Illegal type for X value: class java.lang.String (column 'Date')

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2

You could use this code in a propertyChange script to convert your string to a date:

from java.text import SimpleDateFormat

# set the format of the date string
format = SimpleDateFormat("MM/dd/yyyy")

# get the raw data
ds = event.source.parent.RawData     # This is your memory tag in a CustomProperty
ds2 = system.dataset.toPyDataSet(ds)

newRows = []
if len(ds2) > 0:
	# convert each row
	for row in ds2:
		dateStamp = format.parse(row[0])
		newRows.append([dateStamp, row[1]])
		
# create the new dataset
headers = ['Date', 'Value']
newDS = system.dataset.toDataSet(headers, newRows)

# write it to the Chart
event.source.parent.getComponent('Chart').Data = newDS