Merge e4b7038 into 4c8047e

README.md

@@ -85,6 +85,11 @@ Distances
     <td>angular_diameter_dist(cosmo,&nbsp;z)</td>
     <td>Ratio of an object's proper transverse size (in Mpc) to its angular size (in radians)</td>
   </tr>
+  <tr>
+    <td>angular_diameter_dist(cosmo,&nbsp;z<sub>1</sub>,&nbsp;z<sub>2</sub>)</td>
+    <td>Ratio of the proper transverse size (in Mpc) of an object at redshift z<sub>2</sub> to its 
+    angular size (in radians), as seen by an observer at z<sub>1</sub></td>
+  </tr>
   <tr>
     <td>comoving_radial_dist(cosmo,&nbsp;z)</td>
     <td>Comoving radial distance to redshift z, in Mpc</td>
@@ -107,6 +112,9 @@ FlatLCDM(0.69,0.7399122024007928,0.26,8.779759920715362e-5)
 
 julia> angular_diameter_dist(c, 1.2)
 1784.0089227105113 Mpc
+
+julia> angular_diameter_dist(c, 0.7, 1.2)
+606.6521737365097 Mpc
 ```
 
 For each function returning a unitful number, you can specify a different unit

src/Cosmology.jl

@@ -148,22 +148,37 @@ hubble_time(c::AbstractCosmology, z) = hubble_time0(c)/E(c,z)
 
 Z(c::AbstractCosmology, z::Real; kws...) =
     QuadGK.quadgk(a->1/a2E(c,a), scale_factor(z), 1; kws...)[1]
+Z(c::AbstractCosmology, z₁::Real, z₂::Real; kws...) =
+    QuadGK.quadgk(a->1/a2E(c,a), scale_factor(z₂), scale_factor(z₁); kws...)[1]
 
 comoving_radial_dist(c::AbstractCosmology, z; kws...) = hubble_dist0(c)*Z(c, z; kws...)
+comoving_radial_dist(c::AbstractCosmology, z₁, z₂; kws...) = hubble_dist0(c)*Z(c, z₁, z₂; kws...)
 
 comoving_transverse_dist(c::AbstractFlatCosmology, z; kws...) =
     comoving_radial_dist(c, z; kws...)
+comoving_transverse_dist(c::AbstractFlatCosmology, z₁, z₂; kws...) =
+    comoving_radial_dist(c, z₁, z₂; kws...)
 function comoving_transverse_dist(c::AbstractOpenCosmology, z; kws...)
     sqrtok = sqrt(c.Ω_k)
-    hubble_dist0(c)*sinh(sqrtok*Z(c,z; kws...))/sqrtok
+    hubble_dist0(c)*sinh(sqrtok*Z(c, z; kws...))/sqrtok
+end
+function comoving_transverse_dist(c::AbstractOpenCosmology, z₁, z₂; kws...)
+    sqrtok = sqrt(c.Ω_k)
+    hubble_dist0(c)*sinh(sqrtok*Z(c, z₁, z₂; kws...))/sqrtok
 end
 function comoving_transverse_dist(c::AbstractClosedCosmology, z; kws...)
     sqrtok = sqrt(abs(c.Ω_k))
     hubble_dist0(c)*sin(sqrtok*Z(c,z; kws...))/sqrtok
 end
+function comoving_transverse_dist(c::AbstractClosedCosmology, z₁, z₂; kws...)
+    sqrtok = sqrt(abs(c.Ω_k))
+    hubble_dist0(c)*sin(sqrtok*Z(c, z₁, z₂; kws...))/sqrtok
+end
 
 angular_diameter_dist(c::AbstractCosmology, z; kws...) =
     comoving_transverse_dist(c, z; kws...)/(1 + z)
+angular_diameter_dist(c::AbstractCosmology, z₁, z₂; kws...) =
+    comoving_transverse_dist(c, z₁, z₂; kws...)/(1 + z₂)
 
 luminosity_dist(c::AbstractCosmology, z; kws...) =
     comoving_transverse_dist(c, z; kws...)*(1 + z)

test/runtests.jl

@@ -12,6 +12,7 @@ integrand(c, z) = 4pi*ustrip(comoving_volume_element(c, z))
 @testset "FlatLCDM" begin
     c = cosmology(h=0.7, OmegaM=0.3, OmegaR=0)
     @test angular_diameter_dist(c,1,rtol=dist_rtol) ≈ 1651.9145u"Mpc" rtol = dist_rtol
+    @test angular_diameter_dist(c,1,2,rtol=dist_rtol) ≈ 625.3444u"Mpc" rtol = dist_rtol
     @test comoving_radial_dist(c,1,rtol=dist_rtol) ≈ 3303.829u"Mpc" rtol = dist_rtol
     @test comoving_volume(c,1,rtol=dist_rtol) ≈ 151.0571u"Gpc^3" rtol = dist_rtol
     @test quadgk(z -> integrand(c, z), 0, 2.5)[1] ≈ ustrip(comoving_volume(c, 2.5))
@@ -26,6 +27,7 @@ end
 @testset "OpenLCDM" begin
     c = cosmology(h=0.7, OmegaK=0.1, OmegaM=0.3, OmegaR=0)
