Log Parts

Log Header

The log header provides an introduction to your log. The header block contains the path of the log file, the working directory, the name of the user, a date-time stamp, and other useful information concerning the operating environment.

Log Body

The log body comprises the primary content of your log. The body will be populated with print-outs from the objects you send to the log with log_print(), put() and sep(). The objects will be printed to the log just as they are printed to the console.

Optional notes will be written to the log for every call to log_print() or put(). The notes will follow the printing of the object, and will include a date-time stamp and the elapsed time since the last call. If the object is of class data.frame the number of rows and columns will also be noted.

Notes can be turned off with the show_notes parameter on log_open(), or by setting the global option logr.notes to FALSE.

Log Footer

The log footer concludes the log with another date-time stamp for the log end time, and a total elapsed time for the entire script.

Note that during batch runs or when sourcing a script, the log footer may not be generated if the script errors. Instead, the last line of the log will be the error message.

Example

Here is an example log showing each of the log parts described above:

========================================================================= 
Log Path: C:/Users/dbosa/AppData/Local/Temp/RtmpQtOzhy/log/test.log 
Working Directory: C:/packages/logr 
User Name: dbosak 
R Version: R Under development (unstable) (2020-06-29 r78751) 
Machine: BOSAK-MAIN x86-64 
Operating System: Windows 10 x64 build 18362 
Base Packages: stats graphics grDevices utils datasets methods base
Other Packages: logr_1.2.7 dplyr_1.0.7 
Log Start Time: 2020-06-30 07:15:52 
========================================================================= 

High Mileage Cars Subset 

NOTE: Log Print Time:  2020-06-30 07:15:52 
NOTE: Elapsed Time in seconds: 0.0219531059265137 

                mpg cyl  disp  hp drat    wt  qsec vs am gear carb
Mazda RX4      21.0   6 160.0 110 3.90 2.620 16.46  0  1    4    4
Mazda RX4 Wag  21.0   6 160.0 110 3.90 2.875 17.02  0  1    4    4
Datsun 710     22.8   4 108.0  93 3.85 2.320 18.61  1  1    4    1
Hornet 4 Drive 21.4   6 258.0 110 3.08 3.215 19.44  1  0    3    1
Merc 240D      24.4   4 146.7  62 3.69 3.190 20.00  1  0    4    2
Merc 230       22.8   4 140.8  95 3.92 3.150 22.90  1  0    4    2
Fiat 128       32.4   4  78.7  66 4.08 2.200 19.47  1  1    4    1
Honda Civic    30.4   4  75.7  52 4.93 1.615 18.52  1  1    4    2
Toyota Corolla 33.9   4  71.1  65 4.22 1.835 19.90  1  1    4    1
Toyota Corona  21.5   4 120.1  97 3.70 2.465 20.01  1  0    3    1
Fiat X1-9      27.3   4  79.0  66 4.08 1.935 18.90  1  1    4    1
Porsche 914-2  26.0   4 120.3  91 4.43 2.140 16.70  0  1    5    2
Lotus Europa   30.4   4  95.1 113 3.77 1.513 16.90  1  1    5    2
Volvo 142E     21.4   4 121.0 109 4.11 2.780 18.60  1  1    4    2

NOTE: Data frame has 14 rows and 11 columns. 

NOTE: Log Print Time:  2020-06-30 07:15:52 
NOTE: Elapsed Time in seconds: 0.0508558750152588 

========================================================================= 
Log End Time: 2020-06-30 07:15:53 
Log Elapsed Time: 0 00:00:00 
========================================================================= 

Next: Additional Features