docstr: ...Test HawkesExpKern setting of step parameter
  of solver
docstr_tok: ["...","Test","HawkesExpKern","setting","of","step","parameter","of","solver"]
code: def test_HawkesExpKern_solver_step(self):
      """...Test HawkesExpKern setting of step parameter
      of solver
      """
      for solver in solvers:
          if solver in ["bfgs"]:
              msg = '^Solver "%s" has no settable step$' % solver
              with self.assertWarnsRegex(RuntimeWarning, msg):
                  learner = HawkesExpKern(
                      self.decays,
                      solver=solver,
                      step=1,
                      **Test.specific_solver_kwargs(solver),
                  )
                  self.assertIsNone(learner.step)
          else:
              learner = HawkesExpKern(
                  self.decays,
                  solver=solver,
                  step=self.float_1,
                  **Test.specific_solver_kwargs(solver),
              )
              self.assertEqual(learner.step, self.float_1)
              self.assertEqual(learner._solver_obj.step, self.float_1)
              learner.step = self.float_2
              self.assertEqual(learner.step, self.float_2)
              self.assertEqual(learner._solver_obj.step, self.float_2)
  
          if solver in ["sgd"]:
              msg = "^SGD step needs to be tuned manually$"
              with self.assertWarnsRegex(RuntimeWarning, msg):
                  learner = HawkesExpKern(
                      self.decays, solver="sgd", max_iter=1
                  )
                  learner.fit(self.events, 0.3)
  
imports: import unittest
  import numpy
  from tick.base.inference import InferenceTest
  from tick.hawkes import SimuHawkesExpKernels
  from tick.hawkes.inference import HawkesExpKern
  from tick.hawkes.model.model_hawkes_expkern_leastsq import ModelHawkesExpKernLeastSq
  from tick.hawkes.model.model_hawkes_expkern_loglik import ModelHawkesExpKernLogLik
  from tick.prox import ProxNuclear
  from tick.prox import ProxPositive, ProxL1, ProxL2Sq, ProxElasticNet
  from tick.solver import AGD, GD, BFGS, SGD, SVRG
label_desc: Use image node_id 13 for calling the Test obj's underlying member method code with example usage: obj.test_HawkesExpKern_solver_step() without return types