This section is only a reference describing the function, please see the chapter on mlab：用Python脚本进行3D绘图 for an introduction to mlab and how to interact with and assemble the functions of mlab.

Please see the section on 运行mlab脚本 for instructions on running the examples.

# Plotting functions¶

## barchart¶

mayavi.mlab.barchart(*args, **kwargs)

Plots vertical glyphs (like bars) scaled vertical, to do histogram-like plots.

This functions accepts a wide variety of inputs, with positions given in 2-D or in 3-D.

Function signatures:

```barchart(s, ...)
barchart(x, y, s, ...)
barchart(x, y, f, ...)
barchart(x, y, z, s, ...)
barchart(x, y, z, f, ...)
```

If only one positional argument is passed, it can be a 1-D, 2-D, or 3-D array giving the length of the vectors. The positions of the data points are deducted from the indices of array, and an uniformly-spaced data set is created.

If 3 positional arguments (x, y, s) are passed the last one must be an array s, or a callable, f, that returns an array. x and y give the 2D coordinates of positions corresponding to the s values.

If 4 positional arguments (x, y, z, s) are passed, the 3 first are arrays giving the 3D coordinates of the data points, and the last one is an array s, or a callable, f, that returns an array giving the data value.

auto_scale

whether to compute automatically the lateral scaling of the glyphs. This might be computationally expensive. Must be a boolean. Default: True

color 颜色

colormap 配色表

extent 可视化范围

figure 图像参数

Figure to populate.

lateral_scale

The lateral scale of the glyph, in units of the distance between nearest points Must be a float. Default: 0.9

line_width 线宽设置

mask_points

If supplied, only one out of ‘mask_points’ data point is displayed. This option is useful to reduce the number of points displayed on large datasets Must be an integer or None.

mode

The glyph used to represent the bars. Must be ‘2dcircle’ or ‘2dcross’ or ‘2ddiamond’ or ‘2dsquare’ or ‘2dthick_cross’ or ‘2dtriangle’ or ‘2dvertex’ or ‘cube’. Default: cube

name 对象命名

opacity 透明度设置

reset_zoom

Reset the zoom to accomodate the data newly added to the scene. Defaults to True.

resolution

The resolution of the glyph created. For spheres, for instance, this is the number of divisions along theta and phi. Must be an integer. Default: 8

scale_factor

the scaling applied to the glyphs. The size of the glyph is by default in drawing units. Must be a float. Default: 1.0

scale_mode

the scaling mode for the glyphs (‘vector’, ‘scalar’, or ‘none’).

transparent

make the opacity of the actor depend on the scalar.

vmax 可视化范围（上界）

vmax将设定图像的配色区间，将图像对应vmax值的部分设定成配色表中的上界颜色。

vmin 可视化范围，下界设置

vmin将设定图像的配色区间，将图像对应vmin值的部分设定成配色表中的下界颜色。如果不设置，默认使用数据中值域下界作为vmin。

Example (run in `ipython --gui=qt`, or in the mayavi2 interactive shell, see 运行mlab脚本 for more info):

```import numpy
from mayavi.mlab import *

def test_barchart():
""" Demo the bar chart plot with a 2D array.
"""
s = np.abs(np.random.random((3, 3)))
return barchart(s)
```

## contour3d¶

mayavi.mlab.contour3d(*args, **kwargs)

Plots iso-surfaces for a 3D volume of data supplied as arguments.

Function signatures:

```contour3d(scalars, ...)
contour3d(x, y, z, scalars, ...)
```

scalars is a 3D numpy arrays giving the data on a grid.

