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Names tutorial M: Fine print |
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There are many small details that we left out of this tutorial, in order to avoid distracting from the main purpose, which is to explain how to use Excel's naming features as concisely as possible. Here are some of those details. LESSON A: GOTO and Lesson B: Defining names Goto (F5) is not the only way to Goto a particular cell and Insert | Name | Define is not the only way to define a name. Microsoft's literature illustrates another method, which is to use the area next to the formula bar. Microsoft calls this space the name box.
The Name box acts as a combination of the Goto and the Define names commands.
We find this last point in brackets very unattractive
There are several other reasons why we don't recommend using the name box.
We favor the Goto and Insert | Name | Define commands as they have been present in a consistent way in every version of Excel from the first, and don't suffer any of these unattractive qualities. In our example, the cells that we wanted to name happened to have labels nearby that said Sales and Costs. Excel offered them as suggested candidates for names when we used the the Insert Name Define Command. Where a label consists of more than one word, as in Capital expenditure, Excel would propose Capital_expenditure as the suggested name. The reason is that names can be made up of letters, digits, the underscore, and a full stop (period). Other characters are not allowed, so Excel replaces the space, which is not allowed, with an underscore, which looks similar and is allowed. Operis's own style is not to accept Excel's suggestions when they involve underscores. Underscores are hard to see next to the spreadsheet's grid lines, and can be mistaken for spaces or, less commonly, minus signs.
They also subconsciously disrupt the flow of the formula when reading it. =Capital_Expenditure+Income_Tax reads like Expenditure+Income embedded in the middle of some other material. Instead, Operis recommends using a mixture of upper and lower case letters to indicate the word boundaries, as in CapitalExpenditure-IncomeTax. Some people call this mixture of letters camel case, or bumpy case. The way name definitions are adjusted automatically when the cells they refer to change location is consistent with the way coordinate references in a formula are adjusted when the cells they refer to move. However, the effect of moving a formula expressed in names is frequently not the same as the effect of moving a formula expressed in coordinates.
The formula is unchanged, but its interpretation in a new location will be different due to column matching. Some see this difference in behaviour between formulas expressed in names and formulas expressed in coordinates as confusing. Others consider it valuable; formulas expressed in names will always refer consistently to columns, no matter how much mutilation they suffer with cutting and pasting. The Apply names command obeys the One Cell Rule. That's why we included the direction in Step 2 "Select the cell which calculates profit using coordinate references...". It's partly because that cells contains a formula, and we want to see how it is affected when we start using the Apply names command. But it's also so that the relevant cell will in fact be acted upon by the command. The Apply names command described in this lesson is built into Excel. OAK has a command, also called Apply Names, which looks almost identical and performs the same action, but is more convenient and more powerful. Lesson I: Row and Column Matching A non-obvious point is that row and column matching is connected with names only indirectly. Expressions such as =Costs are resolved to =D7:M7 (or whatever the name definition indicates). That formula cites several cells and will typically provoke column matching. The column matching would equally happen if the formula had been written in coordinate notation. To this extent, it is not a property of the names directly, but a fundamental mechanism of the way Excel interprets a formula that is indirectly activated when names are used. LESSON K: Controlling aggregation The Apply names command obeys the One Cell Rule. That's why we included the direction in Step 2 "Select any one cell." Opinion is divided on the technique taught here. Operis finds it valuable, uses it and teaches it. Others feel that it demands a finely detailed knowledge of how Excel works that is not universal, and therefore not suitable for use in spreadsheets that are to be widely accessible. Common ground can be found in the advice that wherever there is ambiguity, the clearest possible formulation should be used. |