Spreadsheets Relative & Absolute Addresses CIL 102 ‘08 Fall

Relative & Absolute Addresses The concept of relative and absolute addresses becomes relevant when a spreadsheet user builds spreadsheets and copies formulas Copying formulas is frequently performed as a part of fundamental process

Simple Relative Address Example Compute perimeter and area of rectangles Formulas – P = 2*(L+W) – A = L*W Use labels to set up your table

Simple Relative Address Example Compute perimeter and area of rectangles Place perimeter formula in the first row Place area formula in the first row

Simple Relative Address Example Compute perimeter and area of rectangles Highlight the two formulas and select Copy Copy them to the remaining slots in the two columns by highlighting the area and select Paste

Simple Relative Address Example Compute perimeter and area of rectangles As you move the cursor from formula to formula, not how the references to the length and width are adjusted, relative to the formula. The formulas in row 4 reference the length and width in row 4, the formulas in rows 5, reference the values in row 5, and so forth.

Simple Relative Address Example As long as the addresses associated to a formula change as the formula location changes, then relative addressing is fine RULE OF THUMB Normally, formula references within a table are relative addressed as long as data and formulas are in rows or columns. Use a color highlight for each table to guide you.

Simple Absolute Address Example To illustrate absolute addressing, consider this variation of the perimeter/area table where the length is fixed. Perimeter and area change with length.

Simple Absolute Address Example Note that the length is outside of the table, it stays fixed. The width varies from row to row.

Simple Absolute Address Example The F4 Key. When you point to the length, press the F4 key. Note the $ symbols – this indicates an absolute address The width is a relative address

Simple Absolute Address Example The F4 Key. When the formula is duplicated down the column, the length reference says fixed (absolute), the width reference is relative

Simple Absolute Address Example The F4 Key. Complete the area computation in the same manner

Simple Absolute Address Example The F4 Key. Complete the Area computation with one absolute and one relative address. Copy the formula Note the absolute and relative references.

GPA Calculator

List your courses List your grades List the number of credits

GPA Calculator Lookup the grade in the table and record the points Compute the total points Sum the points Sum the credits Compute the GPA

Look up the grade Vertical look up table The look up table is outside of the GPA table, hence ABS address. The grade being looked up is in the GPA table, hence REL address

Vlookup Lookup_value: The grade (relative address) Table_Array: The table (Absolute address) Col_index_num: Number in column 2

Vlookup Col_index_num: Number in column 2 Table_Array: The table (Absolute address) Lookup_value: The grade (relative address)

VLookup

Multiply points * credits

Copy formulas down columns

Auto Sum Credit column Total points column

GPA Divide total points by total credits