compute_design_performance: no visible global function definition for
  'read.csv'
compute_design_performance : get_power: no visible global function
  definition for 'rnorm'
compute_design_performance : power_curve_plot: no visible global
  function definition for 'plot'
compute_design_performance : power_curve_plot: no visible global
  function definition for 'lines'
compute_design_performance : power_curve_plot: no visible global
  function definition for 'legend'
compute_design_performance : expected_sample_size_plot: no visible
  global function definition for 'plot'
compute_design_performance : expected_sample_size_plot: no visible
  global function definition for 'lines'
compute_design_performance : expected_sample_size_plot: no visible
  global function definition for 'legend'
compute_design_performance : expected_duration_plot: no visible global
  function definition for 'plot'
compute_design_performance : expected_duration_plot: no visible global
  function definition for 'lines'
compute_design_performance : expected_duration_plot: no visible global
  function definition for 'legend'
compute_design_performance : boundary_adapt_plot: no visible global
  function definition for 'matplot'
compute_design_performance : boundary_adapt_plot: no visible global
  function definition for 'legend'
compute_design_performance : boundary_standard_H0C_plot: no visible
  global function definition for 'matplot'
compute_design_performance : boundary_standard_H0C_plot: no visible
  global function definition for 'legend'
compute_design_performance : boundary_standard_H01_plot: no visible
  global function definition for 'matplot'
compute_design_performance : boundary_standard_H01_plot: no visible
  global function definition for 'legend'
Undefined global functions or variables:
  legend lines matplot plot read.csv rnorm
Consider adding
  importFrom("graphics", "legend", "lines", "matplot", "plot")
  importFrom("stats", "rnorm")
  importFrom("utils", "read.csv")
to your NAMESPACE file.