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Table Graph
Add a Table Graph () plot to display data from a table with one line per output column. Right-click a 1D Plot Group, Polar Plot Group, or Smith Plot Group to add this plot type. First define a table to plot. This plot is also available from the plot groups’ contextual ribbon toolbars, by clicking Graph Plot on the Evaluation Group contextual ribbon toolbar (to plot the evaluation group in graph plot), or by selecting Table Graph () from the Table window’s toolbar.
Go to Common Results Node Settings for links to information about the Coloring and Style section.
Data
From the Source list, choose Table or Evaluation group, and then choose a table or evaluation group table with the data that you want to plot as a surface plot from the list below.
From the x-axis data list (or θ angle data for polar plots), select the column to use as x-axis: Select Row index to use the table’s row indexes (row numbers) as x-axis, or leave it at Automatic to let the software determine the input from the data in the table.
The Plot columns list controls which columns to plot. All excluding x-axis (or All excluding θ angle list for polar plots) indicates all columns not used in x-axis data (or θ angle data). Select Manual instead to specify which columns to plot in the Columns list.
If available, select a Transformation of the data from the table — None (the default) to use the data directly without any transformation, or select Frequency spectrum to use an FFT (fast Fourier transform) to transform the data from a time-dependent solution to the frequency domain.
If Frequency spectrum is selected, the default number of frequencies and frequency range depend on the data, and usually those values do not need changing, but if desired, you can specify these values manually:
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Select the Number of frequencies check box and enter a value in the associated field (the default is based on the number of time samples).
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Select the Frequency range check box and then enter the bounds of the frequency range in the Minimum and Maximum fields (in Hz). The FFT algorithm uses resampling based on linear interpolation. The x-axis shows the frequency (in Hz). By default, the y-axis shows the unscaled Fourier coefficients.
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Select the Scale check box to scale the values on the y-axis so that their magnitude reflects the magnitude of the original signal. The values then have the same unit as the input data for the FFT. The y-axis title includes the unit if all expressions represented on the y-axis have the same unit. The scaling makes the magnitude at 0 Hz equal to the bias or DC component of the original signal. For a pure sinusoid, the scaled value is the peak magnitude divided by the square root of 2 ().
Use the Sorting list to sort the sort the data points with respect to x- or y-coordinates. Choose None (the default, no sorting), x-axis data, or y-axis data.
By default, table plots only display the real data in a table, just as other plot types display real data unless you use the imag function in the expression. To display the imaginary part of complex-valued data in a table, when available, select the Plot imaginary part check box. This option is only available when a transformation to the frequency domain is not used.
In the settings for a Smith Plot Group, this section includes a Data interpretation list, where you can choose Reflection (the default), Impedance, or Admittance.
y-Axis
This section is only available if the Two y-axes check box is selected in the Plot Settings section of the parent 1D Plot Group node’s Settings window.
Select the Plot on secondary y-axis check box to plot the y-axis data on the secondary y-axis to the right of the plot instead of the primary y-axis to the left of the plot.
Preprocessing
This section contains settings to preprocess the data in the table graph by scaling and shifting the data values, which can be useful to match data from different sources or to scale some data to express the values in another unit, for example.
Under x-axis column and y-axis column, from the Preprocessing list select:
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None (the default), for no preprocessing of the data.
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Linear, to preprocess the data using a linear transformation of the data values for the x- or y-axis column. You define the linear preprocessing with values for the scaling (default: 1) and the shift or offset (default: 0) in the Scaling and Shift fields, respectively. The default values do not change the original data values.
Legends
Select the Show legends check box to display the plotted expressions to the right of the plot. In plots where each line represents a certain time value, eigenvalue, or parameter value, these values are also displayed.
When Automatic is selected from the Legends list (the default), the legend texts appear automatically. You can add a prefix or a suffix to the automatic legend text in the Prefix and Suffix fields. If Manual is selected from the Legends list, enter your own legend text into the table.