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Line style of time series marker line. Enumeration of "solid", "none", "bar", "dashdot", "dashed", "dotted", "solid;thick", "dashdot;thick", "dashed;thick"; "dotted;thick"; "area"; "constant".
The "constant" label should preferably only be applied if the time series holds only one value.
label
Define the name of time series marker line.
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