Add write_w90_hrdat (#14)

src/w90/hr.jl

@@ -1,4 +1,4 @@
-export read_w90_hrdat
+export read_w90_hrdat, write_w90_hrdat
 
 """
     $(SIGNATURES)
@@ -36,3 +36,59 @@ function read_w90_hrdat(filename::AbstractString)
         return (; Rvectors, Rdegens, H, header)
     end
 end
+
+"""
+    $(SIGNATURES)
+
+Write `prefix_hr.dat`.
+
+# Keyword arguments
+See the return values of [`read_w90_hrdat`](@ref).
+"""
+function write_w90_hrdat(
+    filename::AbstractString;
+    Rvectors::AbstractVector,
+    Rdegens::AbstractVector,
+    H::AbstractVector,
+    header=default_header(),
+)
+    n_Rvecs = length(H)
+    @assert n_Rvecs > 0 "empty H"
+    n_wann = size(H[1], 1)
+    @info "Writing hr.dat file" filename header n_wann n_Rvecs
+
+    return open(filename, "w") do io
+        println(io, strip(header))
+        @printf(io, "%d\n", n_wann)
+        @printf(io, "%d\n", n_Rvecs)
+
+        n_columns = 15
+        for (iR, degen) in enumerate(Rdegens)
+            @printf(io, "%5d", degen)
+            if mod(iR, n_columns) == 0
+                println(io)
+            end
+        end
+        if mod(n_Rvecs, n_columns) != 0
+            println(io)
+        end
+
+        for iR in 1:n_Rvecs
+            for n in 1:n_wann
+                for m in 1:n_wann
+                    reH = real(H[iR][m, n])
+                    imH = imag(H[iR][m, n])
+                    @printf(
+                        io,
+                        " %4d %4d %4d %4d %4d %11.6f %11.6f\n",
+                        Rvectors[iR]...,
+                        m,
+                        n,
+                        reH,
+                        imH
+                    )
+                end
+            end
+        end
+    end
+end

test/w90/hr.jl

@@ -25,3 +25,18 @@ end
         @test hrdat_ws[p] ≈ hrdat[p]
     end
 end
+
+@testitem "write hr" begin
+    using LazyArtifacts
+    hrdat = read_w90_hrdat(artifact"Si2_valence/reference/WS/Si2_valence_hr.dat")
+
+    tmpfile = tempname(; cleanup=true)
+    write_w90_hrdat(tmpfile; hrdat...)
+    hrdat2 = read_w90_hrdat(tmpfile)
+
+    @test keys(hrdat) == keys(hrdat2)
+    for (k, v) in pairs(hrdat)
+        k == :header && continue
+        @test hrdat2[k] == v
+    end
+end