I am so embarresed I cannot figure this out myself... but shoot, my lame brain is stumped!

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I have a worksheet that has a set of numbers n. In one column (A) I
have the original numbers n, in the second column (B) I have the
average of the last 10. I have both columns graphed on a single graph
so in effect I have the original data and a 10 period moving avergae.

I need to figure out the slope, as represented in degrees of angle of
this moving avergae between each of the two data points. ie, I'll have
a third column on the worksheet that in cell c12 says in effect:
"between points b11 and b12, the angle of the 10 period moving average
is 28 degrees...." etc.

So....

I looked up on google the equation to figure out slope:

slope = ((y2 - y1) / (x2-x1)) which makes sense. Here according to the
webpage I found on this Point A (or say the data in cell b11 on my
spreadsheet) has the coordinates x1,y1 and point B (or the data in
cell B12) has the coordinates x2,y2. Obvioslut just plug this in and
get slope right? Here is where my brain is like old cereal that has
been in the bowl too long... how can I get two numbers out of my
single number in cell b11? In other words if b11 says 42, where is the
2nd numner for the x,y coordinate thing so I can plug it into the
slope equation? I hoep I have articulated this in a comprehensible
way.

And that brings me to my 2nd question. The web page that describes how
to calculate slope:
http://cstl.syr.edu/fipse/GraphA/Unit4/Unit4Ex1.html

shows sample answers being 1/5 or 2. How does one then translate this
into degrees (aka, a 70 degree angle or 90 degree angle)?

Thanks for the remedial 4th grade math to any who can help me!
 
This is just a hunch or suggestion.
For (Y2-Y1) use the current value minus the previous value.
For (X2-X1) use the previous value.

Thus, when the consecutive values are the same, the slope = 0 which is
correct.
For any change, the slope will be (positive or negative) the percent change.

The reason the traditional formula is confusing is that you are measuring Y
using one set of values but X is not in the same units of measure as Y.

Hope this helps
 
<< I looked up on google the equation to figure out slope:

slope = ((y2 - y1) / (x2-x1)) which makes sense. Here according to the
webpage I found on this Point A (or say the data in cell b11 on my
spreadsheet) has the coordinates x1,y1 and point B (or the data in
cell B12) has the coordinates x2,y2. Obvioslut just plug this in and
get slope right? Here is where my brain is like old cereal that has
been in the bowl too long...

how can I get two numbers out of my single number in cell b11? In othe
words if b11 says 42, where is the 2nd numner for the x,y coordinat
thing so I can plug it into the slope equation? I hoep I hav
articulated this in a comprehensible
way. >>


I will make a few assumptions in solving your problem. First of all,
want to assume, e.g., that the numbers (coordinates) in a cell i
formatted this way *x,y*.

Being so, let us then assume that the entry in B11 is (4,2) and th
other point is in say, cell B12 and the coordinates are (5,3).

To determine the *x-coordinate* in cell B11, you can enter this formul
in, say. cell C11

=left(B11,find(",",B11)-1)

To determine the *y-coordinate* in cell B11, you can enter this formul
in, say. cell D11

=right(B11,len(B11)-search(",",B11))

The (x,y) coordinates in Cell B12 can be determined by simply replacin
"B11" in the above formula with "B12" and you can place "X" in Cell C1
and "Y" in Cell D12.

Hopefully, the above formulas answer your first question as how t
determine the x and y values of a cell entry.

Now, let's go to your second question ...


<< And that brings me to my 2nd question. The web page that describe
how
to calculate slope:
http://cstl.syr.edu/fipse/GraphA/Unit4/Unit4Ex1.html

shows sample answers being 1/5 or 2. How does one then translate this
into degrees (aka, a 70 degree angle or 90 degree angle)?

Thanks for the remedial 4th grade math to any who can help me!>>

Your slope can now be determined by the formula:

=(D12-D11)/(C12-C11)

Remember that

slope = tangent of the angle

hence the

angle of the slope = atan(slope)*180/pi() OR

=atan((D12-D11)/(C12-C11))*180/pi()

and the formula will give you the angle in degrees.

For this example (with the assumed coordinates of B11 and B12), yo
should come with a slope of 45 degrees.

Hope this will be of help to your problem
 
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