Divide a LINESTRING with a list of LINESTRING
Question:
I’m searching a solution to divide Main Line with more than one overlapped lines. In this example I’ve four lines (I’ve applied an offset on Line 1, Line 2 and Line 3 in this chart to facilitate reading):
Below the lines:
from shapely import wkt
main_line = wkt.loads('LINESTRING (461179.6655721677 4507148.788223281, 461217.56786209624 4507181.537033379, 461236.3280996226 4507194.537878151, 461241.7247760045 4507197.640095252, 461258.8379542616 4507210.660701941, 461261.9432857035 4507219.791508417, 461270.90091201715 4507254.590010401, 461271.56385885156 4507303.918307676, 461273.67536588735 4507318.460376316, 461286.2322009634 4507358.346460313, 461302.55653224624 4507403.197152592, 461365.2492823085 4507485.060388609, 461480.4983426857 4507548.512415529, 461580.7367309019 4507618.493483591)')
line_1 = wkt.loads('LINESTRING (461179.6655721677 4507148.788223281, 461217.56786209624 4507181.537033379, 461236.3280996226 4507194.537878151, 461241.7247760045 4507197.640095252, 461258.8379542616 4507210.660701941, 461261.9432857035 4507219.791508417, 461270.90091201715 4507254.590010401, 461271.56385885156 4507303.918307676, 461273.67536588735 4507318.460376316, 461286.2322009634 4507358.346460313, 461302.55653224624 4507403.197152592)')
line_2 = wkt.loads('LINESTRING (461179.6655721677 4507148.788223281, 461217.56786209624 4507181.537033379, 461236.3280996226 4507194.537878151, 461241.7247760045 4507197.640095252, 461258.8379542616 4507210.660701941, 461261.9432857035 4507219.791508417, 461270.90091201715 4507254.590010401, 461271.56385885156 4507303.918307676, 461273.67536588735 4507318.460376316, 461286.2322009634 4507358.346460313, 461302.55653224624 4507403.197152592, 461365.2492823085 4507485.060388609)')
line_3 = wkt.loads('LINESTRING (461179.6655721677 4507148.788223281, 461217.56786209624 4507181.537033379, 461236.3280996226 4507194.537878151, 461241.7247760045 4507197.640095252, 461258.8379542616 4507210.660701941, 461261.9432857035 4507219.791508417, 461270.90091201715 4507254.590010401, 461271.56385885156 4507303.918307676, 461273.67536588735 4507318.460376316, 461286.2322009634 4507358.346460313, 461302.55653224624 4507403.197152592, 461365.2492823085 4507485.060388609, 461480.4983426857 4507548.512415529)')
I don’t know how many lines I’ve, in staging I will have a list. Looking the image above Main Line will be divided into 4 parts, but I’m little bit confused on how I can do this. I’ve used the code below hoping into a brilliant idea but without fortune.
line_list = [line_1, line_2, line_3]
diff_list = []
first_line_length = line_list[0].length
for line in line_list:
line_length = line.length
if line_length != first_line_length:
diff = main_line.symmetric_difference(line)
diff_list.append(diff)
fig, ax = plt.subplots(figsize=(10, 10))
ax.set_xlabel('X coordinate', fontsize=15)
ax.set_ylabel('Y coordinate', fontsize=15)
plt.plot(*main_line.xy, label='Main Line', color='blue')
plt.plot(*line_1.parallel_offset(distance=5).xy, label='Line 1', color='green')
plt.plot(*line_2.parallel_offset(distance=10).xy, label='Line 2', color='red')
plt.plot(*line_3.parallel_offset(distance=15).xy, label='Line 3', color='violet')
plt.plot(*diff_list[0].parallel_offset(distance=-5).xy, label='Diff Line 1', color='green')
plt.plot(*diff_list[1].parallel_offset(distance=-10).xy, label='Diff Line 2', color='red')
plt.legend()
plt.show()
In brief, if I have n lines shortest than a main line, I would like to divide that main line in n+1 parts.
