This function simply plots a polynomial fit to scattered x,y data. This function can be used to easily add a linear trend line or other polynomial fit to a data plot.Syntaxpolyplot(x,y)polyplot(x,y,n)polyplot(...,'LineProperty',LineValue,...)polyplot(...,'error')polyplot(...,'error','ErrorLineProperty',ErrorLineValue)[h,p,delta] = polyplot(...)Descriptionpolyplot(x,y) places a least-squares linear trend line through scattered x,y data.polyplot(x,y,n) specifies the degree n of the polynomial fit to the x,y data. Default n is 1.polyplot(...,'LineProperty',LineValue,...) formats linestyle using LineSpec property name-value pairs (e.g., 'linewidth',3).polyplot(...,'error') includes lines corresponding to approximately +/- 1 standard deviation of errors delta. At least 50% of data should lie within the bounds of error lines.polyplot(...,'error','ErrorLineProperty',ErrorLineValue) formats error lines with line property name-value pairs. All arguments occurring after 'error' are assumed to be error line property specifications.[h,p,delta] = polyplot(...) returns handle(s) h of plotted line(s), coefficients p of polynomial fit p(x), and error estimate delta, which is the standard deviation of error in predicting a future observation at x by p(x). Assuming independent, normal, constant-variance errors, y +/- delta contains at least 50% of the predictions of future observations at x.
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