title: How to regrid a netCDF using bilinear interpolation?
body: <p>I am looking for a procedure to apply bilinear interpolation to change the resolution of netCDF file <code>(1.5°x1.5°) ---&gt; (1.25°x0.9375°)</code></p>
  
  <p>Edit:</p>
  
  <p>I have been reading some pages and I found a function called <code>remapbil</code>. It comes from <code>Climate Data Operator (CDO)</code>. I tried to do the regrid but it did not work. This is my netCDF file info:</p>
  
  <pre><code>    File format: netCDF
      -1 : Institut Source   Ttype    Levels Num  Gridsize Num Dtype : Parameter name
       1 : unknown  unknown  instant       1   1       180   1  I16  : tp            
     Grid coordinates :
       1 : lonlat       &gt; size      : dim = 180  nx = 12  ny = 15
                          longitude : first = 279  last = 295.5  inc = 1.5  degrees_east
                          latitude  : first = 15  last = -6  inc = -1.5  degrees_north
     Vertical coordinates :
       1 : surface                  : 0 
     Time coordinate :  324 steps
       RefTime =  1900-01-01 00:00:00  Units = hours  Calendar = standard
    YYYY-MM-DD hh:mm:ss  YYYY-MM-DD hh:mm:ss  YYYY-MM-DD hh:mm:ss  YYYY-MM-DD hh:mm:ss
    1979-01-01 03:00:00  1979-02-01 03:00:00  1979-03-01 03:00:00  1979-04-01 03:00:00
    1979-05-01 03:00:00  1979-06-01 03:00:00  1979-07-01 03:00:00  1979-08-01 03:00:00
    1979-09-01 03:00:00  1979-10-01 03:00:00  1979-11-01 03:00:00  1979-12-01 03:00:00
    1980-01-01 03:00:00  1980-02-01 03:00:00  1980-03-01 03:00:00  1980-04-01 03:00:00
    1980-05-01 03:00:00  1980-06-01 03:00:00  1980-07-01 03:00:00  1980-08-01 03:00:00
    1980-09-01 03:00:00  1980-10-01 03:00:00  1980-11-01 03:00:00  1980-12-01 03:00:00
    1981-01-01 03:00:00  1981-02-01 03:00:00  1981-03-01 03:00:00  1981-04-01 03:00:00
    1981-05-01 03:00:00  1981-06-01 03:00:00  1981-07-01 03:00:00  1981-08-01 03:00:00
    1981-09-01 03:00:00  1981-10-01 03:00:00  1981-11-01 03:00:00  1981-12-01 03:00:00
    1982-01-01 03:00:00  1982-02-01 03:00:00  1982-03-01 03:00:00  1982-04-01 03:00:00
    1982-05-01 03:00:00  1982-06-01 03:00:00  1982-07-01 03:00:00  1982-08-01 03:00:00
    1982-09-01 03:00:00  1982-10-01 03:00:00  1982-11-01 03:00:00  1982-12-01 03:00:00
    1983-01-01 03:00:00  1983-02-01 03:00:00  1983-03-01 03:00:00  1983-04-01 03:00:00
    1983-05-01 03:00:00  1983-06-01 03:00:00  1983-07-01 03:00:00  1983-08-01 03:00:00
    1983-09-01 03:00:00  1983-10-01 03:00:00  1983-11-01 03:00:00  1983-12-01 03:00:00
    1984-01-01 03:00:00  1984-02-01 03:00:00  1984-03-01 03:00:00  1984-04-01 03:00:00
    1984-05-01 03:00:00  1984-06-01 03:00:00  1984-07-01 03:00:00  1984-08-01 03:00:00
    1984-09-01 03:00:00  1984-10-01 03:00:00  1984-11-01 03:00:00  1984-12-01 03:00:00
    1985-01-01 03:00:00  1985-02-01 03:00:00  1985-03-01 03:00:00  1985-04-01 03:00:00