     @test angular_diameter_dist(c,1,rtol=dist_rtol) ≈ 1619.9588u"Mpc" rtol = dist_rtol
+    @test angular_diameter_dist(c,1,2,rtol=dist_rtol) ≈ 598.9118u"Mpc" rtol = dist_rtol
     @test comoving_radial_dist(c,1,rtol=dist_rtol) ≈ 3209.784u"Mpc" rtol = dist_rtol
     @test comoving_volume(c,1,rtol=dist_rtol) ≈ 140.0856u"Gpc^3" rtol = dist_rtol
     @test quadgk(z -> integrand(c, z), 0, 2.5)[1] ≈ ustrip(comoving_volume(c, 2.5))
@@ -40,6 +42,7 @@ end
 @testset "ClosedLCDM" begin
     c = cosmology(h=0.7, OmegaK=-0.1, OmegaM=0.3, OmegaR=0)
     @test angular_diameter_dist(c,1,rtol=dist_rtol) ≈ 1686.5272u"Mpc" rtol = dist_rtol
+    @test angular_diameter_dist(c,1,2,rtol=dist_rtol) ≈ 655.6019u"Mpc" rtol = dist_rtol
     @test comoving_radial_dist(c,1,rtol=dist_rtol) ≈ 3408.937u"Mpc" rtol = dist_rtol
     @test comoving_volume(c,1,rtol=dist_rtol) ≈ 163.8479u"Gpc^3" rtol = dist_rtol
     @test quadgk(z -> integrand(c, z), 0, 2.5)[1] ≈ ustrip(comoving_volume(c, 2.5))
@@ -54,6 +57,7 @@ end
 @testset "FlatWCDM" begin
     c = cosmology(h=0.7, OmegaM=0.3, OmegaR=0, w0=-0.9, wa=0.1)
     @test angular_diameter_dist(c,1,rtol=dist_rtol) ≈ 1612.0585u"Mpc" rtol = dist_rtol
+    @test angular_diameter_dist(c,1,2,rtol=dist_rtol) ≈ 607.6802u"Mpc" rtol = dist_rtol
     @test comoving_radial_dist(c,1,rtol=dist_rtol) ≈ 3224.1169u"Mpc" rtol = dist_rtol
     @test comoving_volume(c,1,rtol=dist_rtol) ≈ 140.3851u"Gpc^3" rtol = dist_rtol
     @test quadgk(z -> integrand(c, z), 0, 2.5)[1] ≈ ustrip(comoving_volume(c, 2.5))
@@ -68,6 +72,7 @@ end
 @testset "OpenWCDM" begin
     c = cosmology(h=0.7, OmegaK=0.1, OmegaM=0.3, OmegaR=0, w0=-0.9, wa=0.1)
     @test angular_diameter_dist(c,1,rtol=dist_rtol) ≈ 1588.0181u"Mpc" rtol = dist_rtol
+    @test angular_diameter_dist(c,1,2,rtol=dist_rtol) ≈ 585.4929u"Mpc" rtol = dist_rtol
     @test comoving_radial_dist(c,rtol=dist_rtol,1) ≈ 3147.6227u"Mpc" rtol = dist_rtol
     @test comoving_volume(c,1,rtol=dist_rtol) ≈ 132.0466u"Gpc^3" rtol = dist_rtol
     @test quadgk(z -> integrand(c, z), 0, 2.5)[1] ≈ ustrip(comoving_volume(c, 2.5))
@@ -82,6 +87,7 @@ end
 @testset "ClosedWCDM" begin
     c = cosmology(h=0.7, OmegaK=-0.1, OmegaM=0.3, OmegaR=0, w0=-0.9, wa=0.1)
     @test angular_diameter_dist(c,1,rtol=dist_rtol) ≈ 1637.5993u"Mpc" rtol = dist_rtol
+    @test angular_diameter_dist(c,1,2,rtol=dist_rtol) ≈ 632.5829u"Mpc" rtol = dist_rtol
     @test comoving_radial_dist(c,1,rtol=dist_rtol) ≈ 3307.9932u"Mpc" rtol = dist_rtol
     @test comoving_volume(c,1,rtol=dist_rtol) ≈ 149.8301u"Gpc^3" rtol = dist_rtol
     @test quadgk(z -> integrand(c, z), 0, 2.5)[1] ≈ ustrip(comoving_volume(c, 2.5))
@@ -97,10 +103,12 @@ end
     # Test that FlatLCDM works with non-Float64 (BigFloat in this example)
     c = cosmology(h=0.7, OmegaM=big(0.3), OmegaR=0)
     @test angular_diameter_dist(c,1,rtol=dist_rtol) ≈ 1651.9145u"Mpc" rtol = dist_rtol
+    @test angular_diameter_dist(c,1,2,rtol=dist_rtol) ≈ 625.3444u"Mpc" rtol = dist_rtol
     @test comoving_volume_element(c, big(1.41)) ≈ 3.4030879e10u"Mpc^3" rtol = dist_rtol
     # Test that FlatWCDM works with non-Float64 (BigFloat in this example)
     c = cosmology(h=big(0.7), OmegaM=0.3, OmegaR=0, w0=-0.9, wa=0.1)
     @test angular_diameter_dist(c,1,rtol=dist_rtol) ≈ 1612.0585u"Mpc" rtol = dist_rtol
+    @test angular_diameter_dist(c,1,2,rtol=dist_rtol) ≈ 607.6802u"Mpc" rtol = dist_rtol
     @test comoving_volume_element(c, big(1.41)) ≈ 3.1378625e10u"Mpc^3" rtol = dist_rtol
 end