Export information from the Trend history
file(s) in proprietary binary format ( *.hst ) to a plain text ( *.txt) or comma-delimited ( *csv ) file.
|
Function |
Group |
Execution |
Windows |
Embedded |
Thin Client |
| HST2TXT
|
File |
Asynchronous |
Supported |
Supported |
Supported |
Syntax
HST2TXT( strStartDate, strStartTime, numDuration, numGroup, strTargetFile, optStrSeparator, optNumMilliseconds, optStrFormat, optNumInterval )
- strStartDate
- The start date of the data.
- strStartTime
- The start time of the data.
- numDuration
- Numerical tag containing duration of the data in
hours.
- numGroup
- Numerical tag containing trend group number.
- strTargetFile
- String tag containing path and name of the file to
be written.
- optStrSeparator
- Optional The data separator
character for file. If omitted, the function uses the TAB character
(\t) to separate the values in the text file.
- optNumMilliseconds
- Optional numeric tag. If this
parameter is false (0), the text
file created will not show milisecond-precision on the timestamp of
each history sample.
- optStrFormat
- String tag, which specifies the order of the Month
(M), Day (D), and Year (Y) for the time-stamp format exported to
the text file:
- "DMY": Day, Month, Year
- "MDY": Month, Day, Year
- "YMD": Year, Month, Day
If omitted, the function uses the format DMY for the
timestamp in the text file.
- optNumInterval
- Optional numeric tag
specifying the sampling interval. Only line itmes at this interval
are written as text to the target file; all other line items in the
Trend history are discarded.
For example, if optNumInterval has a value of 10, then only
every tenth line item is written out.
Returned value
| −3 |
Invalid
number of parameters |
| −2 |
Dll
functions not found |
| −1 |
InStudiot.dll not found |
| 0 |
Function
was executed successfully |
| 1 |
Error.
Previous execution of the HST2TXT
has not yet been completed |
Examples
|
Tag Name |
Expression |
|
Tag |
HST2TXT( "04/14/2002", "06:30:00", 0.1, 3,
"C:\Studio\data.txt", "\" )
|
|
Tag |
HST2TXT( "04/14/2002", "06:30:00", 0.1, 3,
"C:\Studio\data.csv", "," , "MDY" )
|
|
Tag |
HST2TXT( "04/14/2002", "06:30:00", 0.1, 3,
"C:\Studio\data.csv", "," , "MDY", 10 )
|
Tip: When using
the comma character (,) as optStrSeparator, the function creates a file in
the CSV format (Comma Separated Values). It is a useful tool for
exporting the Trend history data from the proprietary binary format
into a file that can be opened with Microsoft Excel.