Dsgrid Error handling

The error handling functions

Dsgrid contains a set of procedures that implement a centralized error handling capability. The package invokes the C function DSErrorHnd to produce all of its error messages. DSErrorHnd simply invokes the DSErrorLog function with the same arguments as DSErrorHnd. This allows a user to replace the error handling functionality by replacing or modifying the DSErrorHnd function with one that handles errors in an application-dependent manner. All of the error handling functions are written in C; there is no way to replace the error handler using Fortran code.

Detailed description of the error functions:

The error functions are:

DSErrorHnd - primary error handler
DSErrorLog - error logger
DSErrMsg - retrieves error messages
DSErrMax - retrieves the number of possible error messages

DSErrorHnd - Primary error handler

DSErrorHnd simply invokes the DSErrorLog function with the arguments specified in DSErrorHnd. This allows a user to replace the error handling functionality by replacing or modifying the DSErrorHnd function with one that handles errors in an application-dependent manner.

Function prototype:

  void DSErrorHnd (int, char *, FILE *, char *);

Argument description:

-----------------------------------
                Argument | Type   
-----------------------------------
void DSErrorHnd (error,  | int    
                 func,   | char * 
                 efile,  | FILE * 
                 smsg);  | char * 
-----------------------------------

error: The error number, as described in the error table.
func: A string specifying the function that is invoking the error call.
efile: Specifies the file where the error message will be written. By default error messages are written to stderr.
smsg: The error message; this will usually be DSErrMsg(i) where i is an error number.

DSErrorLog - error logger

Function prototype:

  void DSErrorLog (int, char *, FILE *, char *);

Argument description:

----------------------------------
                Argument | Type   
----------------------------------
void DSErrorLog (error,  | int    
                 func,   | char * 
                 efile,  | FILE * 
                 smsg);  | char * 
----------------------------------

error: The error number, as described in the error table.
func: A string specifying the function that is invoking the error call.
efile: Specifies the file where the error message will be written. By default error messages are written to stderr.
smsg: The error message; this will usually be DSErrMsg(i) where i is an error number.

DSErrMsg - retrieves error messages

Function prototype:

  char *DSErrMsg(int i)

Return value:

DSErrMsg returns the error message associated with its integer argument.

Argument description:

-------------------------------------
                    Argument | Type  
-------------------------------------
char *DSErrMsg (error_num    | int
                         );  | 
-------------------------------------

error_num: An error number.

DSErrMax - retrieves the number of possible error messages

Function prototype:

   int DSErrMax()

Return value:

The value returned is the total number of possible error messages.

Error table

The following table lists all of the error numbers and the associated error messages:

----------------------------------------------------------------------------
 Error  |                     Error message
 number |    
----------------------------------------------------------------------------
    1   |  Error number out of range.
    2   |  Insufficient data in gridded region to triangulate.
    3   |  Array dimension out of range.
    4   |  Parameter name not known.
    5   |  Cannot open error file.
    6   |  Error allocating memory for input points.
    7   |  Fortran DOUBLE PRECISION entries are not supported on UNICOS.
    9   |  Error allocating memory for array of distances between input points.
   10   |  Error allocating memory for weights.
   11   |  Error allocating memory for distance ordering vector.
   12   |  Error allocating memory for output array.
   13   |  Number of input points must be greater than 2.
   14   |  No original data values within the specified distance -
        |     interpolated value set to missing value flag.
----------------------------------------------------------------------------