quanser.communications.stream.send_single_array

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Sends an array of 32-bit floating-point numbers as an atomic unit over a stream.

Syntax

[is_sent, would_block] = stream.send_single_array(values)

Description

This function writes data to the stream buffer. It attempts to store the values array in the stream buffer as an array of 32-bit real numbers. It differs from the send_singles function in that it treats the entire array as an atomic unit. It either writes all of the array or none of it. If there is enough room available in the stream buffer then it stores the data in the buffer and returns immediately. The data is not written to the actual communication channel until the stream is flushed using flush or there is no more room available in the stream buffer. If an error occurs, then it issues an error message. If the connection is closed it is considered an error condition.

If quanser.communications.stream.listen or quanser.communications.stream.connect was called with the non-blocking flag set to false (0), then this function may block attempting to flush the stream buffer. All the data will be consumed and the total number of elements sent is returned. Some of the data may remain in the stream buffer and not be sent until the next time flush is called or there is no more room available in the stream buffer. If an error occurs then an error is issued and the stream should be closed.

If quanser.communications.stream.listen or quanser.communications.stream.connect was called with the non-blocking flag set to true (1), then this function does not block. It returns 1 if the array is sent successfully. If no elements could be sent without blocking, then is_sent is 0 and would_block is set to true (1). If an error occurs then an error is issued and the stream should be closed.

This operation is not valid on listening streams created using quanser.communications.stream.listen.

Parameters

stream

Stream handle returned by quanser.communications.stream.connect or accept.

values

The values to send. Any numeric datatype may be used but each array element will be cast to a single prior to writing the data to the stream.

Outputs

is_sent

Set to true (1) if the array is written to the stream buffer, and zero otherwise. For blocking streams, a value of 0 is returned only if the values array is empty.

would_block

Whether the function would have blocked. Always false for blocking streams.

Examples

values = [3.14, -2.818, 32.5, 9.2];
is_sent = stream.send_single_array(values);    % Send four 32-bit real numbers