widgy,
You can format numbers and date time values before they appear on Axis-X using its valueFormatString property. Here is an example on how you can use axisX valueFormatString property:
axisX: {
valueFormatString: "DD/MMM/YYYY HH:mm:ss",
}
Please note that the xValueFormatString property is used for formatting x-values in indexLabel and toolTip.
I thought that would have changed the label as well since it says “Defines how x axis values must be formatted before they appear on the indexLabel or toolTip.
That was a typo and we have fixed the same. Thank you for reporting :)
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Anjali