pyevtk

library1.7.0pypypi✓ verified 87d ago

pyevtk is a Python library for exporting numerical data (like structured grids, unstructured grids, and points) into binary VTK (Visualization Toolkit) files, enabling visualization in tools like ParaView or VisIt. As of version 1.6.0, it supports various data types and has an active, albeit slow, release cadence.

data

pip install pyevtk

github ↗package ↗

INSTALL

IMPORT

SIG · PYEVTK

pyevtk

datapythonv1.7.0

Install

3.5s avg

Import

269ms

Disk

89MB

Pass rate

10/ 10

Env Coverage10 / 10

glibc

3.9–3.13

musl

3.9–3.13

Install & Compatibility

Where this runs

tested against v1.7.0 · pip install

no network on importno background threads

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

py 3.10–3.910 runs

installs and imports cleanly · install 0.0s · import 0.258s · 89.5MB

glibc

py 3.10–3.910 runs

installs and imports cleanly · install 3.5s · import 0.280s · 86MB

89MB installed

● package 89MB

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

gridToVTK

✓ from pyevtk.hl import gridToVTK

✗ from evtk.hl import gridToVTK

The `evtk` package is an alias for `pyevtk` for backward compatibility but is deprecated and will issue a warning. Always use `pyevtk`.

pointsToVTK

✓ from pyevtk.hl import pointsToVTK

imageToVTK

✓ from pyevtk.hl import imageToVTK

This quickstart demonstrates how to export a structured grid with both cell-centered and point-centered data to a VTK Structured Grid (.vts) file using `gridToVTK`.

import numpy as np from pyevtk.hl import gridToVTK # Define grid dimensions nx, ny, nz = 64, 64, 64 # Coordinates x = np.arange(0, nx, 1, dtype='float64') y = np.arange(0, ny, 1, dtype='float64') z = np.arange(0, nz, 1, dtype='float64') # Cell data (e.g., temperature) temp = np.random.rand(nx - 1, ny - 1, nz - 1) # Point data (e.g., pressure) press = np.random.rand(nx, ny, nz) # Export to VTK file gridToVTK( "output_grid", x, y, z, cellData={'temperature': temp}, pointData={'pressure': press} ) print("VTK file 'output_grid.vts' generated successfully.")

Debug

Known issues

deprecatedUsing `from evtk.hl import ...` is deprecated. The `evtk` package is an alias for `pyevtk` for backward compatibility but will issue a `DeprecationWarning` and may be removed in future versions.

fix

Always use `from pyevtk.hl import ...` for all imports, e.g., `from pyevtk.hl import gridToVTK`.

affects: >=1.1.2

gotchaAll input data arrays (e.g., `data`, `x`, `y`, `z` coordinates) must be NumPy arrays. Passing standard Python lists or other array-like objects will result in `TypeError` or unexpected behavior.

fix

Ensure all array inputs are `numpy.ndarray` objects. Convert them using `numpy.asarray()` if necessary.

affects: All versions

gotchaVTK files generated by `pyevtk` often assume cell-centered data for structured grids. Misinterpreting this can lead to data being shifted by half a cell when visualized in tools like ParaView if your data is node-centered.

fix

Be mindful of whether your data is node-centered or cell-centered. If your data is node-centered on an `(Nx, Ny, Nz)` grid, the data array passed to `gridToVTK` for cell data should typically have dimensions `(Nx-1, Ny-1, Nz-1)` to align correctly. Alternatively, explicitly define point data if appropriate.

affects: All versions

Errors

Common errors & fixes

ModuleNotFoundError: No module named 'evtk'

Attempting to import from the deprecated `evtk` package, which might not be installed or available as an alias in the current environment/version.

fix

Change all imports from `evtk` to `pyevtk`, e.g., `from pyevtk.hl import gridToVTK`.

TypeError: Expected a numpy array for 'data' but got <class 'list'>

Input data (e.g., field values, coordinate arrays) was provided as a Python list or non-NumPy array.

fix

Convert the input data to a NumPy array before passing it to `pyevtk` functions, e.g., `import numpy as np; data = np.asarray(my_list)`.

ValueError: Data dimensions do not match grid dimensions.

The shape of the data array (e.g., `cellData` or `pointData`) does not correspond to the dimensions of the grid (e.g., `(nx, ny, nz)` for structured grids).

fix

Carefully check the expected dimensions for the specific VTK export function being used. For cell data on an `(nx, ny, nz)` grid, the data array should typically have shape `(nx-1, ny-1, nz-1)`. For point data, it should be `(nx, ny, nz)`.

Upgrade

Version history

1.7.0latest on PyPI · released May 28, 2026

Audit

Dependencies

No dependency data recorded yet.

Agent activity

7 hits · last 30 days

node

Resources

githubhttps://github.com/pyscience-projects/pyevtk ↗

packagehttps://pypi.org/project/pyevtk/ ↗