gshhs.lua
NAME
gshhs
FUNCTION
gshhs(tbl)
NOTES
Reads map data from a GSHHS file.
INPUTS
tbl - table that may has keys of
file - file that contains GSHHS data
xmin - start longitude (default = 0)
xmax - end longitude (default = 360)
ymin - start latitude (default = -90)
ymax - end latitude (default = 90)
z - the z-value for 3D plot (default = 0)
category - land, lake, island, or pond (default = land)
OUTPUTS
an array object that contains longitude, latitude, and z-value
Example:
arr = gshhs({file = "gshhs_c", xmin = 120, xmax = 180, ymin = 10, ymax = 80})
SOURCE
function gshhs(tbl)
local xmin = 0
if (tbl.xmin) then xmin = tbl.xmin; end
local xmax = 360
if (tbl.xmax) then xmax = tbl.xmax; end
local ymin = -90
if (tbl.ymin) then ymin = tbl.ymin; end
local ymax = 90
if (tbl.ymax) then ymax = tbl.ymax; end
local category = "land"
if (tbl.category) then category = tbl.category; end
local z = 0
if (tbl.z) then z = tbl.z; end
local arr, bio = zeUtl.new("double", "bio")
bio:open(tbl.file)
bio:gshhs(category, xmin, xmax, ymin, ymax, arr)
arr:insert(2, z)
return arr
end