# Basic usage#

This section demonstrates how to use PyVista to reading and plotting 3D data using the pyvista.examples module and external files.

Tip

This section of the tutorial was adopted from the Basic API Usage chapter of the PyVista documentation.

## Using Existing Data#

There are two main ways of getting data into PyVista: creating it yourself from scratch or loading the dataset from any one of the compatible file formats. Since we’re just starting out, let’s load a file.

If you have a dataset handy, like a surface model, point cloud, or VTK file, you can use that. If you don’t have something immediately available, PyVista has a variety of files you can download in its pyvista.examples.downloads module.

from pyvista import examples
dataset

PolyDataInformation
N Cells5131
N Points2669
N Strips0
X Bounds-2.001e+01, 2.000e+01
Y Bounds-6.480e-01, 4.024e+01
Z Bounds-6.093e-01, 1.513e+01
N Arrays0

Note how this is a pyvista.PolyData, which is effectively a surface dataset containing points, lines, and/or faces. We can immediately plot this with:

dataset.plot(color='tan')


This is a fairly basic plot. You can change how its plotted by adding parameters as show_edges=True or changing the color by setting color to a different value. All of this is described in PyVista’s API documentation in pyvista.plot(), but for now let’s take a look at another dataset. This one is a volumetric dataset.

dataset = examples.download_frog()
dataset

UniformGridInformation
N Cells31594185
N Points31960000
X Bounds0.000e+00, 4.990e+02
Y Bounds0.000e+00, 4.690e+02
Z Bounds0.000e+00, 2.025e+02
Dimensions500, 470, 136
Spacing1.000e+00, 1.000e+00, 1.500e+00
N Arrays1
NameFieldTypeN CompMinMax
MetaImagePointsuint810.000e+002.540e+02

This is a pyvista.UniformGrid, which is a dataset containing a uniform set of points with consistent spacing. When we plot this dataset, we have the option of enabling volumetric plotting, which plots individual cells based on the content of the data associated with those cells.

dataset.plot(volume=True)