If 4 arrays, (x, y, z, scalars) are passed, the 3 first arrays give the position, and the last the scalar value. The x, y and z arrays are then supposed to have been generated by numpy.mgrid, in other words, they are 3D arrays, with positions lying on a 3D orthogonal and regularly spaced grid with nearest neighbor in space matching nearest neighbor in the array. The function builds a scalar field assuming the points are regularly spaced.

color 颜色

colormap 配色表

contours

Integer/list specifying number/list of contours. Specifying a list of values will only give the requested contours asked for.

extent 可视化范围

figure 图像参数

Figure to populate.

line_width 线宽设置

name 对象命名

opacity 透明度设置

reset_zoom

Reset the zoom to accomodate the data newly added to the scene. Defaults to True.

transparent

make the opacity of the actor depend on the scalar.

vmax 可视化范围（上界）

vmax将设定图像的配色区间，将图像对应vmax值的部分设定成配色表中的上界颜色。

vmin 可视化范围，下界设置

vmin将设定图像的配色区间，将图像对应vmin值的部分设定成配色表中的下界颜色。如果不设置，默认使用数据中值域下界作为vmin。

Example (run in `ipython --gui=qt`, or in the mayavi2 interactive shell, see 运行mlab脚本 for more info):

```import numpy
from mayavi.mlab import *

def test_contour3d():
x, y, z = np.ogrid[-5:5:64j, -5:5:64j, -5:5:64j]

scalars = x * x * 0.5 + y * y + z * z * 2.0

obj = contour3d(scalars, contours=4, transparent=True)
return obj
```

## contour_surf¶

mayavi.mlab.contour_surf(*args, **kwargs)

Plots a the contours of a surface using grid-spaced data for elevation supplied as a 2D array.

Function signatures:

```contour_surf(s, ...)
contour_surf(x, y, s, ...)
contour_surf(x, y, f, ...)
```

s is the elevation matrix, a 2D array. The contour lines plotted are lines of equal s value.

x and y can be 1D or 2D arrays (such as returned by numpy.ogrid or numpy.mgrid), but the points should be located on an orthogonal grid (possibly non-uniform). In other words, all the points sharing a same index in the s array need to have the same x or y value. For arbitrary-shaped position arrays (non-orthogonal grids), see the mesh function.

If only 1 array s is passed, the x and y arrays are assumed to be made from the indices of arrays, and an uniformly-spaced data set is created.

If 3 positional arguments are passed the last one must be an array s, or a callable, f, that returns an array. x and y give the coordinates of positions corresponding to the s values.

color 颜色

colormap 配色表

contours

Integer/list specifying number/list of contours. Specifying a list of values will only give the requested contours asked for.

extent 可视化范围

figure 图像参数

Figure to populate.

line_width 线宽设置

name 对象命名

opacity 透明度设置

reset_zoom

Reset the zoom to accomodate the data newly added to the scene. Defaults to True.

transparent

make the opacity of the actor depend on the scalar.

vmax 可视化范围（上界）

vmax将设定图像的配色区间，将图像对应vmax值的部分设定成配色表中的上界颜色。

vmin 可视化范围，下界设置

vmin将设定图像的配色区间，将图像对应vmin值的部分设定成配色表中的下界颜色。如果不设置，默认使用数据中值域下界作为vmin。

warp_scale

scale of the warp scalar

Example (run in `ipython --gui=qt`, or in the mayavi2 interactive shell, see 运行mlab脚本 for more info):

```import numpy
from mayavi.mlab import *

def test_contour_surf():
"""Test contour_surf on regularly spaced co-ordinates like MayaVi."""
def f(x, y):
sin, cos = np.sin, np.cos
return sin(x + y) + sin(2 * x - y) + cos(3 * x + 4 * y)

x, y = np.mgrid[-7.:7.05:0.1, -5.:5.05:0.05]
s = contour_surf(x, y, f)
return s
```

## flow¶

mayavi.mlab.flow(*args, **kwargs)

Creates a trajectory of particles following the flow of a vector field.

Function signatures:

```flow(u, v, w, ...)
flow(x, y, z, u, v, w, ...)
flow(x, y, z, f, ...)
```

u, v, w are numpy arrays giving the components of the vectors.

If only 3 arrays, u, v, and w are passed, they must be 3D arrays, and the positions of the arrows are assumed to be the indices of the corresponding points in the (u, v, w) arrays.

