Wolfram Demonstrations Project

Initially there is one locator, representing a point in a region defined by the popup menu "axes scale". Each point is labeled

, where

is the current number of the locator,

is its vertical coordinate, and

is the uncertainty of

as set by the slider. The popup menu "point" connects a point

to the "uncertainty" slider. Deleting locators reorders the numbers and the "point" number jumps to zero, which means the slider is not connected to any point.

The controls let you:
• select one of the Mathematica built-in functions Fit, Interpolation, or InterpolatingPolynomial
• change the axes scale to vary the range of the plot in steps from

• select the color of the interpolation curve
• select the order of interpolation; changing the function to InterpolatingPolynomial automatically adjusts this parameter
• connect the "point" popup menu with the uncertainty slider

Contributed by: Valter Yoshihiko Aibe and Mikhail Dimitrov Mikhailov, INMETRO, Brazil

Drag Locators
Create and Delete Locators

The rules given in the initialization section are borrowed from the Uncertain Calculus, introduced in [1].

The Demonstration combines Demonstrations [2] to [5], interpolating

and extending them to work with uncertain numbers for

, explored also in [6] and [7].
In general, both

and

in a measured function are uncertain numbers

and

, but here it is assumed that

. This assumption is based on the possibility to transfer the uncertainty

to the enlarged uncertain

of the uncertain number

, where

[8, p. 125]. Here

is an estimated value of the derivative

that could be obtained by successive approximations.

References:

[1] V. Y. Aibe and M. D. Mikhailov, "Uncertainty Calculus in Metrology," Proceedings of ENCIT 2008, 12th Brazilian Congress of Thermal Engineering and Sciences, Belo Horizonte, MG, Brazil, November 10–14, 2008.

[2] Interpolating Polynomial

[3] Interpolating a Set of Data

[4] Fitting a Curve to Five Points

[5] Curve Fitting

[6] Solving Matrix Systems with Real, Interval, or Uncertain Elements

[7] Area, Perimeter, and Diagonal of a Rectangle with Uncertain Sides

[8] José Henrique Vuolo, Fundamentos da Teoria de Erros, 2nd ed., 2nd printing, Sao Paulo, Brazil: Edgar Blucher, LTDA, 2000.