Answers:
Assuming the exercise is as the one presented, (all lines have the same origin), modify your code to do the following:
- Order lines in descending length order, from the longest to the shortest (being the main line the longest)
- Then iterate the line list and do the symmetric difference only with the line following (main – line1, line1 – line2 and line2- line3).
- The segments will be the differences calculated in Step 2 plus line3.
Being Line1 longer than line2 and Line2 longer than line3
from shapely import wkt
from matplotlib import pyplot as plt
main_line = wkt.loads('LINESTRING (461179.6655721677 4507148.788223281, 461217.56786209624 4507181.537033379, 461236.3280996226 4507194.537878151, 461241.7247760045 4507197.640095252, 461258.8379542616 4507210.660701941, 461261.9432857035 4507219.791508417, 461270.90091201715 4507254.590010401, 461271.56385885156 4507303.918307676, 461273.67536588735 4507318.460376316, 461286.2322009634 4507358.346460313, 461302.55653224624 4507403.197152592, 461365.2492823085 4507485.060388609, 461480.4983426857 4507548.512415529, 461580.7367309019 4507618.493483591)')
line_1 = wkt.loads('LINESTRING (461179.6655721677 4507148.788223281, 461217.56786209624 4507181.537033379, 461236.3280996226 4507194.537878151, 461241.7247760045 4507197.640095252, 461258.8379542616 4507210.660701941, 461261.9432857035 4507219.791508417, 461270.90091201715 4507254.590010401, 461271.56385885156 4507303.918307676, 461273.67536588735 4507318.460376316, 461286.2322009634 4507358.346460313, 461302.55653224624 4507403.197152592)')
line_2 = wkt.loads('LINESTRING (461179.6655721677 4507148.788223281, 461217.56786209624 4507181.537033379, 461236.3280996226 4507194.537878151, 461241.7247760045 4507197.640095252, 461258.8379542616 4507210.660701941, 461261.9432857035 4507219.791508417, 461270.90091201715 4507254.590010401, 461271.56385885156 4507303.918307676, 461273.67536588735 4507318.460376316, 461286.2322009634 4507358.346460313, 461302.55653224624 4507403.197152592, 461365.2492823085 4507485.060388609)')
line_3 = wkt.loads('LINESTRING (461179.6655721677 4507148.788223281, 461217.56786209624 4507181.537033379, 461236.3280996226 4507194.537878151, 461241.7247760045 4507197.640095252, 461258.8379542616 4507210.660701941, 461261.9432857035 4507219.791508417, 461270.90091201715 4507254.590010401, 461271.56385885156 4507303.918307676, 461273.67536588735 4507318.460376316, 461286.2322009634 4507358.346460313, 461302.55653224624 4507403.197152592, 461365.2492823085 4507485.060388609, 461480.4983426857 4507548.512415529)')
line_list = [main_line,line_1, line_2, line_3]
line_list.sort(key=lambda x: x.length, reverse=True)
diff_list = []
for ix in range(len(line_list)-1):
#for line in line_list:
lineA=line_list[ix]
lineB=line_list[ix+1]
#line_length = line.length
#if line_length != first_line_length:
diff = lineA.symmetric_difference(lineB)
diff_list.append(diff)
fig, ax = plt.subplots(figsize=(10, 10))
ax.set_xlabel('X coordinate', fontsize=15)
ax.set_ylabel('Y coordinate', fontsize=15)
plt.plot(*main_line.xy, label='Main Line', color='blue')
plt.plot(*line_list[1].parallel_offset(distance=5).xy, label='Line 1', color='green')
plt.plot(*line_list[2].parallel_offset(distance=10).xy, label='Line 2', color='red')
plt.plot(*line_list[3].parallel_offset(distance=15).xy, label='Line 3', color='violet')
plt.plot(*diff_list[0].parallel_offset(distance=-5).xy, label='Diff main - Line 1', color='blue')
plt.plot(*diff_list[1].parallel_offset(distance=-10).xy, label='Diff Line 1 - Line 2', color='green')
