Pv.SetAxis()

Type: INSTANCE FUNCTION

Purpose: Helps to define the real-time display of a PV object.

Associates an axis with a data column in the object. Controls linear/logarithmic display formatting and allows labeling of the axis.

You must call Pv.SetAxis for each of the axes in the rea-time plot. For a y and y' versus x plot, you need three calls to Pv.SetAxis().

Usage:

Pv.SetAxis(AxisNo, Source, Scale, MinVal, Label, Units)
     
AxisNo INDEX

Use the constants below to define which axis is being configured.

X_AXIS x-axis

Y_AXIS y-axis (y-vs-x plot) or Lower Y (y, y'-vs-x)

Z_AXIS Upper y-axis (y, y'-vs-x only)

Source INDEX The column number containing the data to be plotted, or use the predefined constants defined in Pv.DataCol().
Scale INDEX

LIN_AXIS The axis is linear

LOG_AXIS The axis is logarithmic

MinVal REAL

Minimum value used in prevention of "ugly" plot scaling. MinVal is used differently depending on Scale setting.

On a linear axis, this is the minimum resolution of the plot. The range of values shown on the axis cannot be smaller than MinVal. This prevents excessively fine scaling when plotting data where all the values are identical or very similar.

On a logarithmic axis, this value is substituted for 0's in the data. This prevents infinite logarithmic values.

Label STRING The label used for the axis. Short names (one or two character labels are preferred).
Units STRING The units used for the axis. Short names (one or two character labels are preferred).

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