Graphs and Charts (G Dataflow)

What Is the Difference between Graphs and Charts?

You can collect data, usually in an array, and then plot the data to a graph. This process is similar to a spreadsheet that first stores the data and then generates a plot of it.

A chart appends new data points to those points already in the display to create a history. On a chart, you can see the current reading or measurement in context with data previously acquired.

Deciding Which Graph or Chart to Use

Knowing what type of data you need to display determines the type of graph or chart you should use.

Control	Accepted Data Types	Display Examples	When to Use
Graph	Numeric, complex, X/Y, or point sample data contained in arrays and analog waveforms	Analog waveform data acquired at a constant rate	Use a graph for fast processes that acquire data continuously.
Chart	Numeric data contained in arrays and analog waveforms	Analog waveform data acquired at a constant rate with a history, or buffer, of the data from previous updates	Use a chart for processes that require a cumulative history of incremental updates to be maintained.
Intensity Graph	3D data on a 2D plot by using color to display the values of the third dimension	Patterned data, such as frequency of sound intensity	Use an intensity graph for 3D data.

Autoscaling

You can enable autoscaling for graphs and charts, which means they adjust their horizontal or vertical scales to fit the data you wire to them. Graphs and charts support the following types of autoscaling:

• Fit exactly—Fits the end markers to the exact minimum and maximum values of the data.
• Fit loosely—Rounds the end markers to a multiple of the increment used for the scale.
• Grow only—Fits the end markers to the minimum and maximum values of the data at run time. This type of autoscaling is available only for the vertical axis of graph, chart, and intensity graph.