stokes I works with only 1 par hand

Author: aplavin

Project.toml

@@ -1,7 +1,7 @@
 name = "VLBIData"
 uuid = "679fc9cc-3e84-11e9-251b-cbd013bd8115"
 authors = ["Alexander Plavin <alexander@plav.in>"]
-version = "0.5.10"
+version = "0.5.11"
 
 [deps]
 AccessorsExtra = "33016aad-b69d-45be-9359-82a41f556fd4"

src/polarizedtypes.jl

@@ -22,8 +22,8 @@ function uvtable_values_to(::Type{IPol}, uvtbl)
 	grs = @p uvtbl group_vg((;_.datetime, _.freq_spec, _.spec))
 	return map(grs) do gr
 		par_hands = @p gr filter(x -> is_parallel_hands(x.stokes))
-		length(par_hands) == 2 || error("expected 2 parallel-hand Stokes per group, got $(length(par_hands))")
-		val = sum(x -> x.value, par_hands) / 2
+		length(par_hands) ∈ (1, 2) || error("expected 1 or 2 parallel-hand Stokes per group, got $(length(par_hands))")
+		val = mean(x -> x.value, par_hands)
 		@p let
 			first(gr)
 			@set __.value = val

test/runtests.jl

@@ -278,8 +278,31 @@ end
     ipol_lin = VLBI.uvtable_values_to(IPol, uvtbl_lin)
     @test ipol_lin[1].value == 5.0
 
-    # IPol: error when only 1 parallel hand
-    @test_throws "expected 2 parallel-hand" VLBI.uvtable_values_to(IPol, uvtbl_err)
+    # IPol: from single parallel hand (RR only)
+    uvtbl_single_rr = [
+        (datetime=1, freq_spec=100.0, spec=1, stokes=:RR, value=11.0),
+        (datetime=1, freq_spec=100.0, spec=1, stokes=:LR, value=12.0),
+        (datetime=1, freq_spec=100.0, spec=1, stokes=:RL, value=13.0),
+    ]
+    ipol_single = VLBI.uvtable_values_to(IPol, uvtbl_single_rr)
+    @test length(ipol_single) == 1
+    @test ipol_single[1].value == 11.0
+    @test !haskey(ipol_single[1], :stokes)
+
+    # IPol: from single parallel hand (LL only)
+    uvtbl_single_ll = [
+        (datetime=1, freq_spec=100.0, spec=1, stokes=:LL, value=7.0),
+    ]
+    ipol_single_ll = VLBI.uvtable_values_to(IPol, uvtbl_single_ll)
+    @test length(ipol_single_ll) == 1
+    @test ipol_single_ll[1].value == 7.0
+
+    # IPol: error when no parallel hands
+    uvtbl_no_par = [
+        (datetime=1, freq_spec=100.0, spec=1, stokes=:LR, value=12.0),
+        (datetime=1, freq_spec=100.0, spec=1, stokes=:RL, value=13.0),
+    ]
+    @test_throws "expected 1 or 2 parallel-hand" VLBI.uvtable_values_to(IPol, uvtbl_no_par)
 end
 
 @testitem "_" begin