" where cat=" + str(i + 1))
# Points
cur.execute("update streams set x1=" + str(points_in_streams[i][0].x) +
" where cat=" + str(i + 1))
cur.execute("update streams set y1=" + str(points_in_streams[i][0].y) +
" where cat=" + str(i + 1))
cur.execute("update streams set x2=" +
str(points_in_streams[i][-1].x) + " where cat=" +
str(i + 1))
cur.execute("update streams set y2=" +
str(points_in_streams[i][-1].y) + " where cat=" +
str(i + 1))
print i
#streamsTopo.write()
streamsTopo.table.conn.commit()
streamsTopo.build()
# Note on adding columns
# sch.table.columns.add('elevation','double precision')
# THEN:
# 5. Every line should have
"""
# Get line segment endpoints
# xy1: UPSTREAM
# xy2: DOWNSTREAM
v.db_addcolumn(map='streams', columns='x1 double precision, y1 double precision, x2 double precision, y2 double precision')
v.to_db(map='streams', option='start', columns='x1, y1')
v.to_db(map='streams', option='end', columns='x2, y2')
"""
"""
def main():
"""
Links each river segment to the next downstream segment in a tributary
network by referencing its category (cat) number in a new column. "0"
means that the river exits the map.
"""
options, flags = gscript.parser()
streams = options['map']
x1 = options['upstream_easting_column']
y1 = options['upstream_northing_column']
x2 = options['downstream_easting_column']
y2 = options['downstream_northing_column']
streamsTopo = VectorTopo(streams)
#streamsTopo.build()
# 1. Get vectorTopo
streamsTopo.open(mode='rw')
"""
points_in_streams = []
cat_of_line_segment = []
# 2. Get coordinates
for row in streamsTopo:
cat_of_line_segment.append(row.cat)
if type(row) == vector.geometry.Line:
points_in_streams.append(row)
"""
# 3. Coordinates of points: 1 = start, 2 = end
try:
streamsTopo.table.columns.add(x1, 'double precision')
except:
pass
try:
streamsTopo.table.columns.add(y1, 'double precision')
except:
pass
try:
streamsTopo.table.columns.add(x2, 'double precision')
except:
pass
try:
streamsTopo.table.columns.add(y2, 'double precision')
except:
pass
try:
streamsTopo.table.columns.add('tostream', 'int')
except:
pass
streamsTopo.table.conn.commit()
# Is this faster than v.to.db?
"""
cur = streamsTopo.table.conn.cursor()
for i in range(len(points_in_streams)):
cur.execute("update streams set x1="+str(points_in_streams[i][0].x)+" where cat="+str(cat_of_line_segment[i]))
cur.execute("update streams set y1="+str(points_in_streams[i][0].y)+" where cat="+str(cat_of_line_segment[i]))
cur.execute("update streams set x2="+str(points_in_streams[i][-1].x)+" where cat="+str(cat_of_line_segment[i]))
cur.execute("update streams set y2="+str(points_in_streams[i][-1].y)+" where cat="+str(cat_of_line_segment[i]))
streamsTopo.table.conn.commit()
streamsTopo.build()
"""
# v.to.db Works more consistently, at least
streamsTopo.close()
v.to_db(map=streams, option='start', columns=x1 + ',' + y1)
v.to_db(map=streams, option='end', columns=x2 + ',' + y2)
# 4. Read in and save the start and end coordinate points
colNames = np.array(vector_db_select(streams)['columns'])
colValues = np.array(vector_db_select(streams)['values'].values())
cats = colValues[:,
colNames == 'cat'].astype(int).squeeze() # river number
xy1 = colValues[:, (colNames == 'x1') + (colNames == 'y1')].astype(
float) # upstream
xy2 = colValues[:, (colNames == 'x2') + (colNames == 'y2')].astype(
float) # downstream
# 5. Build river network
tocat = []
for i in range(len(cats)):
tosegment_mask = np.prod(xy1 == xy2[i], axis=1)
if np.sum(tosegment_mask) == 0:
tocat.append(0)
else:
tocat.append(cats[tosegment_mask.nonzero()[0][0]])
tocat = np.asarray(tocat).astype(int)