plt.plot(*diff_list[2].parallel_offset(distance=-15).xy, label='Diff Line 2 - Line 3', color='red')
plt.legend()
plt.show()
I’m searching a solution to divide Main Line with more than one overlapped lines. In this example I’ve four lines (I’ve applied an offset on Line 1, Line 2 and Line 3 in this chart to facilitate reading):
Below the lines:
from shapely import wkt
main_line = wkt.loads('LINESTRING (461179.6655721677 4507148.788223281, 461217.56786209624 4507181.537033379, 461236.3280996226 4507194.537878151, 461241.7247760045 4507197.640095252, 461258.8379542616 4507210.660701941, 461261.9432857035 4507219.791508417, 461270.90091201715 4507254.590010401, 461271.56385885156 4507303.918307676, 461273.67536588735 4507318.460376316, 461286.2322009634 4507358.346460313, 461302.55653224624 4507403.197152592, 461365.2492823085 4507485.060388609, 461480.4983426857 4507548.512415529, 461580.7367309019 4507618.493483591)')
line_1 = wkt.loads('LINESTRING (461179.6655721677 4507148.788223281, 461217.56786209624 4507181.537033379, 461236.3280996226 4507194.537878151, 461241.7247760045 4507197.640095252, 461258.8379542616 4507210.660701941, 461261.9432857035 4507219.791508417, 461270.90091201715 4507254.590010401, 461271.56385885156 4507303.918307676, 461273.67536588735 4507318.460376316, 461286.2322009634 4507358.346460313, 461302.55653224624 4507403.197152592)')
line_2 = wkt.loads('LINESTRING (461179.6655721677 4507148.788223281, 461217.56786209624 4507181.537033379, 461236.3280996226 4507194.537878151, 461241.7247760045 4507197.640095252, 461258.8379542616 4507210.660701941, 461261.9432857035 4507219.791508417, 461270.90091201715 4507254.590010401, 461271.56385885156 4507303.918307676, 461273.67536588735 4507318.460376316, 461286.2322009634 4507358.346460313, 461302.55653224624 4507403.197152592, 461365.2492823085 4507485.060388609)')
line_3 = wkt.loads('LINESTRING (461179.6655721677 4507148.788223281, 461217.56786209624 4507181.537033379, 461236.3280996226 4507194.537878151, 461241.7247760045 4507197.640095252, 461258.8379542616 4507210.660701941, 461261.9432857035 4507219.791508417, 461270.90091201715 4507254.590010401, 461271.56385885156 4507303.918307676, 461273.67536588735 4507318.460376316, 461286.2322009634 4507358.346460313, 461302.55653224624 4507403.197152592, 461365.2492823085 4507485.060388609, 461480.4983426857 4507548.512415529)')
I don’t know how many lines I’ve, in staging I will have a list. Looking the image above Main Line will be divided into 4 parts, but I’m little bit confused on how I can do this. I’ve used the code below hoping into a brilliant idea but without fortune.
line_list = [line_1, line_2, line_3]
diff_list = []
first_line_length = line_list[0].length
for line in line_list:
line_length = line.length
if line_length != first_line_length:
diff = main_line.symmetric_difference(line)
diff_list.append(diff)
fig, ax = plt.subplots(figsize=(10, 10))
ax.set_xlabel('X coordinate', fontsize=15)
ax.set_ylabel('Y coordinate', fontsize=15)
plt.plot(*main_line.xy, label='Main Line', color='blue')
plt.plot(*line_1.parallel_offset(distance=5).xy, label='Line 1', color='green')
plt.plot(*line_2.parallel_offset(distance=10).xy, label='Line 2', color='red')
plt.plot(*line_3.parallel_offset(distance=15).xy, label='Line 3', color='violet')
plt.plot(*diff_list[0].parallel_offset(distance=-5).xy, label='Diff Line 1', color='green')
plt.plot(*diff_list[1].parallel_offset(distance=-10).xy, label='Diff Line 2', color='red')
plt.legend()
plt.show()
In brief, if I have n lines shortest than a main line, I would like to divide that main line in n+1 parts.