If 6 arrays, (x, y, z, u, v, w) are passed, the 3 first arrays give the position of the arrows, and the 3 last the components. The x, y and z arrays are then supposed to have been generated by numpy.mgrid, in other words, they are 3D arrays, with positions lying on a 3D orthogonal and regularly spaced grid with nearest neighbor in space matching nearest neighbor in the array. The function builds a vector field assuming the points are regularly spaced.

If 4 positional arguments, (x, y, z, f) are passed, the last one must be a callable, f, that returns vectors components (u, v, w) given the positions (x, y, z).

color 颜色

colormap 配色表

extent 可视化范围

figure 图像参数

Figure to populate.

integration_direction

The direction of the integration. Must be ‘forward’ or ‘backward’ or ‘both’. Default: forward

line_width 线宽设置

linetype

the type of line-like object used to display the streamline. Must be ‘line’ or ‘ribbon’ or ‘tube’. Default: line

name 对象命名

opacity 透明度设置

reset_zoom

Reset the zoom to accomodate the data newly added to the scene. Defaults to True.

scalars

optional scalar data.

seed_resolution

The resolution of the seed. Determines the number of seed points Must be an integer or None.

seed_scale

Scales the seed around its default center Must be a float. Default: 1.0

seed_visible

Control the visibility of the seed. Must be a boolean. Default: True

seedtype

the widget used as a seed for the streamlines. Must be ‘line’ or ‘plane’ or ‘point’ or ‘sphere’. Default: sphere

transparent

make the opacity of the actor depend on the scalar.

vmax 可视化范围（上界）

vmax将设定图像的配色区间，将图像对应vmax值的部分设定成配色表中的上界颜色。

vmin 可视化范围，下界设置

vmin将设定图像的配色区间，将图像对应vmin值的部分设定成配色表中的下界颜色。如果不设置，默认使用数据中值域下界作为vmin。

Example (run in `ipython --gui=qt`, or in the mayavi2 interactive shell, see 运行mlab脚本 for more info):

```import numpy
from mayavi.mlab import *

def test_flow():
x, y, z = np.mgrid[-4:4:40j, -4:4:40j, 0:4:20j]
r = np.sqrt(x ** 2 + y ** 2 + z ** 2 + 0.1)
u = y * np.sin(r) / r
v = -x * np.sin(r) / r
w = np.ones_like(z)*0.05
obj = flow(u, v, w)
return obj
```

## imshow¶

mayavi.mlab.imshow(*args, **kwargs)

View a 2D array as an image.

Function signatures:

```imshow(s, ...)
```

s is a 2 dimension array. The values of s are mapped to a color using the colormap.

color 颜色

colormap 配色表

extent 可视化范围

figure 图像参数

Figure to populate.

interpolate

if the pixels in the image are to be interpolated or not. Must be a boolean. Default: True

line_width 线宽设置

name 对象命名

opacity 透明度设置

the opacity of the image. Must be a legal value. Default: 1.0

reset_zoom

Reset the zoom to accomodate the data newly added to the scene. Defaults to True.

transparent

make the opacity of the actor depend on the scalar.

vmax 可视化范围（上界）

vmax将设定图像的配色区间，将图像对应vmax值的部分设定成配色表中的上界颜色。

vmin 可视化范围，下界设置

vmin将设定图像的配色区间，将图像对应vmin值的部分设定成配色表中的下界颜色。如果不设置，默认使用数据中值域下界作为vmin。

Example (run in `ipython --gui=qt`, or in the mayavi2 interactive shell, see 运行mlab脚本 for more info):

```import numpy
from mayavi.mlab import *

def test_imshow():
""" Use imshow to visualize a 2D 10x10 random array.
"""
s = np.random.random((10, 10))
return imshow(s, colormap='gist_earth')
```

## mesh¶

mayavi.mlab.mesh(*args, **kwargs)

Plots a surface using grid-spaced data supplied as 2D arrays.

