From 54d50176217e785dd06fbfa904971b80982d0e4f Mon Sep 17 00:00:00 2001 From: Christophe Piveteau Date: Mon, 22 Jun 2020 20:28:25 +0200 Subject: [PATCH] fixed partial trace constraint in cvx fitting routine (#438) (cherry picked from commit 3b72172015f31c64f62779c4f6f5bf8602142c1f) --- qiskit/ignis/verification/tomography/fitters/cvx_fit.py | 1 + 1 file changed, 1 insertion(+) diff --git a/qiskit/ignis/verification/tomography/fitters/cvx_fit.py b/qiskit/ignis/verification/tomography/fitters/cvx_fit.py index 8017d6a51..7c2e9a9a5 100644 --- a/qiskit/ignis/verification/tomography/fitters/cvx_fit.py +++ b/qiskit/ignis/verification/tomography/fitters/cvx_fit.py @@ -155,6 +155,7 @@ def cvx_fit(data: np.array, sdim = int(np.sqrt(dim)) ptr = partial_trace_super(sdim, sdim) cons.append(ptr @ cvxpy.vec(rho_r) == np.identity(sdim).ravel()) + cons.append(ptr @ cvxpy.vec(rho_i) == np.zeros(sdim*sdim)) # Rescale input data and matrix by weights if they are provided if weights is not None: