Install xca

Compiling xca from source

The TRIQS library, see TRIQS installation instructions.. We are currently depending on the unstable development branch of TRIQS that has to be compiled from source. (Note that the packaged versions of TRIQS are not yet supported.)

In the following, we assume that TRIQS is installed in the directory path_to_triqs.

Download the source code by cloning the TRIQS/xca repository from GitHub:
```
$ git clone https://github.com/TRIQS/xca xca.src
```
Create and move to a new directory where you will compile the code:
```
$ mkdir xca.build && cd xca.build
```
Ensure that your shell contains the TRIQS environment variables by sourcing the triqsvars.sh file from your TRIQS installation:
```
$ source path_to_triqs/share/triqs/triqsvars.sh
```
In the build directory call cmake, including any additional custom CMake options, see below:
```
$ cmake ../xca.src
```
Compile the code, run the tests and install the application:
```
$ make
$ make test
$ make install
```

The compilation of xca can be configured using CMake-options:

cmake ../xca.src -DOPTION1=value1 -DOPTION2=value2 ...

Options	Syntax
Specify an installation path other than path_to_triqs	-DCMAKE_INSTALL_PREFIX=path_to_xca
Build in Debugging Mode	-DCMAKE_BUILD_TYPE=Debug
Disable testing (not recommended)	-DBuild_Tests=OFF
Build the documentation	-DBuild_Documentation=ON
Update the Python bindings (developers only)	-DUpdate_Python_Bindings=ON