want to connect the current coordinate with the path and willing get updated path.

I have already connected but the issue is with my way the vessel taking long route. Which will be problematic for ETA calculations.

Any suggestions? Also the image with map are from website just for understanding.

For example, the original route end something look like this:

After current position update it should like this:

But my way I am getting this:

Here is my data and code:

p = {'route': [{'path': [[51.51309, 0.4836599999999862],
     [51.512222970577746, 0.4838196951935174],
     [51.50817683327391, 0.4845649394298732],
     [51.50730980385166, 0.484724634623376],
     [51.490146683273906, 0.6260075894298893],
     [51.410052120577745, 1.285328045193495],
     [51.392889, 1.4266110000000083],
     [51.35695154999999, 1.4217484499999955],
     [51.18924344999999, 1.3990565500000116],
     [51.153306, 1.3941939999999988],
     [50.939489249999994, 0.8940607000000114],
     [49.94167775, -1.4398946999999964],
     [49.727861, -1.9400280000000123],
     [49.54469854999999, -2.366040450000014],
     [48.689940449999995, -4.354098550000003],
     [48.506778, -4.780111000000005],
     [47.68888635, -5.458406800000006],
     [43.87205865, -8.62378720000001],
     [43.054167, -9.30208300000001],
     [42.41353785, -9.331828900000005],
     [39.42393515, -9.47064309999999],
     [38.783306, -9.500389000000013],
     [38.5191851, -9.424647249999992],
     [37.286620899999996, -9.071185750000012],
     [37.0225, -8.995443999999992],
     [36.86918755, -8.487389949999994],
     [36.15372945, -6.116471050000001],
     [36.000417, -5.608417000000003],
     [36.139162799999994, -4.182775300000003],
     [36.7866432, 2.4702192999999966],
     [36.925389, 3.8958609999999965],
     [36.98901405, 4.773231850000002],
     [37.285930949999994, 8.867629149999999],
     [37.349556, 9.745000000000005],
     [37.31056005, 9.939120849999995],
     [37.12857895, 10.845018149999987],
     [37.089583, 11.039139000000006],
     [36.25582884999999, 14.171143199999989],
     [32.36497615, 28.787162800000004],
     [31.531222, 31.919167000000016],
     [31.486459599999996, 31.97396710000001],
     [31.2775684, 32.22970090000001],
     [31.232806, 32.284501000000006],
     [31.036959999999997, 32.32685409999999],
     [30.123011999999996, 32.52450189999999],
     [29.927166, 32.566855000000004],
     [27.339266099999996, 34.20131845],
     [15.262399899999998, 41.828814550000004],
     [12.6745, 43.463278],
     [12.6860083, 43.699777900000015],
     [12.7397137, 44.80344410000001],
     [12.751222, 45.03994399999999],
     [12.944847099999999, 45.588698300000004],
     [13.8484309, 48.14955170000002],
     [14.042056, 48.698306],
     [14.27693095, 49.22293100000002],
     [15.37301405, 51.67118099999999],
     [15.607889, 52.195806000000005],
     [15.81688895, 52.6194309],
     [16.79222205, 54.5963471],
     [17.001222, 55.019971999999996],
     [17.138847, 55.21973030000001],
     [17.781097, 56.151935699999996],
     [17.918722, 56.35169400000001],
     [18.080792799999998, 56.575119],
     [18.8371232, 57.61776900000001],
     [18.999194, 57.841194],
     [19.4823149, 58.13619825000001],
     [21.736879099999996, 59.51288475000001],
     [22.22, 59.80788899999999],
     [22.840945849999997, 59.31257655000002],
     [25.73869315, 57.00111844999998],
     [26.359639, 56.50580600000001],
     [26.160997649670072, 56.29158290493038],
     [25.234004681463745, 55.29187512793891],
     [25.035363331133816, 55.07765203286928],
     [25.00255, 55.10811000000001]],
    'type': 'SEA'}]}

from shapely.geometry import Point, LineString, Polygon
from shapely.ops import transform
from functools import partial
import pyproj
from shapely.ops import split
from itertools import chain


total_path=p['route'][0]['path'][1:-1] ##### Total path
total_line = LineString(total_path)


project = partial(
    pyproj.transform,
    pyproj.Proj('EPSG:4326'),
    pyproj.Proj('EPSG:32633'))
total_ls = transform(project, total_line)

total_distance = total_ls.length/1852   ######Tortal distance in NM
print(total_distance, Distance)


current_pin = (13.752724664396988, 56.42578125)
position = Point(current_pin)
all_points_coords = chain(total_line.coords,position.coords)
all_points = map(Point, all_points_coords)
new_line = LineString(sorted(all_points, key=total_line.project))
new_ls = transform(project, new_line)
new_distance = new_ls.length/1852

## remain distance from current position
remain = LineString(new_line.coords[new_line.coords[:].index(current_pin):]) 
remain = transform(project, remain)
r_distance = remain.length/1852

print(r_distance,remain distance)
print(r_distance/13)
new_ls

Topic python

Category Data Science

Rajan · Accepted Answer · 2022年6月1日 15:52

Here my main issue was the near points of my currentpoint. So I came with idea to reduce the unnecessary/near point without losing the shape of my line string. And than add the currentpoint.

Hence, I include this code to my existing code:

from itertools import chain

def process(input_list, threshold=2.3):
    combos = itertools.combinations(input_list, 2)
    points_to_remove = [point2 for point1, point2 in combos if math.dist(point1, point2)<=threshold]
    points_to_keep = [point for point in input_list if point not in points_to_remove]
    return points_to_keep

total_path = process(p['route'][0]['path'])

Output:

Still I am not having the best result, happy to hear any suggestion to improve my model.

Moreover, I need to get the remain distance at around 1025 NM with 78hr.but from my current code I've received 1164 NM with 89.5 hr.

How to smooth the Linestring after adding additional point?

About