Finish s

src/cells.jl

@@ -1,5 +1,5 @@
 import Base: getindex, push!, append!, show, length, size
-export SpiceIntCell, SpiceDoubleCell, SpiceCharCell, appnd, push!, append!, card, length, copy
+export SpiceIntCell, SpiceDoubleCell, SpiceCharCell, appnd, push!, append!, card, length, copy, size_c
 
 const CTRLSZ = 6
 
@@ -189,3 +189,10 @@ function Base.copy(cell::SpiceCharCell)
     copy
 end
 
+"""
+    size_c(cell::SpiceCell)
+
+Returns the maximum number of elements that `cell` can hold.
+"""
+size_c(cell) = cell.cell.size
+

src/g.jl

@@ -2,6 +2,7 @@ export
     gcpool,
     gdpool,
     georec,
+    getelm,
     getfov,
     gfpa,
     gfpa!,
@@ -102,6 +103,37 @@ function georec(lon, lat, alt, re, f)
     rectan
 end
 
+"""
+    getelm(frstyr, lines)
+
+Given the "lines" of a two-line element set, parse the lines and return the elements in units
+suitable for use in SPICE software.
+
+### Arguments ###
+
+- `frstyr`: Year of earliest representable two-line elements
+- `lines`: A pair of "lines" containing two-line elements
+
+### Output ###
+
+- `epoch`: The epoch of the elements in seconds past J2000
+- `elems`: The elements converted to SPICE units
+
+### References ###
+
+- [NAIF Documentation](https://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/getelm_c.html)
+"""
+function getelm(frstyr, lines)
+    array, _, lineln = chararray(lines)
+    epoch = Ref{SpiceDouble}()
+    elems = Array{SpiceDouble}(undef, 10)
+    ccall((:getelm_c, libcspice), Cvoid,
+          (SpiceInt, SpiceInt, Ptr{SpiceChar}, Ref{SpiceDouble}, Ptr{SpiceDouble}),
+          frstyr, lineln, array, epoch, elems)
+    handleerror()
+    epoch[], elems
+end
+
 """
     getfov(instid, room=10, shapelen=128, framelen=128)
 

src/l.jl

@@ -173,13 +173,13 @@ Returns an array of surface points
 """
 function latsrf(method, target, et, fixref, lonlat)
     npts = length(lonlat)
-    lonlat = permutedims(hcat(collect.(lonlat)...))
-    srfpts = Matrix{SpiceDouble}(undef, npts, 3)
+    lonlat = array_to_cmatrix(lonlat, n=2)
+    srfpts = Matrix{SpiceDouble}(undef, 3, npts)
     ccall((:latsrf_c, libcspice), Cvoid,
           (Cstring, Cstring, SpiceDouble, Cstring, SpiceInt, Ptr{SpiceDouble}, Ptr{SpiceDouble}),
           method, target, et, fixref, npts, lonlat, srfpts)
     handleerror()
-    [srfpts[i, :] for i in 1:size(srfpts,1)]
+    cmatrix_to_array(srfpts)
 end
 
 _lcase(in) = _lcase(in,length(in)+1)