Microsoft Office Tutorials and References
In Depth Information
Considering Form versus Function
If you used a formula , you might enter
=C5+C6+C7+C8+C9 in cell C10 to display the
total of those cells. Although entering this
formula is not particularly difficult, it is tedious.
Instead of typing such a formula, you can use
the SUM function to get the same results much
more quickly. As you can see in Figure 3-1, the
function =SUM(C5:C9) is entered into cell C10
to compute the total you need.
For example, there’s a PMT function you can use
to calculate monthly payments on a loan. You
feed the PMT function an interest rate, total
number of payments over the life of the loan, and
the loan amount, and presto! The PMT function
calculates the amount due each month.
And the fun doesn’t end there: using the PMT
function, you could compare the interest rates
on various loans of particular amounts, and
purchase prices of several homes in your area, and
quickly identify which home is the best deal for
you. If you had to work manually, computing
these same payment amounts would be difficult
and time-consuming, and by the time you figured
things out, somebody else might have already
bought the home of your dreams.
You learn to enter a function properly in the
next section, “Understanding Function Syntax.”
For now, let’s concentrate on the basics. Again, a
function is a pre-programmed formula. You feed
a function some data, such as a range of cells, and
it spits out an answer, such as the total of the
values in those cells. What kind of data, you ask?
Not to worry: when you enter a function, Excel
provides you with a wizard that assists you in
filling in the blanks so you won’t fail to provide
the function with some needed data.
Obviously, the SUM function is pretty simple,
and something you might be able to do without
in situations where you are adding the contents
of only three or four cells. But try adding up a
long column or a range of cells using a regular
formula, and you will soon tire of typing all those
plus signs between cell addresses. In addition to
the SUM function, Excel provides many other
functions, grouped into various categories such
as Financial, Lookup & Reference, and Math & Trig.