[test] imtime_bubble_chi0_wk static DLR implementation test

Author: HugoStrand

test/python/chi00_square_lattice_dlr.py

@@ -13,9 +13,12 @@
 from triqs_tprf.tight_binding import TBLattice
 from triqs_tprf.lattice import lattice_dyson_g0_wk
 from triqs.gf.meshes import MeshDLRImFreq
+
 from triqs_tprf.lattice import dlr_on_imfreq
 from triqs_tprf.lattice import lindhard_chi00
 
+from triqs_tprf.lattice_utils import imtime_bubble_chi0_wk
+
 # ----------------------------------------------------------------------
 
 
@@ -39,6 +42,7 @@ def test_square_lattice_chi00_dlr():
 
     n_k = (2, 2, 1)
     nw = 50
+    nw_f = 1024
     lamb = 10.
     eps = 1e-8
 
@@ -80,17 +84,37 @@ def test_square_lattice_chi00_dlr():
     kmesh = t_r.get_kmesh(n_k)
     e_k = t_r.fourier(kmesh)
 
+    wmesh = MeshImFreq(beta=beta, S='Fermion', n_max=nw_f)
+    DLRwmesh = MeshDLRImFreq(beta, 'Fermion', lamb, eps)
+    
     wmesh_bose = MeshImFreq(beta=beta, S='Boson', n_max=nw)
     DLRwmesh_bose = MeshDLRImFreq(beta, 'Boson', lamb, eps)
 
-    
     print('--> chi00_wk analytic')
     chi00_wk_analytic = lindhard_chi00(e_k=e_k, mesh=wmesh_bose, mu=mu)
     chi00_Dwk_analytic = lindhard_chi00(e_k=e_k, mesh=DLRwmesh_bose, mu=mu)
 
     print('--> compare')
     compare_g_Dwk_and_g_wk(chi00_Dwk_analytic, chi00_wk_analytic)
 
+    print('--> g0_wk')
+    g0_wk = lattice_dyson_g0_wk(mu=mu, e_k=e_k, mesh=wmesh)
+
+    print('--> g0_Dwk')
+    g0_Dwk = lattice_dyson_g0_wk(mu=mu, e_k=e_k, mesh=DLRwmesh)
+    
+    print('--> chi00_wk')
+    chi00_wk = imtime_bubble_chi0_wk(g0_wk, nw=1, verbose=False)
+
+    print('--> chi00_wk_DLR')
+    chi00_wk_DLR = imtime_bubble_chi0_wk(g0_Dwk, nw=1, verbose=False)
+    
+    diff = np.max(np.abs(chi00_wk.data - chi00_wk_DLR.data))
+    print(f'diff = {diff:2.2E}')
+    
+    np.testing.assert_array_almost_equal(chi00_wk.data, chi00_wk_DLR.data, decimal=4)
+    
+    
 # ----------------------------------------------------------------------
 if __name__ == '__main__':
     test_square_lattice_chi00_dlr()