griddata (version 0.1.1)
index
/Volumes/User/jsw/python/natgrid/lib/griddata/griddata.py

 
Modules
       
matplotlib.numerix
matplotlib.numerix.ma

 
Functions
       
griddata(x, y, z, xi, yi, masked=False, fill_value=1e+30, **kwargs)
 zi = griddata(x,y,z,xi,yi,**kwargs) fits a surface of the form z = f(x,y)
 to the data in the (usually) nonuniformly spaced vectors (x,y,z).
 griddata interpolates this surface at the points specified by (xi,yi)
 to produce zi. 
 xi and yi form a grid (usually produced by meshgrid).
 and must be monotone increasing, but not necessarily uniformly spaced.
 Uses a technique called "natural neighbor interpolation" (see e.g
 Sibson, R., A Brief Description of Natural Neighbor Interpolation,
 in Interpreting Multivariate Data, ed. by V. Barnett,
 John Wiley & Sons, New York, 1981, pp. 21-36) as implemented
 in the NCAR natgrid library (http://ngwww.ucar.edu/ngdoc/ng/ngmath/natgrid/nnhome.html).
 
 Download: http://www.esrl.noaa.gov/psd/people/jeffrey.s.whitaker/python/griddata-0.1.1.tar.gz
 
 Parameters controlling interpolation (set in **kwargs)
 (For more details see
  http://ngwww.ucar.edu/ngdoc/ng/ngmath/natgrid/contents.html)
 
Parameter | parameter  |                     |               |
  name    |   type     |  description        | legal values  | default value
          |            |                     |               |
------------------------------------------------------------------------------
  bI      | float      | tautness factor that| >= 1.         | 1.5
          |            | increases the       |               |
          |            | effect of the       |               |
          |            | gradients as bI     |               |
          |            | increases.          |               |
------------------------------------------------------------------------------
  bJ      | float      | tautness factor that| >= 1.         | 7.0
          |            | decreases the       |               |
          |            | breadth of the      |               |
          |            | region affected by  |               |
          |            | the gradients.      |               |
------------------------------------------------------------------------------
  dup     | int        | controls whether    | 0 = no        | 0
          |            | duplicate input     | 1 = yes       |
          |            | coordinates are     |               |
          |            | allowed.            |               |
------------------------------------------------------------------------------
  ext     | int        | flags whether       | 0 = no        | 1
          |            | extrapolation is    | 1 = yes       |
          |            | allowed outside the |               |
          |            | convex hull.        |               |
------------------------------------------------------------------------------
  hor     | float      | Specifies the       | >= 0.         | 0.1*(extent of
          |            | amount of horizontal|               | X values in
          |            | overlap to be       |               | output grid)
          |            | included outside of |               |             
          |            | the current region. |               |             
------------------------------------------------------------------------------
  igr     | int        | flag indicating if  | 0 = no        | 0
          |            | nonlinear interp    | 1 = yes       |
          |            | is to be done.      |               |
-------------------------------------------------------------------------------
  non     | int        | flags whether in-   | 0 = yes       | 0
          |            | terpolated values   | 1 = no        |
          |            | are allowed to be   |               |
          |            | negative.           |               |
------------------------------------------------------------------------------
  nul     | float      | the value to be used| Any float     | 0.0
          |            | on output for points|               |
          |            | outside of the      |               |
          |            | convex hull when    |               |
          |            | extrapolation is not|               |
          |            | allowed.            |               |
------------------------------------------------------------------------------
  ver     | float      | Specifies the       | >= 0.         | 0.1*(extent of
          |            | amount of vertical  |               | Y values in the
          |            | overlap to be       |               | output grid)
          |            | included outside of |               |            
          |            | the current region. |               |            
------------------------------------------------------------------------------
 
 if masked=True (default False), no extrapolation is done outside the 
 convex hull defined by the data points, and a masked array with a fill value
 given by the 'fill_value' keyword (default 1.e30) is returned.
 Equivalent to setting 'ext=0' and 'nul=fill_value' in **kwargs, and masking
 the output values that are equal to fill_value. 
 Setting masked=True will override the values of ext and nul 
 specified in **kwargs.

 
Data
        __version__ = 0.1.1