software

I have created and X Y Scatter chart and placed an Exponential Trend Line on
it with a good R2 result. I have added the equation to be shown on the chart.

How can I put the Constant values of this equation into separate cells
within the worksheet.

i.e. equation is Y = bE (cX)

I want to put the value of quot;bquot; and quot;cquot; into separate cells. Can anyone help?
--
Ken
--
Ken

Ken wrote:
gt; I have created and X Y Scatter chart and placed an Exponential Trend Line on
gt; it with a good R2 result. I have added the equation to be shown on the chart.
gt;
gt; How can I put the Constant values of this equation into separate cells
gt; within the worksheet.
gt;
gt; i.e. equation is Y = bE (cX)
gt;
gt; I want to put the value of quot;bquot; and quot;cquot; into separate cells. Can anyone help?
------------------

I don't believe you can capture the constants simply from the graph. However,
ask the Excel help system about the LOGEST( ) function which will provide them.

Bill

Hi,

Assuming that your x-values are in A2:A21 and y-values are in B2:B21, use
the following formulas to calculate b and c.

For b, =EXP(INTERCEPT(LN(B2:B21),A2:A21))
For c, =SLOPE(LN(B2:B21),(A2:A21))

Regards,
B. R. Ramachandranquot;Kenquot; wrote:

gt; I have created and X Y Scatter chart and placed an Exponential Trend Line on
gt; it with a good R2 result. I have added the equation to be shown on the chart.
gt;
gt; How can I put the Constant values of this equation into separate cells
gt; within the worksheet.
gt;
gt; i.e. equation is Y = bE (cX)
gt;
gt; I want to put the value of quot;bquot; and quot;cquot; into separate cells. Can anyone help?
gt; --
gt; Ken
gt; --
gt; Ken

David Braden has posted code to extract coefficients from the chart
trendline equation

groups.google.com/group/micro...440d271303e0d6

You must format the equation to display full precision (scientific w/ 14
decimal places) or you will lose accuracy.

Jerry

Ken wrote:

gt; I have created and X Y Scatter chart and placed an Exponential Trend Line on
gt; it with a good R2 result. I have added the equation to be shown on the chart.
gt;
gt; How can I put the Constant values of this equation into separate cells
gt; within the worksheet.
gt;
gt; i.e. equation is Y = bE (cX)
gt;
gt; I want to put the value of quot;bquot; and quot;cquot; into separate cells. Can anyone help?Many thanks B. R.Ramachandran, this worked fantastically!!!! KEN
--
Kenquot;B. R.Ramachandranquot; wrote:

gt; Hi,
gt;
gt; Assuming that your x-values are in A2:A21 and y-values are in B2:B21, use
gt; the following formulas to calculate b and c.
gt;
gt; For b, =EXP(INTERCEPT(LN(B2:B21),A2:A21))
gt; For c, =SLOPE(LN(B2:B21),(A2:A21))
gt;
gt; Regards,
gt; B. R. Ramachandran
gt;
gt;
gt; quot;Kenquot; wrote:
gt;
gt; gt; I have created and X Y Scatter chart and placed an Exponential Trend Line on
gt; gt; it with a good R2 result. I have added the equation to be shown on the chart.
gt; gt;
gt; gt; How can I put the Constant values of this equation into separate cells
gt; gt; within the worksheet.
gt; gt;
gt; gt; i.e. equation is Y = bE (cX)
gt; gt;
gt; gt; I want to put the value of quot;bquot; and quot;cquot; into separate cells. Can anyone help?
gt; gt; --
gt; gt; Ken
gt; gt; --
gt; gt; Ken

B.R. Ramachandran

Thanks for your help on this one. Also I need to get a Polynomial constants
for a 2 degree equation. Can you help? e.g. Z = aX(2) bX c.
I need a, b and c

--
Kenquot;B. R.Ramachandranquot; wrote:

gt; Hi,
gt;
gt; Assuming that your x-values are in A2:A21 and y-values are in B2:B21, use
gt; the following formulas to calculate b and c.
gt;
gt; For b, =EXP(INTERCEPT(LN(B2:B21),A2:A21))
gt; For c, =SLOPE(LN(B2:B21),(A2:A21))
gt;
gt; Regards,
gt; B. R. Ramachandran
gt;
gt;
gt; quot;Kenquot; wrote:
gt;
gt; gt; I have created and X Y Scatter chart and placed an Exponential Trend Line on
gt; gt; it with a good R2 result. I have added the equation to be shown on the chart.
gt; gt;
gt; gt; How can I put the Constant values of this equation into separate cells
gt; gt; within the worksheet.
gt; gt;
gt; gt; i.e. equation is Y = bE (cX)
gt; gt;
gt; gt; I want to put the value of quot;bquot; and quot;cquot; into separate cells. Can anyone help?
gt; gt; --
gt; gt; Ken
gt; gt; --
gt; gt; Ken