Auto Fit Selection automatically adjusts rows and columns to fit the data within them.
In the case of a row the cell with the tallest data sets the height for the row as whole. With a column the cell with the widest data sets the width for the column as a whole. Completely empty rows and columns retain the height/width they had before Auto Fit was applied.
Before applying Auto Fit, select the appropriate rows or columns: click on a column bar at the top to select a column, on the row bar at the left to select a row (you can drag your mouse to select several adjacent rows/columns, or hold down the Control key and click on the appropriate non-adjacent rows/columns one by one to select them).
Select Column or Row from the Format menu, and then select Auto Fit Selection.
The selected rows or columns will be adjusted immediately to fit the data they contain.
Note that you can select Width or Height instead of Auto Fit Selection if you would like to make your own column or row adjustments. You can return a column/row to its standard size by selecting Standard Width/Standard Height.
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