gdk-device-axis-value (device axes axis-label)

device -- a gdk-device object for a pointer device
axes -- a list of double float of axes
axis-label -- an atom as a string with the axis label

A double float with the found value, or nil.

Interprets a list of double floats as axis values for a given device, and locates the value in the array for a given axis label, as returned by the gdk-device-list-axes function.