Reads a section of a time trace from a HistoryBase ring buffer.
Syntax
RingBufferReadTime(HistoryBaseFile, Machine, FromTime, ToTime, [ CalendarTime = TRUE ] [ , SubRate = 1 ])
The syntax of the RingBufferReadTime function consists of the following parts:
Part |
Description |
|---|---|
HistoryBaseFile |
String with the path of the ring buffer file to be read. Permitted data structures are Scalar value. Supported data types are String (file name). |
Machine |
Name of a computer in the network on which the specified ring buffer file is already being used by a HistoryBase component. This argument can also be an empty text. In this case, the HistoryBase instance is searched for or instantiated on the executing system. Permitted data structures are Scalar value. Supported data types are String. |
FromTime |
The date and time of the first (oldest) time value to be read. Permitted data structures are Scalar value. Supported data types are 32-bit integer, 64-bit floating point und Calendar time. |
ToTime |
The date and time of the last (most recent) time value to be read. This date and time must be greater than the date and time specified in FromTime. Permitted data structures are Scalar value. Supported data types are 32-bit integer, 64-bit floating point und Calendar time. |
CalendarTime |
Boolean value specifying that the time data are to be read as calendar times. Otherwise, the time is provided in seconds where FromTime corresponds to zero. Permitted data structures are Scalar value. Supported data types are Boolean value. If this argument is omitted, it will be set to the default value TRUE . |
SubRate |
Integer value which specifies the sub-rate. Time is reduced according to the given sub-rate to return the time values for a trace belonging to a group having a sub-rate. This parameter is evaluated only when working with HistoryBase 3 or higher. Permitted data structures are Scalar value. All integral data types are permitted. The value must be greater or equal to 1. If this argument is omitted, it will be set to the default value 1 . |
Remarks
The result always has the data structure Data series.
Weisang HistoryBase version 2.4 or higher must be installed on the executing system and, if applicable, on the system specified in Machine. The result is provided in UTC time format.
If an argument is a list, then the first element in the list is taken. If this is also a list, then the process is repeated.
Available in
FlexPro View, Basic, Professional, Developer Suite
Examples
RingBufferReadTime("C:\RingBuffer.rbf", "RemoteMachine", '1.1.2010 10:00', '1.1.2010 11:00') |