VTKFortran

Pure Fortran VTK XML API — a pure Fortran 2003+ OOP library for writing and reading files conforming the VTK XML standard.

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Features

• Write Rectilinear, Structured, and Unstructured grids in the VTK XML format
• Composite multi-block datasets (.vtm) and parallel partitioned files (.pvts) supported
• Output formats: ASCII, binary (Base64-encoded), and raw binary appended
• Thread and processor safe — multiple files can be written concurrently under OpenMP or MPI
• OOP design — polymorphic xml_writer allocated at runtime; vtk_file, pvtk_file, vtm_file types expose a clean type-bound-procedure API
• All procedures return an integer error code — zero means success

Documentation | API Reference

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Authors

• Stefano Zaghi — @szaghi

Contributions are welcome — see the Contributing page.

Copyrights

This project is distributed under a multi-licensing system:

• FOSS projects: GPL v3
• Closed source / commercial: BSD 2-Clause, BSD 3-Clause, or MIT

Anyone interested in using, developing, or contributing to this project is welcome — pick the license that best fits your needs.

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Quick start

Write a structured grid in binary XML format:

use vtk_fortran, only : vtk_file
use penf,        only : I4P, R8P
implicit none
type(vtk_file)     :: a_vtk_file
integer, parameter :: nx1=0, nx2=9, ny1=0, ny2=5, nz1=0, nz2=5
integer, parameter :: nn=(nx2-nx1+1)*(ny2-ny1+1)*(nz2-nz1+1)
real(R8P)          :: x(nx1:nx2,ny1:ny2,nz1:nz2)
real(R8P)          :: y(nx1:nx2,ny1:ny2,nz1:nz2)
real(R8P)          :: z(nx1:nx2,ny1:ny2,nz1:nz2)
real(R8P)          :: v(nx1:nx2,ny1:ny2,nz1:nz2)
integer            :: error

error = a_vtk_file%initialize(format='binary', filename='output.vts', &
                              mesh_topology='StructuredGrid',          &
                              nx1=nx1, nx2=nx2, ny1=ny1, ny2=ny2, nz1=nz1, nz2=nz2)
error = a_vtk_file%xml_writer%write_piece(nx1=nx1, nx2=nx2, ny1=ny1, ny2=ny2, nz1=nz1, nz2=nz2)
error = a_vtk_file%xml_writer%write_geo(n=nn, x=x, y=y, z=z)
error = a_vtk_file%xml_writer%write_dataarray(location='node', action='open')
error = a_vtk_file%xml_writer%write_dataarray(data_name='pressure', x=v, one_component=.true.)
error = a_vtk_file%xml_writer%write_dataarray(location='node', action='close')
error = a_vtk_file%xml_writer%write_piece()
error = a_vtk_file%finalize()

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Install

Clone and build with CMake

git clone https://github.com/szaghi/VTKFortran --recursive
cd VTKFortran
cmake -S . -B build -DBUILD_TESTING=ON
cmake --build build && ctest --test-dir build

CMake subdirectory integration

add_subdirectory(VTKFortran)
target_link_libraries(your_target VTKFortran::VTKFortran)

Tool	Command
CMake	cmake -S . -B build && cmake --build build
FoBiS.py	FoBiS.py build -mode static-gnu
FPM	fpm build