PASCO Xplorer-GLX Users’ Guide - Manual (Page 25)

X p l o r e r G L X U s e r s ’ G u i d e 19
Slope Tool Select the Slope Tool from the Tools menu to measure the slope of
a tangent line at one point on the data plot. A pair of crosshairs marks the point at
which the slope is measured. Labels on the Graph’s edges show the coordinates
of the point, and the slope is displayed at the bottom of the screen.
Use the left and right arrow keys to move the Slope Tool to adjacent points. Use
the up and down arrow keys to send it to the first and last points. Press and hold
the left or right arrow key to move the Slope Tool quickly.
If you have a mouse, you can move the Slope Tool by dragging the circle
at the intersection of the cross hairs left and right.
Statistics Select Statistics from the Tools menu to put the Graph into Statistics
mode. The Graph displays the minimum, maximum, average, and standard devi-
ation (
σ) of the data inside the region of interest (ROI), which is indicated by a
dashed box.
Statistics mode
Two cursors designate the left and right sides of the ROI. The larger cursor is the
active one and can be moved with the arrow keys or mouse.
4 As the active cursor
moves, one side of the box moves with it.
The smaller cursor indicates the side of the ROI that does not move.
To switch the active cursor to the other side of the box, hold and press .
Linear Fit When Linear Fit is selected from the Tools menu, a best-fit line is
applied to the data in the ROI. (See “Statistics” above for instructions on setting
the ROI.)
The slope, the Y-intercept, the mean squared error (MSE), and the root mean
squared error
of the linear fit are displayed at the bottom of the screen
along with the correlation coefficient (r) of the data in the ROI.
Positive DX and DY Negative DX and DY
When the cursors swap places, the signs of ∆ X and ∆ Y change
X Y
Slope
Tool
Slope
Slope Tool
Statistics
Region of interest
Stationary
Cursor
Active
Cursor
4 See page 16 for detailed instructions on
moving the cursor with the keypad or
mouse.
Esc Õ
Region of interest
Linear Fit
MSE
( )