CSSRlib-data

Sample scripts and datasets for CSSRlib. The scripts require an installation of the CSSRlib package.

Prerequisites:

Pre-installation of CSSRlib is required. Install the officially released package with pip using

pip install cssrlib

It is recommended to use a virtual environment to avoid version conflicts of required modules with the system-wide python installation.

Installation in Virtual Environment

Create a virtual environment cssrlib-venv in the current directory with

python3 -m venv cssrlib-venv

Activate the environment with

source cssrlib-venv/bin/activate

To make the base CSSRlib module available in the virtual environment, there are several options:

1. Install the official package

Install the officially released package with pip

pip install cssrlib

This will be sufficient for most cases, but typically the version from the github repository is more up-to-date.

2. Install from github repository

Install cssrlib from the main branch of the github repository with this command

pip install -U git+https://github.com/hirokawa/cssrlib.git@main

If you like to use the development branch with the most recent changes, substitute @mainwith @devel.

IMPORTANT: make sure to always use consistent branches for cssrlib and cssrlib-data!

3. Install a local copy of the github repository

For this installation guide, it is assumed that the CSSRlib base repository has been cloned to a folder cssrlib in the same directory as the samples repository cssrlib-data. The command ls | grep cssrlib should then return

cssrlib
cssrlib-data
cssrlib-venv

Install the local module in editing mode using the -e flag:

pip install -e ./cssrlib

4. Make a local copy available without installation

NOTE: this is not necessary if the cssrlib package has been installed with pip through one of the steps above!

Make sure the path to the src folder of the cssrlib base repository appears in the python path.

echo $PYTHONPATH

If not, add it with the following export command, where <path-to-cssrlib> must be replaced with the full path to CSSRlib base repository.

export PYTHONPATH="$PYTHONPATH:<path-to-cssrlib>/src"

Check CSSRlib base package installation

Check if the package inclusion works with

python -c "import cssrlib; print(cssrlib.__version__); print(cssrlib.__file__)"

If the cssrlib package was installed with pip, you can display the installation details with

pip show cssrlib

Install dependencies for data repository

Install the dependencies from the requirements.txt file of cssrlib-data:

pip install -r cssrlib-data/requirements.txt

Data download from IGS

Most sample scripts require IGS data for processing. The data can be downloaded with a script, which must be called before the scripts can be executed:

cd ./cssrlib-data/samples
python3 igs_download.py

Handling Warnings from the PySolid module

The module pysolid is used for the computation of solid Earth tides. It contains a hard-coded leap second table with an expiration date, which is set to the next possible injection date of a leap second at the time of the last update. The table is frequently updated by the package maintainers. The following warning is issued when the expiration date is exceeded:

Mild Warning -- time crossed leap second table boundaries. Boundary edge value used instead

If you encounter this warning when executing CSSRlib scripts, it can most likely be removed by updating pysolid to the most recent version using

pip install --upgrade pysolid

If the warnings persist, installing the latest version from the repository can help

pip install -U git+https://github.com/insarlab/PySolid.git@main

Ephemeris: RINEX/TLE

• test_eph.py reading/plotting ephemeris from RINEX 3
• test_tlesim.py reading/plotting TLE orbit

Model

• test_trop.py tropospheric delay model
• cacode.py GPS/QZSS C/A code simulation

Positioning: Static

• test_pntpos.py Standalone positioning
• test_rtk.py RTK positioning
• test_ppprtk.py PPP-RTK positioning

Positioning: Kinematic

• test_pntpos2.py Standalone positioning
• test_rtk2.py RTK positioning
• test_ppprtk2.py PPP-RTK positioning

ToDo-List

• Implement pole tide displacements
• Check and improve observation noise settings
• Add residual output
• Add check for observations, first two observations must be on different frequencies
• Number of frequencies nav.nf should be set automatically depending on specified signals