def feat_to_pnt(inShp, outPnt, epsg=None):
"""
Get Centroid from each line in a PolyLine Feature Class
"""
import os
from osgeo import ogr
from gasp.prop.ff import drv_name
from gasp.mng.fld import ogr_copy_fields
from gasp.mng.fld import lst_fld
# TODO: check if geometry is correct
# Open data
polyData = ogr.GetDriverByName(drv_name(outPnt)).Open(inShp)
polyLyr = polyData.GetLayer()
# Get SRS for the output
if not epsg:
from gasp.prop.prj import get_shp_sref
srs = get_shp_sref(polyLyr)
else:
from gasp.prop.prj import get_sref_from_epsg
srs = get_sref_from_epsg(epsg)
# Create output
pntData = ogr.GetDriverByName(drv_name(outPnt)).CreateDataSource(outPnt)
pntLyr = pntData.CreateLayer(os.path.splitext(os.path.basename(outPnt))[0],
srs,
geom_type=ogr.wkbPoint)
# Copy fields from input to output
fields = lst_fld(polyLyr)
ogr_copy_fields(polyLyr, pntLyr)
pntLyrDefn = pntLyr.GetLayerDefn()
for feat in polyLyr:
geom = feat.GetGeometryRef()
pnt = geom.Centroid()
new_feat = ogr.Feature(pntLyrDefn)
new_feat.SetGeometry(pnt)
for fld in fields:
new_feat.SetField(fld, feat.GetField(fld))
pntLyr.CreateFeature(new_feat)
new_feat.Destroy()
del pntLyr
del polyLyr
pntData.Destroy()
polyData.Destroy()
return outPnt
def split_whr_attrIsTrue(osm_fc,
outputfolder,
fields=None,
sel_fields=None,
basename=None):
"""
For each field in osm table or in fields, creates a new feature class
where the field attribute is not empty
"""
import os
from gasp.mng.fld import lst_fld
from gasp.anls.exct import sel_by_attr
# List table fields
tbl_fields = fields if fields else lst_fld(osm_fc)
if type(tbl_fields) == str or type(tbl_fields) == unicode:
tbl_fields = [tbl_fields]
if sel_fields:
sel_fields.append('geometry')
aux = 1
else:
aux = 0
# Export each field in data
outFilename = '{}.shp' if not basename else basename + '_{}.shp'
for fld in tbl_fields:
a = 0
if not aux:
sel_fields = ['geometry', fld]
else:
if fld not in sel_fields:
sel_fields.append(fld)
a += 1
sel_by_attr(
osm_fc,
"SELECT {flds} FROM {t} WHERE {f}<>''".format(
f=fld,
t=os.path.splitext(os.path.basename(osm_fc))[0],
flds=', '.join(sel_fields)),
os.path.join(
outputfolder,
outFilename.format(fld if fld.islower() else fld.lower())),
api_gis='ogr')
if a:
sel_fields.remove(fld)
def splitShp_by_range(shp, nrFeat, outFolder):
"""
Split one feature class by range
"""
import os
from gasp.oss import get_filename, get_fileformat
from gasp.prop.feat import feat_count
from gasp.mng.fld import lst_fld
from gasp.anls.exct import sel_by_attr
rowsN = feat_count(shp, gisApi='ogr')
nrShp = int(rowsN / float(nrFeat)) + 1 if nrFeat != rowsN else 1
fields = lst_fld(shp)
offset = 0
exportedShp = []
for i in range(nrShp):
outShp = sel_by_attr(
shp,
"SELECT {cols}, geometry FROM {t} ORDER BY {cols} LIMIT {l} OFFSET {o}"
.format(t=os.path.splitext(os.path.basename(shp))[0],
l=str(nrFeat),
o=str(offset),
cols=", ".join(fields)),
os.path.join(
outFolder, "{}_{}{}".format(get_filename(shp, forceLower=True),
str(i), get_fileformat(shp))),
api_gis='ogr')
exportedShp.append(outShp)
offset += nrFeat
return exportedShp
def eachfeat_to_newshp(inShp, outFolder, epsg=None):
"""
Export each feature in inShp to a new/single File
"""
import os
from osgeo import ogr
from gasp.prop.ff import drv_name
from gasp.prop.feat import get_geom_type
from gasp.mng.fld import lst_fld
from gasp.mng.fld import ogr_copy_fields
from gasp.oss import get_fileformat, get_filename
inDt = ogr.GetDriverByName(drv_name(inShp)).Open(inShp)
lyr = inDt.GetLayer()
# Get SRS for the output
if not epsg:
from gasp.prop.prj import get_shp_sref
srs = get_shp_sref(lyr)
else:
from gasp.prop.prj import get_sref_from_epsg
srs = get_sref_from_epsg(epsg)
# Get fields name
fields = lst_fld(lyr)
# Get Geometry type
geomCls = get_geom_type(inShp, gisApi='ogr', name=None, py_cls=True)
# Read features and create a new file for each feature
RESULT_SHP = []
for feat in lyr:
# Create output
newShp = os.path.join(
outFolder, "{}_{}{}".format(get_filename(inShp),
str(feat.GetFID()),
get_fileformat(inShp)))
newData = ogr.GetDriverByName(
drv_name(newShp)).CreateDataSource(newShp)
newLyr = newData.CreateLayer(str(get_filename(newShp)),
srs,
geom_type=geomCls)
# Copy fields from input to output
ogr_copy_fields(lyr, newLyr)
newLyrDefn = newLyr.GetLayerDefn()
# Create new feature
newFeat = ogr.Feature(newLyrDefn)
# Copy geometry
geom = feat.GetGeometryRef()
newFeat.SetGeometry(geom)
# Set fields attributes
for fld in fields:
newFeat.SetField(fld, feat.GetField(fld))
# Save feature
newLyr.CreateFeature(newFeat)
newFeat.Destroy()
del newLyr
newData.Destroy()
RESULT_SHP.append(newShp)
return RESULT_SHP