puts "========"
puts "OCC23171"
puts "========"
puts ""
##################################
# Got wrong result after stitching
##################################

catch {pload XDE}

igesread [locate_data_file bug23171_tube_surf.igs] s *
sewing r 0.1 s

checkshape r

checknbshapes r -vertex 4 -edge 6

checkmaxtol r -min_tol 0.2
