Vernier LabQuest 2 - Manual (Page 25)

LabQuest App
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Integral – The Integral tool numerically
integrates graphed data. Select a region, if
needed, and choose Integral from the Analyze
menu. Enable the tool by tapping on the
displayed sensor or column name. The integral
is drawn and the numeric result is displayed in a
panel to the right of the graph.
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Statistics – The Statistics tool displays statistics
for graphed data. Select a region, if needed, and
choose Statistics from the Analyze menu.
Enable the tool by tapping on the displayed
sensor or column name. Descriptive statistics are
displayed in a panel to the right of the graph. If a
region is selected, brackets are drawn to indicate
the region used for calculations.
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Delta – The Delta tool opens a preview window
where you can examine x- and y-deltas. Choose
Delta from the Analyze menu to open the
preview window. Then, tap and drag to create a
box overlaid on the graph. The vertical side of
the box yields
∆y, and the horizontal side of the
box yields
∆x. Tap OK to keep these values and
display the box on the Graph screen. To exit the
Delta tool without displaying the box on the
Graph screen, tap Cancel.
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Curve Fit – The Curve Fit tool fits a chosen
function to your data. If a region of the graph is
selected, only that region is used for fitting. If
there is no selection, the entire graph is used.
Choose Curve Fit from the Analyze menu. In the
Choose Fit list, choose the desired equation.
LabQuest displays the fit in the preview graph at
the left. The fit coefficients and Root Mean
Square Error (RMSE) are also displayed. Tap
OK to keep this fit and display the curve on the Graph screen. To exit the Curve Fit tool
without applying the curve, tap Cancel.
Tip: The RMSE (root mean square error) is a
measure of how well the fit matches the data.
The smaller the RMSE, the closer the data are to
the fitted line. The RMSE has the same units as
the y-axis data.
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Interpolate – Once you have performed a curve
fit, you can use the Interpolate tool to read
values from the fitted function. Choose