Ints vs. Floats Categorizing Grid Tammy VanDeGrift and Kate Deibel March 30, 2004 Categorizing Grid

This activity allows instructors to see if students are aware of when it is best to use an integer or a floating-point number.

This activity will give you the opportunity to decide what sort of variable you would use when programming. Place each item in the Values box under the variable type that would best represent it.



Integer Floating-Point






Values
  1. Current temperature in degrees Celsius
  2. The population of lemmings
  3. Your grade point average
  4. A person's age in years
  5. A person's weight in pounds
  6. A person's height in meters
  7. Miles travelled
  8. Number of rainy days in the past month
  9. A locker number
  10. Number of seconds remaining in a game
  11. The sum of a series of integers
  12. The average of a series of integers

The following are suggestions, but several of the items in this activity are meant to encourage discussion.

  1. FP: Current temperature in degrees Celsius
  2. INT: The population of lemmings
  3. FP: Your grade point average
  4. INT: A person's age in years
  5. INT: A person's weight in pounds
  6. FP: A person's height in meters
  7. INT: Miles travelled
  8. INT: Number of rainy days in the past month
  9. INT: A locker number
  10. FP: Number of seconds remaining in a basketball game
  11. INT: The sum of a series of integers
  12. FP: The average of a series of integers

Run through the grids and mark incorrect or missing entries. Identify the most common errors as well as any patterns that could explain student confusion. Reflect upon these errors and report them back to the class as you see fit.

For each item, have the students also give a proper, well-named variable declaration in addition to the categorizing grid. Have students work in groups to complete this activity. The instructor may want to circulate throughout the groups to ensure that each group is making progress. After the groups have completed their lists, the instructor can ask for votes on each item. It is important that the instructor explains why each data structure is appropriate for the task. Have students work individually on their lists and then form groups of 4-5 people to discuss their individual lists with other members of the group. Develop analytic skills Develop ability to draw reasonable inferences from observations Improve memory skills Develop appropriate study skills, strategies, and habits Learn terms and facts of this subject Learn concepts and theories of this subject Integers Floating point numbers Design Types Variables LOW LOW LOW LOW Lecture Next Day Summary Class Discussion Homework Has Been Enabled Classes Structs Design Functions