When you first start up your application and initialize the buffers the buffers will be available until you end your program, then the memory space the buffer uses will be dropped.
As your program is running and data is being stored to the memory buffers, before the buffer is completely full you will need to transfer the data points to your application. If you do not then the data points that you had not transferred will be lost. You can transfer the data points using a couple different methods such as ps3000_get_streaming_last_values or ps3000_get_streaming_values_no_aggregation. This does not clear/delete the buffer, but transfers them to your application before they are overwritten.
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