Exponential Fit Coefficients (Not in Base Package)

Finds the set of exponential coefficients amplitude and damping, which describe the exponential curve that best represents the input data set using the least-squares solution. This VI is a subVI of the Exponential Fit VI. Details  

	Y must contain at least two points. The points must have the same sign and be nonzero values. That is, yi > 0 for i = 0, 1, … n – 1 or yi < 0 for i = 0, 1, …n – 1, n 2, where Y represents the input sequence Y and n is the number of data points. If the signs are inconsistent, the values are zero, or there are less than two sample points, the VI sets amplitude and damping to NaN and returns an error.
	X must contain at least two points. n is greater than or equal to 2, where n is the number of data points.
	amplitude is the amplitude of Best Exponential Fit.
	damping is the damping constant of Best Exponential Fit.
	error returns any error or warning from the VI. You can wire error to the Error Cluster From Error Code VI to convert the error code or warning into an error cluster.

Exponential Fit Coefficients Details

The following equation gives the general form of the exponential fit.

where F is the sequence representing the best fitted values, X represents the input sequence X, a is the amplitude, and is the damping constant.

Note  This VI performs an exponential fit even when the elements of Y are negative. The VI performs the fit under the assumption that the amplitude coefficient is also negative and returns a negative amplitude. Y cannot be a mixture of positive and negative elements, and all elements of Y must be nonzero values.