Page 246 - Data Science class 11
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2.  Explain variable assignment in R.
          Ans.  There are three methods of variable assignment. The three ways are: leftward, rightward and equal to operators of R.
               Assignment using the equal to operator
               X=65

               Assignment using the leftward operator
               X←65
               Assignment using the rightward operator
               65→X
            3.  What are the four main categories of operators for vectors in R programming language?
          Ans.  The four main categories of operators in R are as follows:
              •  Arithmetic operators:
                  •  These operators are used to perform arithmetic operations on vectors. The operators are +, -, *, / ,%%, ^.

              •  Relational operators:
                  •   These operators compare elements of one vector with the corresponding elements of the second vector. The
                   relational operator are: >, < , >=, <=, ==, !=
              •  Logical operators:

                  •   These operators are applicable only to logical, numeric or complex type. The result of the comparison is a Boolean
                   value. The logical operators are: &, |, ! (all these three check individual elements of the vector) &&(only checks the
                   first element of both the vectors).



                                              Unsolved Exercise


             Objective Type Questions (Section A)


        A.  Tick ( ) the correct option.

            1.  How many types of R objects are present in the R data type?
              a.  4                                              b.  5
              c.  6                                              d.  7

            2.  The ______________________ in R is a vector.
              a.  Basic data structure                           b.  Basic datatypes
              c.  Both a and b                                   d.  None of these

            3.  Vectors come in two parts: ______________________ and ______________________.
              a.  Atomic vectors and matrix                      b.  Atomic vectors and array
              c.  Atomic vectors and list                        d.  None of these

            4.  ______________________ and ______________________ are types of matrices functions?
              a.  Apply and supply                               b.  Apply and lapply
              c.   Both a and b                                  d.  None of these
            5.  Which of the following finds the maximum value in the vector x, excluding missing values ______________________?

              a.  rm(x)                                          b.  all(x)
              c.  max(x, na.rm=TRUE)                             d.  x%in%y


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