CounterMultiChannelReader.EndMemoryOptimizedReadMultiSampleDouble Method
- Updated2023-02-21
- 2 minute(s) read
CounterMultiChannelReaderEndMemoryOptimizedReadMultiSampleDouble Method
Handles the end of an asynchronous read initiated with
BeginMemoryOptimizedReadMultiSampleDouble(Int32, AsyncCallback, Object, Double)
and retrieves the read samples.
Namespace: NationalInstruments.DAQmx
Assembly: NationalInstruments.DAQmx (in NationalInstruments.DAQmx.dll) Version: 20.7.40.49302
Syntax
public double[,] EndMemoryOptimizedReadMultiSampleDouble( IAsyncResult asyncResult, out int actualNumberOfSamplesPerChannelRead )
Public Function EndMemoryOptimizedReadMultiSampleDouble ( asyncResult As IAsyncResult, <OutAttribute> ByRef actualNumberOfSamplesPerChannelRead As Integer ) As Double(,)
Parameters
- asyncResult
- Type: SystemIAsyncResult
An IAsyncResult that represents an asynchronous call started by calling BeginMemoryOptimizedReadMultiSampleDouble(Int32, AsyncCallback, Object, Double). - actualNumberOfSamplesPerChannelRead
- Type: SystemInt32
The actual number of samples per channel read. This is useful when the reading operation yields fewer samples than the actual length of data.
Return Value
Type: DoubleA 2D array of Double samples that contains the read data. Each element in the first dimension of the array corresponds to a channel in the task. Each element in the second dimension of the array corresponds to a sample from each of the channels. The order of the channels in the array corresponds to the order in which you add the channels to the task or to the order of the channels you specify in ChannelsToRead.
Exceptions
| Exception | Condition |
|---|---|
| ArgumentException |
|
| DaqException | The NI-DAQmx driver returned an error during the asynchronous operation. |
| OutOfMemoryException | There is not enough memory to carry out this operation. |
Remarks
If you call this method before the asynchronous read IAsyncResult is complete, it waits for the read to complete before returning.
NI-DAQmx scales the returned data to the units of the measurement, including any custom scaling you apply to the channel. You specify these units with the create channel methods or the DAQ Assistant.
NI-DAQmx read and write methods time out after the amount of time specified by the Timeout property on the task you are reading from or writing to.
 Note |
|---|
| Refer to Asynchronous Reads and Writes for additional information. |