    1985-05-01 03:00:00  1985-06-01 03:00:00  1985-07-01 03:00:00  1985-08-01 03:00:00
    1985-09-01 03:00:00  1985-10-01 03:00:00  1985-11-01 03:00:00  1985-12-01 03:00:00
    1986-01-01 03:00:00  1986-02-01 03:00:00  1986-03-01 03:00:00  1986-04-01 03:00:00
    1986-05-01 03:00:00  1986-06-01 03:00:00  1986-07-01 03:00:00  1986-08-01 03:00:00
    1986-09-01 03:00:00  1986-10-01 03:00:00  1986-11-01 03:00:00  1986-12-01 03:00:00
    1987-01-01 03:00:00  1987-02-01 03:00:00  1987-03-01 03:00:00  1987-04-01 03:00:00
    1987-05-01 03:00:00  1987-06-01 03:00:00  1987-07-01 03:00:00  1987-08-01 03:00:00
    1987-09-01 03:00:00  1987-10-01 03:00:00  1987-11-01 03:00:00  1987-12-01 03:00:00
    1988-01-01 03:00:00  1988-02-01 03:00:00  1988-03-01 03:00:00  1988-04-01 03:00:00
    1988-05-01 03:00:00  1988-06-01 03:00:00  1988-07-01 03:00:00  1988-08-01 03:00:00
    1988-09-01 03:00:00  1988-10-01 03:00:00  1988-11-01 03:00:00  1988-12-01 03:00:00
    1989-01-01 03:00:00  1989-02-01 03:00:00  1989-03-01 03:00:00  1989-04-01 03:00:00
    1989-05-01 03:00:00  1989-06-01 03:00:00  1989-07-01 03:00:00  1989-08-01 03:00:00
    1989-09-01 03:00:00  1989-10-01 03:00:00  1989-11-01 03:00:00  1989-12-01 03:00:00
    1990-01-01 03:00:00  1990-02-01 03:00:00  1990-03-01 03:00:00  1990-04-01 03:00:00
    1990-05-01 03:00:00  1990-06-01 03:00:00  1990-07-01 03:00:00  1990-08-01 03:00:00
    1990-09-01 03:00:00  1990-10-01 03:00:00  1990-11-01 03:00:00  1990-12-01 03:00:00
    1991-01-01 03:00:00  1991-02-01 03:00:00  1991-03-01 03:00:00  1991-04-01 03:00:00
    1991-05-01 03:00:00  1991-06-01 03:00:00  1991-07-01 03:00:00  1991-08-01 03:00:00
    1991-09-01 03:00:00  1991-10-01 03:00:00  1991-11-01 03:00:00  1991-12-01 03:00:00
    1992-01-01 03:00:00  1992-02-01 03:00:00  1992-03-01 03:00:00  1992-04-01 03:00:00
    1992-05-01 03:00:00  1992-06-01 03:00:00  1992-07-01 03:00:00  1992-08-01 03:00:00
    1992-09-01 03:00:00  1992-10-01 03:00:00  1992-11-01 03:00:00  1992-12-01 03:00:00
    1993-01-01 03:00:00  1993-02-01 03:00:00  1993-03-01 03:00:00  1993-04-01 03:00:00
    1993-05-01 03:00:00  1993-06-01 03:00:00  1993-07-01 03:00:00  1993-08-01 03:00:00
    1993-09-01 03:00:00  1993-10-01 03:00:00  1993-11-01 03:00:00  1993-12-01 03:00:00
    1994-01-01 03:00:00  1994-02-01 03:00:00  1994-03-01 03:00:00  1994-04-01 03:00:00
    1994-05-01 03:00:00  1994-06-01 03:00:00  1994-07-01 03:00:00  1994-08-01 03:00:00
    1994-09-01 03:00:00  1994-10-01 03:00:00  1994-11-01 03:00:00  1994-12-01 03:00:00
    1995-01-01 03:00:00  1995-02-01 03:00:00  1995-03-01 03:00:00  1995-04-01 03:00:00
    1995-05-01 03:00:00  1995-06-01 03:00:00  1995-07-01 03:00:00  1995-08-01 03:00:00
    1995-09-01 03:00:00  1995-10-01 03:00:00  1995-11-01 03:00:00  1995-12-01 03:00:00
