The function is designed to merge time-series data obtained through repeated downloads in the same location. Within a specific locality, the function performs the merging based on 1) logger type, physical element, and sensor height, or 2) based on the list of logger serial numbers to be joined, provided by user in locality metadata.
mc_join(data, comp_sensors = NULL, by_type = TRUE, tolerance = NULL)myClim object in Raw-format. see myClim-package
senors for compare and select source logger; If NULL then first is used. (default NULL)
if TRUE loggers are joined by logger type, height and physical element
if FALSE loggers are joined by logger serial_number see mc_LoggerMetadata (default TRUE)
list of tolerance values for each physical unit see mc_data_physical. e.g. list(T_C = 0.5). Values from older time-series are used for overlaps below tolerance.
myClim object with joined loggers.
Joining is restricted to the myClim Raw-format (refer to myClim-package).
Loggers need to be organized within localities. The simplest method is to use mc_read_data,
providing files_table with locality IDs. When using mc_read_files
without metadata, a bit more coding is needed. In this case, you can create
multiple myClim objects and specify correct locality names afterwards,
then merge these objects using mc_prep_merge, which groups loggers
based on identical locality names.
The joining function operates seamlessly without user intervention in two scenarios:
when the start of a newer time series aligns with the end of an older one, and
when the two time-series share identical values during the overlap.
However, if values differ during the overlap, the user is prompted to interactively choose which time-series to retain and which to discard. myClim provides information about differing time-series in the console, including locality ID, problematic interval (start-end), older logger ID and its time series start-end, and newer logger ID and its time series start-end. Additionally, an interactive graphical window (plotly) displays conflicting time series, allowing the user to zoom in and explore values. In case of multiple conflicts, myClim sequentially asks the user for decisions.
Users have seven options for handling overlap conflicts, six of which are pre-defined. The seventh option allows the user to specify the exact time to trim the older time-series and use the newer one. The options include:
1: using the older logger (to resolve this conflict),
2: using the newer logger (to resolve this conflict),
3: skip this join (same type loggers in locality aren't joined),
4: always using the older logger (to resolve this and all other conflicts),
5: always using the newer logger (to resolve this and all other conflicts)
6: exit joining process.
Users must press the number key, hit Return/Enter,
or write in console the exact date in the format YYYY-MM-DD hh:mm
to trim the older series and continue with the newer series.
by_type = TRUE (default) Loggers are joined based on logger type, physical element, and sensor height. This is a good option for the localities, were are NOT more loggers of identical type and height recording simultaneously.
by_type = FALSE Loggers are joined based on the list of logger_serial belonging to each locality. User must specify in locality metadata, which logger serials are joined together. This is a good option for the localities, with more loggers of identical type and height measuring simultaneously.
Loggers with multiple sensors are joined based on one or more selected sensors (see parameter comp_sensors). The name of the resulting joined sensor is taken from the logger with the oldest data. If serial_number is not equal during logger joining, the resulting serial_number is NA. Clean info is changed to NA except for the step. When joining a non-calibrated sensor with a calibrated one, the calibration information must be empty in the non-calibrated sensor.
The tolerance parameter can be used for cases, when joining multiple
time-series which is "almost" identical, and the difference is caused
e.g. by logger precision or resolution.
For example of joining see myClim vignette.