cdflib.setVarBlockingFactor

Specify blocking factor for variable

Syntax

cdflib.setVarBlockingFactor(cdfId,varNum,blockingFactor)


Description

cdflib.setVarBlockingFactor(cdfId,varNum,blockingFactor) specifies the blocking factor for a variable in a Common Data Format (CDF) file.

Input Arguments

cdfId	Identifier of a CDF file, returned by a call to cdflib.create or cdflib.open.
varNum	Numeric value identifying a variable in the file. Variable numbers are zero-based.
blockingFactor	Numeric value that specifies the number of records to allocate when writing to an unallocated record.

Examples

Create a CDF, create a variable in the CDF, and then set the blocking factor used with the variable. To run this example, you must be in a writable folder.

cdfId = cdflib.create("your_file.cdf");

% Create a variable in the file
varNum = cdflib.createVar(cdfId,"Time","cdf_int1",1,[],true,[]);

% Get the current blocking factor used with the variable 
bFactor = cdflib.getVarBlockingFactor(cdfId,varNum)

bFactor =

     0

% Change the blocking factor for the variable
cdflib.setVarBlockingFactor(cdfId,varNum,10);

% Check the new blocking factor
bFactor = cdflib.getVarBlockingFactor(cdfId,varNum)

bFactor =

    10

%Clean up
cdflib.delete(cdfId)
clear cdfId

More About

blocking factor

A variable's blocking factor specifies the minimum number of records the library allocates when you write to an unallocated record. If you specify a fractional blocking factor, the library rounds the value down.

Tips

• This function corresponds to the CDF library C API routine CDFsetzVarBlockingFactor.

• To use this function, you must be familiar with the CDF C interface. You can access the CDF documentation at the CDF website.