how to transform files into shapefile for qgis

I need to extrapolate some values to then be able to plot them on QGIS over a DEM.

I wrote with che command shapewrite:

contourf(XX,YY,ZZ,100,'linecolor','none'); where XX,YY,ZZ are 181x151 double

qgis1=contourf(XX,YY,ZZ,100,'linecolor','none'); where qgis1 is 2x2479 double

shapewrite(qgis1,"contour_5km.shp");

but it doesn't work and gives me this error back

Error using shapewrite

Expected input number 1, S, to be one of these types:

struct, table, mappoint, geopoint, mapshape, geoshape

Instead its type was double.

Error in shapewrite>parseInputs (line 667)

validateattributes(S, ...

Error in shapewrite (line 82)

[S, basename, dbfspec] = parseInputs(varargin{:});

Can anyone help me?

thanksss

[Eric Sofen]

Did you see this Answers post? How can I export a matlab contour as a polygon shapefile?

It looks like it has a clever solution to convert a contour to a shapefile.

[ELISABETTA BILLOTTA]

my problem is before. when i wrte shapefile give to me this error:

Error using shapewrite

Expected input number 1, S, to be one of these types:

struct, table, mappoint, geopoint, mapshape, geoshape

Instead its type was double.

Error in shapewrite>parseInputs (line 667)

validateattributes(S, ...

Error in shapewrite (line 82)

[S, basename, dbfspec] = parseInputs(varargin{:});

[Eric Sofen]

The contour2shape function in Walter's answer to the similar question should convert the matrix to a struct that shapewrite can then handle.