*** Announcements ***           Date: 10-18-2000
+ office hours by appt.:
  call 303 Upson 255-0982, M-F 9:30-4:30
+ Ex7 due 10/26 -- it is easy, just CW
+ Read about I/O Functions in chapter 8.

*** Outline ***
+ Project 4 Intro
  - FIND
  - ISMEMBER
  - Random Numbers
  - String -->  Cell Array  --> Structure Array
  - CELL2STRUCT

*** Project 4 Intro ***
+ very useful function FIND(array)
  "find indices of nonzero elements"
  Ex: >>R=double('abcdef');       % R=97:102 
      >>find( R>=double('c') )
      ans =            

+ 5.1 hammingdistance.m
  go through string and keep track of how many chars don't match
  very useful (arr1==arr2)
  Ex: >>arr1=[1 3 4 2 3 5];
      >>arr2=[1 4 3 2 3 5];
      >>(arr1==arr2)
        ans =  

      >>                           % check whether ALL values match
        ans = 0

      >>                           % determine the number of mismatches nnz(arr1~=arr2)
        ans = 2

+ very useful function ISMEMBER(vector, array)
  "returns a vector containing 1 when the element of vector is in the
   set S and 0 otherwise"
  Ex: >>arr=[1 3 4 ;2 3 5];
      >>ismember(5,arr)
        ans = 1
      >>ismember([3 6 2],arr)
        ans = [1 0 1]

      >>arr='acgt'; 
      >>str='acacgbttfad';
      >>                           % find indices in str for characters other than in arr
        ans =       

+ 5.2 weighteddistance.m
  you know LOAD and SAVE, right?

+ Random numbers
  >>rand(1)   % or rand returns a double between 0 and 1 --> (0,1)
  Ex: % Generate a random number between 0 and 9 
      >>rand*10;                    % create a double random number between 0 and 10   
      >>floor(rand*10);             % create an integer random number between 0 and 9

      % Hint: Think about how many possible integer numbers you want to allow (here 10)
      >>                            % create an integer random number between 1 and 6           

+ String --> Cell Array 
  >>str1='acac'; str2='tggtgtg';
  >>C(1,1)={str1}; C(1,2)={str2};
  
  CELLSTR only works with array of strings where row must have same lengths!

+ Cell Array  --> Structure Array
  CELL2STRUCT(C,Field,Dim) :convert cell array to structure array
              C:     Cell array to be converted
              Field: Cell array or Character array with fieldnames 
              Dim:   =1 if each row of C turns into a field
                     =2 if each col of C turns into a field

  >>C(1,1)={str1}; C(1,2)={str2};
  >>F={'s4' 's7'}
  >>
    str =
         s4: 'acac'
         s7: 'tggtgtg'      
  
  >>C(1,1)={str1}; C(2,1)={str2};
  >>F={'s4' 's7'};
  >>
    str =
         s4: 'acac'
         s7: 'tggtgtg'