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TIME





                                            HH:MM:SS                            HH.MM.SS AM/PM
                                              13:45:22                             01.25.30 PM



                                          HH.MM AM/PM                                HH.MM
                                          (12 Hour clock)                        (24 Hour Clock)
                                             02.45 AM                                 16.30

                 •  String Data Type: A string is a sequence of characters that include:
                    o   alphabets A – Z and a – z.

                    o   numbers 0 – 9.
                    o   special characters including spaces, @, *, ?, etc.
                 All string data is enclosed within double quotes or single quotes. For examples:
                 “I hate exams”, ‘APPLE’, “Pin Code 876543”, ‘I stay at 23, Pocket Z, Chandni Chowk’.
                 •  Categorical Data: Categorical data is a data type with two or more categories. For example, a restaurant serving
                    pizzas may group your orders on the type of pizza you order—chicken, onion capsicum, pepperoni, etc. In this
                    case, the type of pizza ordered is the categorical data. Categorical data can also take numerical values such as 0
                    for women and 1 for men. However, these numbers do not have any mathematical meaning. These data are called
                    categorical because they can be grouped according to the variables present in the certificate, such as class, gender,
                    departments, schoolhouse, car type, etc. The easiest way to verify if the data is categorical or numeric is to compute
                    the average. If you can estimate the average, it will be considered a numerical value. If you cannot calculate the
                    average, it is considered categorical.

                        Representation of Data


                 Large volumes of data must be presented in a manner that enables the user to interpret the important aspects of the
                 data with minimum time and effort. The easiest way to do this is by using graphs. Let us learn about some the graphs
                 in detail.


                 Line Graph
                 A line graph or chart is a pictorial display of data that changes constantly over time. It is especially used to show trends
                 (upwards or downwards). Let us consider the following data:

                                                   Month      No. of cars sold in a year

                                                     Jan                 50
                                                     Feb                 30

                                                     Mar                 40
                                                     Apr                 35

                                                     May                 20
                                                     Jun                 15



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