Baum_Welch_algorithm : negterm3: no visible global function definition
  for ‘dpois’
Baum_Welch_algorithm : negterm3: no visible global function definition
  for ‘dnorm’
Baum_Welch_algorithm: no visible global function definition for ‘dpois’
Baum_Welch_algorithm: no visible global function definition for ‘dgeom’
Baum_Welch_algorithm: no visible global function definition for ‘dnorm’
Baum_Welch_algorithm: no visible global function definition for ‘nlm’
HMM_simulation: no visible global function definition for ‘rpois’
HMM_simulation: no visible global function definition for ‘rnorm’
HMM_simulation: no visible global function definition for ‘rgeom’
HMM_simulation: no visible global function definition for ‘par’
HMM_simulation: no visible global function definition for ‘plot’
HMM_simulation: no visible global function definition for ‘abline’
HMM_simulation: no visible global function definition for ‘lines’
HMM_training: no visible global function definition for ‘sd’
Viterbi_algorithm : function_discr_log_L_p_norm: no visible global
  function definition for ‘pnorm’
Viterbi_algorithm: no visible binding for global variable ‘dpois’
Viterbi_algorithm: no visible binding for global variable ‘dgeom’
Viterbi_algorithm: no visible binding for global variable ‘dnorm’
cut_off_point_method: no visible global function definition for ‘par’
cut_off_point_method: no visible global function definition for ‘plot’
cut_off_point_method: no visible global function definition for
  ‘abline’
cut_off_point_method: no visible global function definition for
  ‘points’
cut_off_point_method: no visible global function definition for
  ‘barplot’
cut_off_point_method: no visible global function definition for
  ‘legend’
direct_numerical_maximization: no visible global function definition
  for ‘nlm’
forward_backward_algorithm : function_discr_log_L_p_norm: no visible
  global function definition for ‘pnorm’
forward_backward_algorithm: no visible binding for global variable
  ‘dpois’
forward_backward_algorithm: no visible binding for global variable
  ‘dgeom’
forward_backward_algorithm: no visible binding for global variable
  ‘dnorm’
forward_backward_algorithm: no visible global function definition for
  ‘dpois’
initial_parameter_training: no visible global function definition for
  ‘quantile’
initial_parameter_training: no visible global function definition for
  ‘sd’
rgenpois: no visible global function definition for ‘runif’
Undefined global functions or variables:
  abline barplot dgeom dnorm dpois legend lines nlm par plot pnorm
  points quantile rgeom rnorm rpois runif sd
Consider adding
  importFrom("graphics", "abline", "barplot", "legend", "lines", "par",
             "plot", "points")
  importFrom("stats", "dgeom", "dnorm", "dpois", "nlm", "pnorm",
             "quantile", "rgeom", "rnorm", "rpois", "runif", "sd")
to your NAMESPACE file.