Automatic Curve Matching

Match any aquifer test solution objectively and efficiently using automatic curve matching. uses nonlinear weighted least-squares with singular-value decomposition to determine the optimal match between an aquifer test solution and your data.

Other useful options for automatic curve matching include curve fitting within a specified time window and matching only specified wells in your monitoring network.

Nonlinear Least-Squares Curve Matching

Since its first release in 1989, has led the way with the integration of visual and automatic curve-matching methods into a single software package for the analysis of aquifer test data.

employs a powerful method of nonlinear weighted least-squares curve fitting (Marquardt 1963) to find the optimal match between solution curves and aquifer test data.

Only combines automatic curve matching with informative statistical analyses to help you see how well your model fits the data.

Singular-Value Decompositionnew2.gif (111 bytes)

now includes singular value decomposition (SVD), a powerful technique that improves the convergence of automatic curve matching (Press et al. 2002). When SVD is invoked, parameter corrections are dampened by eliminating insensitive components from the updating equations.

SVD can yield convergence in certain difficult problems where other curve fitting algorithms may fail.

Match Within Time Windownew2.gif (111 bytes)

Select time window

Choose a time window for automatic curve matching.

In some instances, it is advantageous to match an aquifer test solution over a specified range of time. makes it easy with a time window for automatic estimation.

Match Group of Wellsnew2.gif (111 bytes)

Select group of wells

Quickly select wells to include or exclude from automatic curve matching.

allows you to analyze more than one observation well in pumping tests and slug tests. In the Active Wells property sheet, you may choose which wells to match during automatic estimation.