Assuming the exercise is as the one presented, (all lines have the same origin), modify your code to do the following:
- Order lines in descending length order, from the longest to the shortest (being the main line the longest)
- Then iterate the line list and do the symmetric difference only with the line following (main – line1, line1 – line2 and line2- line3).
- The segments will be the differences calculated in Step 2 plus line3.
Being Line1 longer than line2 and Line2 longer than line3
from shapely import wkt
from matplotlib import pyplot as plt
main_line = wkt.loads('LINESTRING (461179.6655721677 4507148.788223281, 461217.56786209624 4507181.537033379, 461236.3280996226 4507194.537878151, 461241.7247760045 4507197.640095252, 461258.8379542616 4507210.660701941, 461261.9432857035 4507219.791508417, 461270.90091201715 4507254.590010401, 461271.56385885156 4507303.918307676, 461273.67536588735 4507318.460376316, 461286.2322009634 4507358.346460313, 461302.55653224624 4507403.197152592, 461365.2492823085 4507485.060388609, 461480.4983426857 4507548.512415529, 461580.7367309019 4507618.493483591)')
line_1 = wkt.loads('LINESTRING (461179.6655721677 4507148.788223281, 461217.56786209624 4507181.537033379, 461236.3280996226 4507194.537878151, 461241.7247760045 4507197.640095252, 461258.8379542616 4507210.660701941, 461261.9432857035 4507219.791508417, 461270.90091201715 4507254.590010401, 461271.56385885156 4507303.918307676, 461273.67536588735 4507318.460376316, 461286.2322009634 4507358.346460313, 461302.55653224624 4507403.197152592)')
line_2 = wkt.loads('LINESTRING (461179.6655721677 4507148.788223281, 461217.56786209624 4507181.537033379, 461236.3280996226 4507194.537878151, 461241.7247760045 4507197.640095252, 461258.8379542616 4507210.660701941, 461261.9432857035 4507219.791508417, 461270.90091201715 4507254.590010401, 461271.56385885156 4507303.918307676, 461273.67536588735 4507318.460376316, 461286.2322009634 4507358.346460313, 461302.55653224624 4507403.197152592, 461365.2492823085 4507485.060388609)')
line_3 = wkt.loads('LINESTRING (461179.6655721677 4507148.788223281, 461217.56786209624 4507181.537033379, 461236.3280996226 4507194.537878151, 461241.7247760045 4507197.640095252, 461258.8379542616 4507210.660701941, 461261.9432857035 4507219.791508417, 461270.90091201715 4507254.590010401, 461271.56385885156 4507303.918307676, 461273.67536588735 4507318.460376316, 461286.2322009634 4507358.346460313, 461302.55653224624 4507403.197152592, 461365.2492823085 4507485.060388609, 461480.4983426857 4507548.512415529)')
line_list = [main_line,line_1, line_2, line_3]
line_list.sort(key=lambda x: x.length, reverse=True)
diff_list = []
for ix in range(len(line_list)-1):
#for line in line_list:
lineA=line_list[ix]
lineB=line_list[ix+1]
#line_length = line.length
#if line_length != first_line_length:
diff = lineA.symmetric_difference(lineB)
diff_list.append(diff)
fig, ax = plt.subplots(figsize=(10, 10))
ax.set_xlabel('X coordinate', fontsize=15)
ax.set_ylabel('Y coordinate', fontsize=15)
plt.plot(*main_line.xy, label='Main Line', color='blue')
plt.plot(*line_list[1].parallel_offset(distance=5).xy, label='Line 1', color='green')
plt.plot(*line_list[2].parallel_offset(distance=10).xy, label='Line 2', color='red')
plt.plot(*line_list[3].parallel_offset(distance=15).xy, label='Line 3', color='violet')
plt.plot(*diff_list[0].parallel_offset(distance=-5).xy, label='Diff main - Line 1', color='blue')
plt.plot(*diff_list[1].parallel_offset(distance=-10).xy, label='Diff Line 1 - Line 2', color='green')
plt.plot(*diff_list[2].parallel_offset(distance=-15).xy, label='Diff Line 2 - Line 3', color='red')
plt.legend()
plt.show()