interpln
========

linear interpolation



Calling Sequence
~~~~~~~~~~~~~~~~


::

    [y]=interpln(xyd,x)




Arguments
~~~~~~~~~

:xyd 2 row matrix (xy coordinates of points)
: :x vector (abscissae)
: :y vector (y-axis values)
:



Description
~~~~~~~~~~~

given `xyd` a set of points in the xy-plane which increasing abscissae
and `x` a set of abscissae, this function computes `y` the
corresponding y-axis values by linear interpolation.



Examples
~~~~~~~~


::

    x=[1 10 20 30 40];
    y=[1 30 -10 20 40];
    `plot2d`_(x',y',[-3],"011"," ",[-10,-40,50,50]);
    yi=interpln([x;y],-4:45);
    `plot2d`_((-4:45)',yi',[3],"000");




See Also
~~~~~~~~


+ `splin`_ cubic spline interpolation
+ `interp`_ cubic spline evaluation function
+ `smooth`_ smoothing by spline functions


.. _splin: splin.html
.. _interp: interp.html
.. _smooth: smooth.html