D-Piper is a free source code developed in Python 3 that allows to represent large hydrochemical data sets throughout point density diagrams. Multiple methods of data distribution can be chosen for data visualization.

To make a D-Piper diagram just follow these steps:

Keep the file structure as shown in the figure:

• The input analytical data files must be saved in the Data folder. The sample files used in the article to make Figures 2, 3, 4 and 5 can be found in this folder.
• The D-Piper diagrams will be saved in the Graphics folder. It currently contains some example images.
• The file D_Piper_v1_options.txt contains the necessary instructions and explanations to build the desired D-Piper diagram.
• The file D_Piper_v1.py is the script that you have to run in Python to build a D-Piper diagram. The script is widely commented.
• The Tools.py file is an auxiliary Python code that act as a module and contains all the functions with which the D_Piper_v1.py file operates.

Do not delete or change any of the above files or folders. If necessary, you can add other folders or files. Note that automatically a pycache folder is created, requiered for an optimal execution of the program.

The script always reads the drawing options from the D_Piper_v1_options.txt file. If you want to save a set of options, you must do so by renaming the file or saving it to another location. For further use, you will have to name it as the original one (D_Piper_v1_options.txt) or update the new name in line 65 of the D_Piper_v1.py file.

The data file must be in ASCII format and saved in the Data folder. The data file can have any name. The structure of the data file should be as follows:

• TAB-separated ASCII file
• It must contain ten columns:

Identifier: sample identification number.
Group: Each sample can belong to a different group. Up to nine groups can be differentiated. Although no error will be shown, setting more groups will create overlap problems.
Eight columns with analytical results. The ion content should be expressed in mg/L (milligrams per liter) or ppm (parts per million).

The D_Piper_v1_options.txt file must be in ASCII format, separated by semicolon (;) It is a self-explanatory file that shows all the options of the program. It is essential to comply with the file format to avoid execution errors.

The contents of this file are explained at the end of this document. Options that can be modified are shown in red, explanatory text and guidelines are shown in blue, and variable names in black.

All authors belong to IGME Geological Survey of Spain. C/Ríos Rosas 23, 28003 Madrid, Spain

• M. González-Jiménez [email protected]

• L. Moreno Merino [email protected]

• H. Aguilera Alonso [email protected]

• E. Díaz Losada [email protected]

License: GPLv3