This message is generated when an element that is not a real number is encountered while generating contour lines for a ContourGraphics expression.
The first argument in ContourGraphics is expected to be an array of real numbers.
This message can result from evaluating ContourPlot or any other function that constructs a ContourGraphics expression and causes contours to be computed for that expression.
Off[message] switches off the message; On[message] switches it on. For example: Off[ContourGraphics::ctpnt].
Examples
Basic Examples(1)
One of the elements in the first argument of ContourGraphics is not a number: