topic Re: Binding Cursor with particular plot in LabWindows/CVI

Binding Cursor with particular plot

Gajanan — Fri, 15 Jul 2005 13:31:50 GMT

Hi,

I have ploted 6 plots on graph control and added 6 cursors. I want to bind the each cursor to particular plot, so that I can display 6 X and Y pairs on UI.

Any suggetion will be very heplful to me.

Gajanan

Re: Binding Cursor with particular plot

Wendy L — Mon, 18 Jul 2005 20:17:16 GMT

Hello Gajanan,

There isn't a function to restrict the cursor to a particular plot. You will have to do this programmatically. You can get the ID of the plot the cursor is currently over (if it is a snap-to-point cursor) with the GetGraphCursorIndex (panel, PANEL_GRAPH, eventData1, &plothandle, &index) function. The ID of the cursor that was moved will be passed in the eventData1 parameter. If the plotHandle is not the plot you want the cursor associated with, you can choose not to display the X/Y coordinates of the cursor on the UI and reset the cursor to a default location on a specified plot with the SetGraphCursorIndex function.

For instance, if you create two cursors and you want cursor 1 to be associated with plot 1 and cursor 2 to be associated with plot 2, you could do something like this:

        /* Get the cursor's position */
        GetGraphCursor (panel, PANEL_GRAPH, eventData1, &x, &y);

        /* Figure out which plot and which point the Cursor is over */
        GetGraphCursorIndex (panel, PANEL_GRAPH, eventData1, &plothandle, &index);

        if (plothandle == eventData1) {
        /* Display the data */
        SetCtrlVal (panel, PANEL_XREADOUT, x);
        SetCtrlVal (panel, PANEL_YREADOUT, y);
        SetCtrlVal (panel, PANEL_INDEX, index);
        printf("E1: %d, x: %f, y: %f, index: %d, plotHandle: %d\n",
           eventData1, x, y, index, plothandle);
        } else SetGraphCursorIndex(panel, PANEL_GRAPH, eventData1, eventData1, 0);

Thanks.

Message Edited by Wendy L on 07-18-2005 03:18 PM

Re: Binding Cursor with particular plot

Gajanan — Tue, 19 Jul 2005 06:08:08 GMT

Thanks Wendy.

Re: Binding Cursor with particular plot

raj1 — Tue, 19 Jul 2005 06:44:33 GMT

hello,

I would like to plot a   XY graph with small text near by plotted points .Ofcourse I tried with PlotText ()
but it takes much time to display text with each point in the graph. Is it possible to plot XY graph with text at each point   ???

I am reading a binary file which has an array with many elements (approx. more than 1 million)(each element of this arrray is a structure)
for example first element of myarray is myarray[ 0]. x,   myarray[0].y,     myarray[0].text1,   myarray[0].text2

I am reading the file element by element until the end of file and copying the values to different arrays for plotting a graph
   For ex: first elements of different arrays            Xarray[0]= myarray[ 0]. x
                                                                         Yarray[0]= myarray[ 0].y
                                                                            Text1array[0][50]= myarray[ 0].text1
                                                                      Text2array[0][50]= myarray[ 0].text2
Now I am using PlotPoint and PlotText for plotting XY graph with empty square points and for displaying my texts at each point (text1 , text2 of my Textarrays) inside the reading loop ( reading binary file ).
It is very slow if I use these PlotPoint and PlotText inside the reading loop.
I tried with PlotXY   to plot XY graph with empty square by giving Xarray and Yarray (after finishing the reading binary file ). It is very fast if I use only PlotXY(without displaying text at each point). But now I am still using PlotText inside the reading file routine(for displaying text at each point). So it is again very slow because of PlotText inside reading routine.
Is it possible to display text at each point at a time( like PlotXY ) by giving Xarray , Yarray and Text1array
Text1array[ ][ ] =   {   "xyz"
                           "abc"
                              "def"
                                  .......
                       ....... }

"xyz" at first point , "abc" at second point , so on............
    Any suggessions...................???

Re: Binding Cursor with particular plot

Wendy L — Tue, 19 Jul 2005 17:40:34 GMT

Hello rajj,

Refer to the following post.

Thanks.

Re: Binding Cursor with particular plot

Martin_Manger — Mon, 05 Sep 2005 09:06:35 GMT

Hello raj1,

maybe it should help, if you make the graph invisible with SetCtrlAttribute (panelHandle, controlID, ATTR_VISIBLE, 0) and then plot all the points and text. After plotting, you make the graph visible with SetCtrlAttribute (panelHandle, controlID, ATTR_VISIBLE, 1).
This should accelerate the plot.

Best regards,

Martin