search for: postp

Dear friends - this is a very simple question - I have a data frame 'data.frame': 87 obs. of 3 variables: $ ID : int 1 1 1 2 2 2 3 3 3 4 ... $ prep : num 1.18 1.38 1.34 1.93 2.38 2.24 1.17 1.13 1.21 1.89 ... $ postp: num 0.63 0.71 0.75 1.01 1.12 1.07 0.87 0.64 0.7 0.8 ... - 29 persons (ID) each measured three times before and after an intervention: prep and postp - I need data rearranged like ID time val 1 1 prep 1 2 postp 1 1 1 2 1 1 1 2 I cannot make reshape or stack do the...

...191/lib/ruby/1.9.1/mkmf.rb:529:in `try_func'' from C:/Ruby191/lib/ruby/1.9.1/mkmf.rb:774:in `block in have_func'' from C:/Ruby191/lib/ruby/1.9.1/mkmf.rb:670:in `block in checking_for'' from C:/Ruby191/lib/ruby/1.9.1/mkmf.rb:276:in `block (2 levels) in postp one'' from C:/Ruby191/lib/ruby/1.9.1/mkmf.rb:250:in `open'' from C:/Ruby191/lib/ruby/1.9.1/mkmf.rb:276:in `block in postpone'' from C:/Ruby191/lib/ruby/1.9.1/mkmf.rb:250:in `open'' from C:/Ruby191/lib/ruby/1.9.1/mkmf.rb:272:in `postpon...

Hey everybody, I''m trying to make an example of a small networking site, and when I log in a user, it should redirect and show his profile, but I get the following error: NoMethodError in User#index Showing app/views/user/index.html.erb where line #5 raised: undefined method `screen_name'' for nil:NilClass Extracted source (around line #5): 2: Your basic information 3: