Simulates a sensor using an arbitrary expression that can be supplied via a configuration option., The plugin uses the C++ Mathematical Expression Toolkit Library by Arash Partow and is used under the MIT licence granted on that toolkit.
See http://www.partow.net/programming/exprtk/index.html
The plugin only allows single variable expression, with a controlling variable called x that is set between defined minimum and maximum values using a step value. All of these are configured via configuratin parameters.
The ExprTk library has the following capabilities:
- Mathematical operators (+, -, *, /, %, ^)
- Functions (min, max, avg, sum, abs, ceil, floor, round, roundn, exp, log, log10, logn, pow, root, sqrt, clamp, inrange, swap)
- Trigonometry (sin, cos, tan, acos, asin, atan, atan2, cosh, cot, csc, sec, sinh, tanh, d2r, r2d, d2g, g2d, hyp)
To build Fledge Expression C++ South plugin:
$ mkdir build
$ cd build
$ cmake ..
- By default the Fledge develop package header files and libraries are expected to be located in /usr/include/fledge and /usr/lib/fledge
- If FLEDGE_ROOT env var is set and no -D options are set, the header files and libraries paths are pulled from the ones under the FLEDGE_ROOT directory. Please note that you must first run 'make' in the FLEDGE_ROOT directory.
You may also pass one or more of the following options to cmake to override this default behaviour:
- FLEDGE_SRC sets the path of a Fledge source tree
- FLEDGE_INCLUDE sets the path to Fledge header files
- FLEDGE_LIB sets the path to Fledge libraries
- FLEDGE_INSTALL sets the installation path of Expression plugin
- NOTE:
- The FLEDGE_INCLUDE option should point to a location where all the Fledge header files have been installed in a single directory.
- The FLEDGE_LIB option should point to a location where all the Fledge libraries have been installed in a single directory.
- 'make install' target is defined only when FLEDGE_INSTALL is set
Examples:
no options
$ cmake ..
no options and FLEDGE_ROOT set
$ export FLEDGE_ROOT=/some_fledge_setup
$ cmake ..
set FLEDGE_SRC
$ cmake -DFLEDGE_SRC=/home/source/develop/Fledge ..
set FLEDGE_INCLUDE
$ cmake -DFLEDGE_INCLUDE=/dev-package/include ..
set FLEDGE_LIB
$ cmake -DFLEDGE_LIB=/home/dev/package/lib ..
set FLEDGE_INSTALL
$ cmake -DFLEDGE_INSTALL=/home/source/develop/Fledge ..
$ cmake -DFLEDGE_INSTALL=/usr/local/fledge ..