set waveform chart?

[maji]

I have 2 Questions with Labview 8.5:

1-How can i use a Waveform Chart for display 2 signals in one chart with current time?
    I want X axis be current time?please describe me with an example.

2-How can i set a waveform chart for display Empty data?
    i want set my chart to don't display any signal when my chart don't receive data when changing the time axis.

Thanks.

[CoastalMaineBird]

I want X axis be current time?please describe me with an example. 

I have a blog entry for displaying time-of-day on a waveform chart.  Look for KEEPING YOUR CHARTS UP TO DATE.

i want set my chart to don't display any signal when my chart don't receive data when changing the time axis. 

Set the HISTORY data to an empty array.  (The blog entry shows how to do that, too).

[maji]

hi CoastalMaineBi…

i think your method

Keeping your charts up to date

have a problem:
new data isn't on new time and new time is on first data.
i need a chart that change new data with new time Simultaneous.

please help me.

[maji]

hi

How can i Set the HISTORY data to an empty array?

THANKS.

[CoastalMaineBird]

See the blog post.  The very first thing to do is set the HISTORY DATA (property of the chart) to an empty array of whatever type of data you feed it.

[CoastalMaineBird]

new data isn't on new time and new time is on first data.

I don't know what you mean.

When you start, the plots are empty and the X-axis on the left is the current time.

The X-axis on the right is one minute from now (or whatever you choose).

As the plots fill up, they correspond with the time on the X axis.

When the plots get full, the X-axis scrolls, and the leading edge of the plot always corresponds to the current time.