# lgmath

**Repository Path**: neophack/lgmath

## Basic Information

- **Project Name**: lgmath
- **Description**: No description available
- **Primary Language**: Unknown
- **License**: BSD-3-Clause
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2021-05-08
- **Last Updated**: 2021-05-08

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# lgmath
lgmath is a C++ library for handling geometry in state estimation problems in robotics.
It is used to store, manipulate, and apply three-dimensional rotations and transformations and their associated uncertainties.

There are no minimal, constraint-free, singularity-free representations for these quantities,
  so lgmath exploits two different representations for the nominal and noisy parts of the uncertain random variable.
- Nominal rotations and transformations are represented using their composable, singularity-free *matrix Lie groups*, *SO(3)* and *SE(3)*.
- Their uncertainties are represented as multiplicative perturbations on the minimal, constraint-free vectorspaces of their *Lie algebras*, ***so****(3)* and ***se****(3)*.

This library uses concepts and mathematics described in Timothy D. Barfoot's upcoming book [State Estimation for Robotics](asrl.utias.utoronto.ca/~tdb/bib/barfoot_ser15.pdf).
It is used for robotics research at the Autonomous Space Robotics Lab;
  most notably in the STEAM Engine, a library for Simultaneous Trajectory Estimation and Mapping.

# Getting Started
You will need:
- A compiler with C++11 support
- Eigen, at least 3.2.5
- CMake (and optionally catkin) build systems

## Dependencies

### Eigen
In a folder for 3rd party dependencies,
```bash
wget http://bitbucket.org/eigen/eigen/get/3.2.5.tar.gz
tar zxvf 3.2.5.tar.gz
cd eigen-eigen-bdd17ee3b1b3/
mkdir build && cd build
cmake ..
sudo make install
```

## Build
In your development folder
```bash
mkdir lgmath-ws && cd $_
git clone --recursive https://github.com/utiasASRL/lgmath.git
```

Using [catkin](https://github.com/ros/catkin)
and [catkin tools](https://github.com/catkin/catkin_tools) (recommended)
```bash
cd deps/catkin && catkin build
cd ../.. && catkin build
```

Using CMake (manual)
```bash
cd .. && mkdir -p build/catkin_optional && cd $_
cmake ../../lgmath/deps/catkin/catkin_optional && make
cd ../.. && mkdir -p build/catch && cd $_
cmake ../../lgmath/deps/catkin/catch && make cd ../.. && mkdir -p build/lgmath && cd $_
cmake ../../lgmath && make -j4
```

## Install (optional)

Since the catkin build produces a catkin workspace you can overlay, and the CMake build exports
packageConfig.cmake files, it is unnecessary to install lgmath except in production environments. If
you are really sure you need to install, you can use the following procedure.

Using catkin tools (recommended) 
```bash 
cd lgmath 
catkin profile add --copy-active install 
catkin profile set install 
catkin config --install 
catkin build
```

Using CMake (manual)
```bash 
cd build/lgmath 
sudo make install
```

## Uninstall (Optional)

If you have installed, and would like to uninstall,

Using catkin tools (recommended) 
```bash 
cd lgmath && catkin clean -i
```

Using CMake (manual)
```bash
cd build/lgmath && sudo make uninstall
```

## Generating Documentation

Using catkin tool (recommended)
In your catkin workspace
```bash
catkin build --make-arg doc
```


Using CMake (manual)
In your build folder
```bash
make doc
```

The documentation will be found in the `doc` subdirectory of the build folder.