Looking for information on sinking mismatched time series

Hi, I'm struggleing to phase a question so I can search the help file. I have two instruments producing 1 second data and I want to compare the out put directly, but as with all instrumentation, ocationaly, one instrument will drop a second so the two outputs are slightly mismatched in places. I am looking for a command whcih will allow me to create one time stamp with 2 columns of data with blanks where no data is available.

Example

data I have

data stream 1,,data stream 2,

17:31:01,333,17:31:01,332

17:31:02,345,17:31:02,344

17:31:04,321,17:31:03,326

17:31:05,365,17:31:05,363

17:31:06,352,17:31:06,358

17:31:07,389,17:31:08,381

data I want

Time,instrument1,instrument 2,

17:31:01,333,332,

17:31:02,345,344,

17:31:03,,326,

17:31:04,321,,

17:31:05,365,363,

17:31:06,352,358,

17:31:07,389,,

17:31:08,,381,

I'm not realy sure what to call this type of operation or if in fact matlab already has a command for this. I just feel like there should be one! Any help greatfully received.

Karen

Answer 1

[Walter Roberson]

unique() the two sets of timestamps together in the same array, to get the joint list of timestamps.

ismember() the first set of timestamps against the joint list. The locations not matched will require NaN for the first series.

ismember() the second set of timestamps against the joint list. The locations not matched will require NaN for the second series.

Answer 2

[Sean de Wolski]

Fill those points with Nan.

doc nan

[Karen Hornsby]

I realize I will need to add nans to the output, but I want to know how to generate the single time stamp and then sample the data into a single matrix.