# This gives us a set of downstream-facing adjacencies.
# We will update the database with it.
streamsTopo.build()
streamsTopo.open('rw')
cur = streamsTopo.table.conn.cursor()
# Default to 0 if no stream flows to it
cur.execute("update " + streams + " set tostream=0")
for i in range(len(tocat)):
cur.execute("update " + streams + " set tostream=" + str(tocat[i]) +
" where cat=" + str(cats[i]))
streamsTopo.table.conn.commit()
#streamsTopo.build()
streamsTopo.close()
gscript.message('')
gscript.message(
'Drainage topology built. Check "tostream" column for the downstream cat.'
)
gscript.message('A cat value of 0 indicates the downstream-most segment.')
gscript.message('')
def main():
"""
Links each river segment to the next downstream segment in a tributary
network by referencing its category (cat) number in a new column. "0"
means that the river exits the map.
"""
options, flags = gscript.parser()
streams = options['streams']
streamsTopo = VectorTopo(streams)
streamsTopo.build()
# Is this faster than v.to.db?
# Works more consistently, at least
v.to_db(map=streams, option='start', columns='x1,y1')
v.to_db(map=streams, option='end', columns='x2,y2')
# 1. Get vectorTopo
streamsTopo.open(mode='rw')
points_in_streams = []
cat_of_line_segment = []
"""
# 2. Get coordinates
for row in streamsTopo:
cat_of_line_segment.append(row.cat)
if type(row) == vector.geometry.Line:
points_in_streams.append(row)
# 3. Coordinates of points: 1 = start, 2 = end
try:
streamsTopo.table.columns.add('x1','double precision')
except:
pass
try:
streamsTopo.table.columns.add('y1','double precision')
except:
pass
try:
streamsTopo.table.columns.add('x2','double precision')
except:
pass
try:
streamsTopo.table.columns.add('y2','double precision')
except:
pass
try:
streamsTopo.table.columns.add('tostream','int')
except:
pass
#streamsTopo.table.conn.commit()
#streamsTopo.build()
#streamsTopo.close()
"""
cur = streamsTopo.table.conn.cursor()
for i in range(len(points_in_streams)):
cur.execute("update streams set x1=" + str(points_in_streams[i][0].x) +
" where cat=" + str(cat_of_line_segment[i]))
cur.execute("update streams set y1=" + str(points_in_streams[i][0].y) +
" where cat=" + str(cat_of_line_segment[i]))
cur.execute("update streams set x2=" +
str(points_in_streams[i][-1].x) + " where cat=" +
str(cat_of_line_segment[i]))
cur.execute("update streams set y2=" +
str(points_in_streams[i][-1].y) + " where cat=" +
str(cat_of_line_segment[i]))
streamsTopo.table.conn.commit()
streamsTopo.build()
colNames = np.array(vector_db_select('streams')['columns'])
colValues = np.array(vector_db_select('streams')['values'].values())
cats = colValues[:,
colNames == 'cat'].astype(int).squeeze() # river number
print colValues
xy1 = colValues[:, (colNames == 'x1') + (colNames == 'y1')].astype(
float) # upstream
xy2 = colValues[:, (colNames == 'x2') + (colNames == 'y2')].astype(
float) # downstream
# Build river network
tocat = []
for i in range(len(cats)):
tosegment_mask = np.prod(xy1 == xy2[i], axis=1)
if np.sum(tosegment_mask) == 0:
tocat.append(0)
else:
tocat.append(cats[tosegment_mask.nonzero()[0][0]])
tocat = np.asarray(tocat).astype(int)
# This gives us a set of downstream-facing adjacencies.
# We will update the database with it.
streamsTopo.build()
streamsTopo.open('rw')
cur = streamsTopo.table.conn.cursor()
for i in range(len(tocat)):
cur.execute("update streams set tostream=" + str(tocat[i]) +
" where cat=" + str(cats[i]))
streamsTopo.table.conn.commit()
streamsTopo.build()
print ""
print "Done."
print ""
