** issue

issue in age_weight_service.rb

  def gap_weight_for( age )
    difference = (value_of(age) - patient_age).abs
    puts difference.inspect
    x = difference * 0.1
    puts x.to_s
    x ** 1.07
  end

output

#<BigDecimal:88e1ae0,'0.16E2',9(27)>
1.6
#<BigDecimal:89368b0,'0.21E2',9(27)>
2.1
#<BigDecimal:8986900,'0.17E2',9(27)>
1.7
#<BigDecimal:89f7308,'0.13E2',9(27)>
1.3
#<BigDecimal:6eb8560,'0.8E1',9(27)>
0.8
#<BigDecimal:6f42d50,'0.17E2',9(27)>
1.7
#<BigDecimal:70002b0,'0.4E1',9(27)>
0.4
#<BigDecimal:8c1c1b0,'0.16E2',9(27)>
1.6
#<BigDecimal:8c869e8,'0.21E2',9(27)>
2.1
/projects/physioage/reporting/lib/age_weight_service.rb:43:in `**': #<Class:0x00000008c86380> can't be coerced into BigDecimal (TypeError)
        from /projects/physioage/reporting/lib/age_weight_service.rb:43:in `gap_weight_for'
        from /projects/physioage/reporting/lib/age_weight_service.rb:56:in `block (2 levels) in calculate_weights'
        from /projects/physioage/reporting/lib/age_weight_service.rb:52:in `each'
        from /projects/physioage/reporting/lib/age_weight_service.rb:52:in `block in calculate_weights'
        from /projects/physioage/reporting/lib/age_weight_service.rb:51:in `tap'
        from /projects/physioage/reporting/lib/age_weight_service.rb:51:in `calculate_weights'
        from /projects/physioage/reporting/lib/age_weight_service.rb:47:in `weights'
        from /projects/physioage/reporting/lib/age_weight_service.rb:96:in `fire'
        from /projects/physioage/reporting/lib/loaders/dataset_loader.rb:171:in `populate_age_weights'
        from /projects/physioage/reporting/lib/loaders/dataset_loader.rb:15:in `block in for'
        from /projects/physioage/reporting/lib/loaders/dataset_loader.rb:10:in `tap'
        from /projects/physioage/reporting/lib/loaders/dataset_loader.rb:10:in `for'
        from /projects/physioage/reporting/lib/loaders/dataset_loader.rb:135:in `block in populate_history'
        from /projects/physioage/reporting/lib/loaders/dataset_loader.rb:133:in `each'
        from /projects/physioage/reporting/lib/loaders/dataset_loader.rb:133:in `populate_history'
        from /projects/physioage/reporting/lib/loaders/dataset_loader.rb:17:in `block in for'
        from /projects/physioage/reporting/lib/loaders/dataset_loader.rb:10:in `tap'
        from /projects/physioage/reporting/lib/loaders/dataset_loader.rb:10:in `for'
        from /projects/physioage/reporting/app/models/visit.rb:91:in `data'
        from script/exports/change_in_physiological_age_export.rb:40:in `block (3 levels) in write'
        from script/exports/change_in_physiological_age_export.rb:38:in `map'
        from script/exports/change_in_physiological_age_export.rb:38:in `block (2 levels) in write'
        from script/exports/change_in_physiological_age_export.rb:11:in `block (2 levels) in each_patient'
        from /home/jw/.rvm/gems/ruby-1.9.3-p484/gems/activerecord-3.1.12/lib/active_record/relation.rb:15:in `each'
        from /home/jw/.rvm/gems/ruby-1.9.3-p484/gems/activerecord-3.1.12/lib/active_record/relation.rb:15:in `each'
        from script/exports/change_in_physiological_age_export.rb:10:in `block in each_patient'
        from /home/jw/.rvm/gems/ruby-1.9.3-p484/gems/activerecord-3.1.12/lib/active_record/relation.rb:15:in `each'
        from /home/jw/.rvm/gems/ruby-1.9.3-p484/gems/activerecord-3.1.12/lib/active_record/relation.rb:15:in `each'
        from script/exports/change_in_physiological_age_export.rb:9:in `each_patient'
        from script/exports/change_in_physiological_age_export.rb:24:in `block in write'
        from /home/jw/.rvm/rubies/ruby-1.9.3-p484/lib/ruby/1.9.1/csv.rb:1243:in `generate'
        from script/exports/change_in_physiological_age_export.rb:20:in `write'
        from script/exports/change_in_physiological_age_export.rb:51:in `<top (required)>'
        from /home/jw/.rvm/gems/ruby-1.9.3-p484/gems/railties-3.1.12/lib/rails/commands/runner.rb:47:in `eval'
        from /home/jw/.rvm/gems/ruby-1.9.3-p484/gems/railties-3.1.12/lib/rails/commands/runner.rb:47:in `<top (required)>'
        from /home/jw/.rvm/gems/ruby-1.9.3-p484/gems/railties-3.1.12/lib/rails/commands.rb:63:in `require'
        from /home/jw/.rvm/gems/ruby-1.9.3-p484/gems/railties-3.1.12/lib/rails/commands.rb:63:in `<top (required)>'
        from script/rails:6:in `require'
        from script/rails:6:in `<main>'