enter value for x in excel trendline equation

Reason: we took the log of a which results in ln(a). Reason: we took the log of x B which results in B*ln(X). Recall that our power model is in the form y=ax Bī =. With this form, it is now possible to fit the regression line with linear regression and use the equation for R Squared.įit a linear model to the new dataset. You might think that the ln(x) part would make linear regression inappropriate, however, linear regression means that it is linear in parameters. This model can now be fit with linear regression. The Power regression model is in the form. However, the power equation can be converted to linear. 6782.Īdditionally, Rsquared is only valid for linear regression Models. The correct equation for Rsq is Also, in the most current version of Excel, the Rsquared for your dataset is. SsReg += math.pow(((intercept * math.pow(xValue, slope)) -yMean), 2).toDouble() SumOfYSquare += math.pow(yValue, 2).toInt() SumOfXSquare += math.pow(xValue, 2).toInt() Int sumOfX = 0,sumOfY = 0,sumOfXY = 0, sumOfXSquare = 0, sumOfYSquare = 0 ĭouble slope = 0.5204, intercept = 2.3133 I have implemented the following code snippet logic to achieve the R squared value List xValue = Here ȳ is the mean value of y and ŷ is the regression equation, here ŷ forĮxponential is y = ae^xb and for power is y = ax^b StrEquation = s.Trendlines(1).DataLabel.Tried to calculate the R-squared value for the exponential and power trendline type using the following equation. In the loop you can check the value of the equation and exit when it's non-empty (of if some max time has passed so you don't end up stuck in the loop forever) ThemeColor = 5 'msoThemeColorAccent enumeration starts at 5 Try adding a loop with DoEvents to allow Excel to 'catch up' with your code. UpToX = Split(strEquation, 'x') 'upToX = 'y = m'ĪfterEquals = Split(upToX(0), ' ') 'afterEquals = 'm' StrEquation = s.Trendlines(1).DataLabel.Text 'strEquation = 'y = m*x + b'

'THIS WORKS WHEN STEPPING THROUGH, but NOT RUNNING?

S.Trendlines(1).DisplayEquation = True 'displays the equation for each new trendline S.Trendlines.Add 'adds a trendline to series (s) 'Debug.Print s.Name 'debug print which series 's' is being manipulated Here is my script that runs on an active chart: ThemeColor = 5 'msoThemeColorAccent enumeration starts at 5įor Each s In ActiveChart.SeriesCollection Subscript out of range on the line afterEquals = Split(upToX(0), ' '). This is a very repeatable error where I can step through all series and extract all equations, or step through the first trendline and then run the rest and the script will break on the second trendline with Run-time error 9. I can extract the trendline equations when stepping through the script using F8, but when I remove breakpoints and run with F5 s.Trendlines(1).DataLabel.Text only returns an empty string to strEquations. I am trying to build a collection of the slopes from each trendline in an active chart.

Enter value for x in excel trendline equation