shp2SLDF                 package:sp                 R Documentation

_C_o_n_v_e_r_t_e_r _f_u_n_c_t_i_o_n_s _t_o _b_u_i_l_d _S_p_a_t_i_a_l_L_i_n_e_s_D_a_t_a_F_r_a_m_e _o_b_j_e_c_t_s

_D_e_s_c_r_i_p_t_i_o_n:

     These functions show how to build converters from external formats
     to build SpatialLinesDataFrame objects: 'shp2SLDF' from '"arc"'
     type ESRI shapefiles read into '"Map"' objects using the
     'read.shape()' function in the maptools package; 'arcobj2SLDF'
     from the list returned by the 'get.arcdata' function in the
     RArcInfo package; and 'contourLines2SLDF' from the list returned
     by the 'contourLines' function in the graphics package (here the
     data frame is just the contour levels, with one Slines object made
     up of at least one Sline object per level).

_U_s_a_g_e:

     shp2SLDF(shp, proj4string = CRS(as.character(NA)))
     arcobj2SLDF(arc, proj4string=CRS(as.character(NA)))
     contourLines2SLDF(cL, proj4string=CRS(as.character(NA)))

_A_r_g_u_m_e_n_t_s:

     shp: a '"Map"' object returned by the 'read.shape()' function in
          the maptools package

     arc: a list returned by the 'get.arcdata' function in the RArcInfo
          package

      cL: a list returned by the 'contourLines' function in the
          graphics package

proj4string: Object of class '"CRS"'; see CRS-class

_V_a_l_u_e:

     A SpatialLinesDataFrame object

_A_u_t_h_o_r(_s):

     Roger Bivand; Edzer Pebesma

_S_e_e _A_l_s_o:

     SpatialLines-class

_E_x_a_m_p_l_e_s:

     data(lnsshp) # retrieved as: 
     # library(maptools)
     # lns <- read.shape(system.file("shapes/fylk-val.shp", package="maptools")[1])
     res <- shp2SLDF(lns)
     plot(res)
     invisible(title(""))
     data(co37_d90_arc) # retrieved as: 
     # library(RArcInfo)
     # fl <- "http://www.census.gov/geo/cob/bdy/co/co90e00/co37_d90_e00.zip"
     # download.file(fl, "co37_d90_e00.zip")
     # e00 <- zip.file.extract("co37_d90.e00", "co37_d90_e00.zip")
     # e00toavc(e00, "ncar")
     # arc <- get.arcdata(".", "ncar")
     res <- arcobj2SLDF(arc)
     plot(res)
     invisible(title(""))
     res <- contourLines2SLDF(contourLines(volcano))
     plot(res, col=terrain.colors(nrow(res@data)))
     invisible(title(""))

