getnext - Get next value from ValueIterator - MATLAB (original) (raw)
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Get next value from ValueIterator
Syntax
Description
X = getnext([ValIter](#buhb1zd-ValIter))
returns the next available value in ValIter
. Use the hasnext
function to confirm availability of values in ValIter
before calling getnext
.
Examples
Use the hasnext
and getnext
functions in a while
loop within the reduce function to iteratively get values from the ValueIterator
object. For example,
function MeanDistReduceFun(sumLenKey, sumLenIter, outKVStore) sumLen = [0 0]; while hasnext(sumLenIter) sumLen = sumLen + getnext(sumLenIter); end add(outKVStore, 'Mean', sumLen(1)/sumLen(2)); end
Always call hasnext
before getnext
to confirm availability of a value. mapreduce
returns an error if you call getnext
with no remaining values in the ValueIterator
object.
Input Arguments
Intermediate value iterator, specified as a ValueIterator
object. The mapreduce
function automatically creates this object during execution. The second input to the reduce function specifies the variable name for the ValueIterator
object, which is the variable name to use with the hasnext
and getnext
functions.
For more information, see ValueIterator.
Version History
Introduced in R2014b