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Simulink.sdi.getCursorPositions

Get position for active cursors in the Simulation Data Inspector

Since R2021a

    Description

    t1 = Simulink.sdi.getCursorPositions returns the value of the leftmost active cursor in the Inspect pane of the Simulation Data Inspector. Assign the return to a single output when one cursor is active.

    t1 = Simulink.sdi.getCursorPositions(view) returns the value of the leftmost active cursor in the Inspect or Compare pane of the Simulation Data Inspector according to view. Assign the return to a single output when one cursor is active.

    example

    [t1,t2] = Simulink.sdi.getCursorPositions returns the positions of the active cursors in the Inspect pane of the Simulation Data Inspector.

    [t1,t2] = Simulink.sdi.getCursorPositions(view) returns the positions of the active cursors in the Inspect or Compare pane of the Simulation Data Inspector according to view.

    Examples

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    You can use the Simulation Data Inspector programmatic interface to specify the position of cursors on time plots or sparklines and to access the time that corresponds to the current cursor position.

    Open the session file vdp_mu.mldatx to add plot data in the Simulation Data Inspector. The session file contains data for a 20-second simulation of a model of the Van der Pol equation, with signals x1 and x2 plotted on separate subplots in a 2-by-1 subplot layout.

    openExample("simulink/InteractWithCursorsInTheSimulationDataInspectorExample", ...
        supportingFile="vdp_mu.mldatx")

    Use the Simulink.sdi.setNumCursors function to add one cursor to the plot.

    Simulink.sdi.setNumCursors(1);

    Suppose you want to know the signal values 5 seconds into the simulation. Use the Simulink.sdi.setCursorPositions function to move the cursor to t=5s and read the signal values off from the cursor on each subplot. The asterisk next to the value in the cursor label indicates that the value is interpolated because the simulation did not include a calculation for a simulation time of exactly 5s.

    Simulink.sdi.setCursorPositions('left',5);

    Subplots of x1 on the top and x2 on the bottom showing the data cursor at 5 seconds.

    Suppose you want to calculate the time between two peaks in the x2 signal. Add a second cursor using the Simulink.sdi.setNumCursors function or by using Show/hide data cursors in the Simulation Data Inspector.

    numCursors = Simulink.sdi.getNumCursors;
    if(numCursors < 2)
        Simulink.sdi.setNumCursors(2);
    end

    Drag the cursors so the left cursor is positioned at the first peak in the x2 signal and the right cursor is positioned at the second peak. Alternatively, you can run this code that positions the cursors for you.

    Simulink.sdi.setCursorPositions('left',5.921998549931304,...
        'right',12.378442136906246);

    Subplots of x1 on the top and x2 on the bottom with two cursors.

    The Simulation Data Inspector displays the difference between the two cursors in seconds. However, the cursor position and difference values are both rounded. Use the Simulink.sdi.getCursorPositions function to programmatically retrieve the exact time values that correspond to the cursor positions. Then, compute the difference between the times.

    [t1,t2] = Simulink.sdi.getCursorPositions;
    T = t2 - t1
    T = 6.4564

    Input Arguments

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    Plot area for which to return cursor positions, specified as 'inspect' or 'compare'.

    Example: [t1,t2] = Simulink.sdi.getCursorPositions('compare') returns the positions of two cursors on the Compare pane of the Simulation Data Inspector.

    Data Types: char | string

    Output Arguments

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    Left cursor position, returned as a scalar. When no cursors are active in the plot area specified by view, the value for t1 is returned as NaN.

    Cursor identities are relative, not absolute. If the left cursor moves to the right of the right cursor, the left cursor becomes the right cursor and vice versa.

    Right cursor position, returned as a scalar. When fewer than two cursors are active in the plot area specified by view, the value for t1 is returned as NaN.

    Cursor identities are relative, not absolute. If the left cursor moves to the right of the right cursor, the left cursor becomes the right cursor and vice versa.

    Version History

    Introduced in R2021a