The Numerical Derivative Calculator was created as an interactive tool to lend a hand in visualizing derivatives. The webpage was initially created by David Joiner and The Shodor Education Foundation, Inc. The operating system used while examining the site was Microsoft Windows XP Professional. Using the Internet Explorer and Mozilla Firefox browsers, the Numerical Derivative Calculator did not encounter any problems calculating derivatives or displaying graphs. On the site, located at http://www.shodor.org/refdesk/Resources/Models/NumericalDerivative/index.php# users are given the alternative to select either the Functions or Data version of the derivative calculator. When the preferred calculator is chosen, the user is then presented with a page to carry out applications. The Functions version of the calculator is used to study derivatives of known functions. Likewise, the Data variant is used to examine derivatives of measured data. Additional information that can be accessed on the site is instructions and the theory behind the calculator alongside key terms that are comprehensively defined.
Usability of the resource:Very usable Platform(s) tested:winxp Browser(s) tested:explorer, firefox
ValidationReview by CSERD Reviewer
Published / Modified 203 months 18 days ago
The approach used to enter data is especially user friendly and can be easily modified. To input the problem, users have to insert the function or data into a text box. From there, the minimum and maximum values of x are established and the number of points used in the calculation is input when using the Functional calculator. Both calculators allow the consumer to use a 2 point or 3 point derivative solution and graph up to the second derivative. In both variants, the more points that are selected give a more accurate answer. It seemed obvious that three hundred points in the Functional method was sufficient to see results, beyond that did not appear to change the graph. Furthermore, when using the Data calculator, the grid expands with the (x, y) values input. Moreover, the graphs that are generated by the calculator are accurate and precise. To validate the accuracy of the calculator, the results were compared to MATLAB, a math focused computer programming language. The results of the test can be seen below.
Usability of the resource:Very usable
AccreditationReview by Adam Moskowitz
Published / Modified 203 months 18 days ago
The appearance and display of the numerical derivative calculator is straight forward and easily understood. The adjustable parameters are easy to modify and the changes take effect when the derivative is re-calculated. In addition, there is noticeable change when toggling between the 3 point and 2 point derivative methods. Just like what is taught in math without computers, the 3 point method returns more accurate answers. The Numerical Derivative Calculator is a first-class tool that can be beneficial to students taking any level of calculus. The calculator can assist students with homework and teachers can apply it in the classroom. The graphs displayed are extremely accurate and can help students visualize derivatives. In saying that, the Numerical Derivative Calculator is a good resource that can enhance the learning experience for both the instructor and student.