could not evaluate expression - Maple Help
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Error, (in plot/iplot2d/levelcurve) could not evaluate expression

 

Description

Examples

Description

This error occurs if Maple cannot evaluate the given expression to a numeric value when graphing with plots[contourplot].

Examples

> 

withplots:


Example 1

In this example, the wrong variable is used in the expression to be plotted.

> 

contourplotsinx⋅z,x=−3..3, y=−3..3

Error, (in plot/iplot2d/levelcurve) could not evaluate expression

 

Solution:

> 

contourplotsinx⋅y,x=−3..3, y=−3..3


Example 2

In the following example, the first argument passed to contourplot is a complex value, instead of a real value.

> 

contourplotx+I⋅y,x=−3..3,y=−3..3

Error, (in plot/iplot2d/levelcurve) could not evaluate expression

 

Solution:

To correct the error, pass only the real part of the complex value as an argument to contourplot.

> 

contourplotRex+I⋅y,x=−3..3,y=−3..3

See Also

plots[contourplot]

plots