hasdata - Determine if data is available to read - MATLAB (original) (raw)

Main Content

Determine if data is available to read

Syntax

Description

tf = hasdata([ds](#bueftqx-1-ds)) returns logical1 (true) if there is data available to read from the datastore specified by ds. Otherwise, it returns logical 0 (false).

example

Examples

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Create a datastore from the sample file, mapredout.mat, which is the output file of the mapreduce function.

ds = datastore('mapredout.mat');

While there is data available in the datastore, read the data.

while hasdata(ds) T = read(ds); end

Input Arguments

Extended Capabilities

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Usage notes and limitations:

• In a thread-based environment, you can use hasdata only with the following datastores:
  • ImageDatastore objects
  • CombinedDatastore, SequentialDatastore, orTransformedDatastore objects you create fromImageDatastore objects by usingcombine or transform
    You can use hasdata with other datastores if you have Parallel Computing Toolbox™. To do so, run the function using a process-backed parallel pool instead of using backgroundPool or ThreadPool (use eitherProcessPool or ClusterPool).

For more information, see Run MATLAB Functions in Thread-Based Environment.

Version History

Introduced in R2014b