# PLF – Program Design Assignment

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In CLIO, if you enter search terms without an operator, AND will automatically be inserted between them (but make sure that Javascript is enabled on your computer, or the search will fail). OR The operator OR broadens the search to include records containing either keyword, or both. The OR search is particularly useful when there are several common synonyms for a concept, or variant spellings of a word. Examples: adolescent or teen? Divided or “middle ages” Virgil or Virgil NOT Combining search terms with the NOT operator narrows the search by excluding unwanted terms. These Venn diagrams help to visualize the meaning of AND, OR and NOT; the colored area indicates the items that will be retrieved in each case. AND moths AND butterflies You want to find books that are about both moths AND butterflies OR moths OR butterflies You want to find books that are about moths, books that are about butterflies, and books that discuss both: OR means MORE. Tots NOT butterflies You want to find books that are about moths, but EXCLUDE those that discuss butterflies Variable Types Following table gives you details about standard integer types with its storage sizes ND value ranges: Type Storage size Value range String 1 byte Letters and other special characters 2 or 4 bytes -32,768 to 32,767 or to short 2 bytes -32,768 to 32,767 long 4 bytes to Floating-Point Types Following table gives you details about standard floating-point types with storage sizes and value ranges and their precision: Type Precision float 4 byte 1. E-38 to 3. E+38 6 decimal places double 8 byte 2. 3+308 to 1. E+308 15 decimal places long double 10 byte 3. 4+4932 to 1. 1 E+4932 19 decimal places Variables A variable is a symbolic name for (or reference to) information. The variable’s impressments what information the variable contains. They are called variables because the represented information can change but the operations on the variable remain the same. In general, a program should be written with “Symbolic” notation, such that a statement slipways true symbolically.

For example if I want to know the average of two grades, We can write “average = (grade_l + grade_2) / 2. 0;” and the variable average will then contain the average grade regardless of the scores stored in the variables, grade_l and grade_2. There are only a few things you can do with a variable: . Create one (with a nice name). A variable should be named to represent all possible values that it might contain. Some examples are: midterm_score, midterm_scores, data_points, course_name, etc. 2.