    1996-01-01 03:00:00  1996-02-01 03:00:00  1996-03-01 03:00:00  1996-04-01 03:00:00
    1996-05-01 03:00:00  1996-06-01 03:00:00  1996-07-01 03:00:00  1996-08-01 03:00:00
    1996-09-01 03:00:00  1996-10-01 03:00:00  1996-11-01 03:00:00  1996-12-01 03:00:00
    1997-01-01 03:00:00  1997-02-01 03:00:00  1997-03-01 03:00:00  1997-04-01 03:00:00
    1997-05-01 03:00:00  1997-06-01 03:00:00  1997-07-01 03:00:00  1997-08-01 03:00:00
    1997-09-01 03:00:00  1997-10-01 03:00:00  1997-11-01 03:00:00  1997-12-01 03:00:00
    1998-01-01 03:00:00  1998-02-01 03:00:00  1998-03-01 03:00:00  1998-04-01 03:00:00
    1998-05-01 03:00:00  1998-06-01 03:00:00  1998-07-01 03:00:00  1998-08-01 03:00:00
    1998-09-01 03:00:00  1998-10-01 03:00:00  1998-11-01 03:00:00  1998-12-01 03:00:00
    1999-01-01 03:00:00  1999-02-01 03:00:00  1999-03-01 03:00:00  1999-04-01 03:00:00
    1999-05-01 03:00:00  1999-06-01 03:00:00  1999-07-01 03:00:00  1999-08-01 03:00:00
    1999-09-01 03:00:00  1999-10-01 03:00:00  1999-11-01 03:00:00  1999-12-01 03:00:00
    2000-01-01 03:00:00  2000-02-01 03:00:00  2000-03-01 03:00:00  2000-04-01 03:00:00
    2000-05-01 03:00:00  2000-06-01 03:00:00  2000-07-01 03:00:00  2000-08-01 03:00:00
    2000-09-01 03:00:00  2000-10-01 03:00:00  2000-11-01 03:00:00  2000-12-01 03:00:00
    2001-01-01 03:00:00  2001-02-01 03:00:00  2001-03-01 03:00:00  2001-04-01 03:00:00
    2001-05-01 03:00:00  2001-06-01 03:00:00  2001-07-01 03:00:00  2001-08-01 03:00:00
    2001-09-01 03:00:00  2001-10-01 03:00:00  2001-11-01 03:00:00  2001-12-01 03:00:00
    2002-01-01 03:00:00  2002-02-01 03:00:00  2002-03-01 03:00:00  2002-04-01 03:00:00
    2002-05-01 03:00:00  2002-06-01 03:00:00  2002-07-01 03:00:00  2002-08-01 03:00:00
    2002-09-01 03:00:00  2002-10-01 03:00:00  2002-11-01 03:00:00  2002-12-01 03:00:00
    2003-01-01 03:00:00  2003-02-01 03:00:00  2003-03-01 03:00:00  2003-04-01 03:00:00
    2003-05-01 03:00:00  2003-06-01 03:00:00  2003-07-01 03:00:00  2003-08-01 03:00:00
    2003-09-01 03:00:00  2003-10-01 03:00:00  2003-11-01 03:00:00  2003-12-01 03:00:00
    2004-01-01 03:00:00  2004-02-01 03:00:00  2004-03-01 03:00:00  2004-04-01 03:00:00
    2004-05-01 03:00:00  2004-06-01 03:00:00  2004-07-01 03:00:00  2004-08-01 03:00:00
    2004-09-01 03:00:00  2004-10-01 03:00:00  2004-11-01 03:00:00  2004-12-01 03:00:00
    2005-01-01 03:00:00  2005-02-01 03:00:00  2005-03-01 03:00:00  2005-04-01 03:00:00
    2005-05-01 03:00:00  2005-06-01 03:00:00  2005-07-01 03:00:00  2005-08-01 03:00:00
    2005-09-01 03:00:00  2005-10-01 03:00:00  2005-11-01 03:00:00  2005-12-01 03:00:00
  </code></pre>
  
  <p>Then, my problem is that I don not know how to type the target grid such this:</p>
  
  <pre><code>cdo remapbil,r180x360 input_file.nc output_file.nc
  </code></pre>
  
  <p>I will really appreciate your help.</p>