UnknownApiError: Network error communicating with endpoint

[sumeetkhatri]

For the past week, I have been constantly getting the following error on the QVM:

`UnknownApiError Traceback (most recent call last)
in ()
----> 1 minSVD3_2_1,gates_minSVD3_2_1,CSVD3_2_1,GSVD3_2_1,time_totSVD3_2_1,nfevSVD3_2_1=QAQC_optimize_gates(U3_2,3,Alg3_2[0],gates3_2_1,1000,'quantum',display=True,collective=False,slowdown=False,arb_2qubit=False)

/home/sumeet/Documents/environment-matrix/optimize_1q_gates_env_mat.py in QAQC_optimize_gates(U, n, sequence, gates_init, max_sweeps, method, display, collective, slowdown, arb_2qubit)
285 #print sweep_order
286
--> 287 gates_check,count=QAQC_sweep_sequence(U,sequence,G[sweep_count-1],n,method,collective,slowdown,sub_sweep_order,arb_2qubit)
288
289 if method=='classical':

/home/sumeet/Documents/environment-matrix/environment_matrix.py in QAQC_sweep_sequence(U, sequence, gates, n, method, collective, slowdown, order, arb_2qubit)
162 E=E+10*gates_new[i]
163 else:
--> 164 E,count=QAQC_generate_env_matrix(U,sequence,gates_new,i,n,method,arb_2qubit)
165 if slowdown:
166 E=E+gates_new[i]

/home/sumeet/Documents/environment-matrix/environment_matrix.py in QAQC_generate_env_matrix(U, sequence, gates, gate, n, method, arb_2qubit)
45 qubits_discard=np.setdiff1d(indices,qubit)
46 if method=='quantum':
---> 47 return partialtrace_U(U_right.HUU_left.H,n,list(qubits_discard.astype(int)),20000)
48 elif method=='classical':
49 return np.matrix(TrX(U_right.HUU_left.H,list(qubits_discard.astype(int)),list(2*np.ones(n).astype(int)))),0

/home/sumeet/Documents/environment-matrix/unitary_trace.py in partialtrace_U(U, n, sys_discard, num_samples, display)
388 for x in bits:
389 #for alpha in bits:
--> 390 mat_elem_Re,mat_elem_Im=generate_matrix_element(x)
391 #print generate_matrix_element.counter
392 for alpha in bits:

/home/sumeet/Documents/environment-matrix/unitary_trace.py in generate_matrix_element(x)
364
365 results_Re=qvm.run(p_Re,[i for i in range(k+1)],num_samples)
--> 366 results_Im=qvm.run(p_Im,[i for i in range(k+1)],num_samples)
367
368 for (result_Re,result_Im) in zip(results_Re,results_Im):

/usr/local/lib/python2.7/dist-packages/pyquil/api/qvm.pyc in run(self, quil_program, classical_addresses, trials, needs_compilation, isa)
134 return job.result()
135 else:
--> 136 response = post_json(self.session, self.sync_endpoint + "/qvm", payload)
137 return response.json()
138

/usr/local/lib/python2.7/dist-packages/pyquil/api/_base_connection.pyc in post_json(session, url, json)
86 res = session.post(url, json=json)
87 if res.status_code >= 400:
---> 88 raise parse_error(res)
89 return res
90

/usr/local/lib/python2.7/dist-packages/pyquil/api/_base_connection.pyc in parse_error(res)
103
104 if 'error_type' not in body:
--> 105 raise UnknownApiError(str(body))
106
107 error_type = body['error_type']

UnknownApiError: {u'message': u'Network error communicating with endpoint'}

The server has failed to return a proper response. Please describe the problem
and copy the above message into a GitHub issue at:
https://github.com/rigetticomputing/pyquil/issues`

I have seen a similar post about this UnknownApiError, but not exactly this one.

[ryankarle]

Hi @sumeetkhatri, sorry for the late response- this was a recurring issue with our old stack. If you haven't already, please try downloading our Forest SDK here. Please note that we'll be likely updating the package later this week!