Function signatures:

```mesh(x, y, z, ...)
```

x, y, z are 2D arrays, all of the same shape, giving the positions of the vertices of the surface. The connectivity between these points is implied by the connectivity on the arrays.

For simple structures (such as orthogonal grids) prefer the surf function, as it will create more efficient data structures. For mesh defined by triangles rather than regular implicit connectivity, see the triangular_mesh function.

color 颜色

colormap 配色表

extent 可视化范围

figure 图像参数

Figure to populate.

line_width 线宽设置

mask

boolean mask array to suppress some data points. Note: this works based on colormapping of scalars and will not work if you specify a solid color using the color keyword.

mask_points

If supplied, only one out of ‘mask_points’ data point is displayed. This option is useful to reduce the number of points displayed on large datasets Must be an integer or None.

mode

the mode of the glyphs. Must be ‘2darrow’ or ‘2dcircle’ or ‘2dcross’ or ‘2ddash’ or ‘2ddiamond’ or ‘2dhooked_arrow’ or ‘2dsquare’ or ‘2dthick_arrow’ or ‘2dthick_cross’ or ‘2dtriangle’ or ‘2dvertex’ or ‘arrow’ or ‘axes’ or ‘cone’ or ‘cube’ or ‘cylinder’ or ‘point’ or ‘sphere’. Default: sphere

name 对象命名

opacity 透明度设置

representation

the representation type used for the surface. Must be ‘surface’ or ‘wireframe’ or ‘points’ or ‘mesh’ or ‘fancymesh’. Default: surface

reset_zoom

Reset the zoom to accomodate the data newly added to the scene. Defaults to True.

resolution

The resolution of the glyph created. For spheres, for instance, this is the number of divisions along theta and phi. Must be an integer. Default: 8

scalars

optional scalar data.

scale_factor

scale factor of the glyphs used to represent the vertices, in fancy_mesh mode. Must be a float. Default: 0.05

scale_mode

the scaling mode for the glyphs (‘vector’, ‘scalar’, or ‘none’).

transparent

make the opacity of the actor depend on the scalar.

tube_radius

radius of the tubes used to represent the lines, in mesh mode. If None, simple lines are used.

tube_sides

number of sides of the tubes used to represent the lines. Must be an integer. Default: 6

vmax 可视化范围（上界）

vmax将设定图像的配色区间，将图像对应vmax值的部分设定成配色表中的上界颜色。

vmin 可视化范围，下界设置

vmin将设定图像的配色区间，将图像对应vmin值的部分设定成配色表中的下界颜色。如果不设置，默认使用数据中值域下界作为vmin。

Example (run in `ipython --gui=qt`, or in the mayavi2 interactive shell, see 运行mlab脚本 for more info):

```import numpy
from mayavi.mlab import *

def test_mesh():
"""A very pretty picture of spherical harmonics translated from
the octaviz example."""
pi = np.pi
cos = np.cos
sin = np.sin
dphi, dtheta = pi / 250.0, pi / 250.0
[phi, theta] = np.mgrid[0:pi + dphi * 1.5:dphi,
0:2 * pi + dtheta * 1.5:dtheta]
m0 = 4
m1 = 3
m2 = 2
m3 = 3
m4 = 6
m5 = 2
m6 = 6
m7 = 4
r = sin(m0 * phi) ** m1 + cos(m2 * phi) ** m3 + \
sin(m4 * theta) ** m5 + cos(m6 * theta) ** m7
x = r * sin(phi) * cos(theta)
y = r * cos(phi)
z = r * sin(phi) * sin(theta)

return mesh(x, y, z, colormap="bone")
```

## plot3d¶

mayavi.mlab.plot3d(*args, **kwargs)

Draws lines between points.

Function signatures:

```plot3d(x, y, z, ...)
plot3d(x, y, z, s, ...)
```

x, y, z and s are numpy arrays or lists of the same shape. x, y and z give the positions of the successive points of the line. s is an optional scalar value associated with each point.

color 颜色

colormap 配色表

extent 可视化范围

figure 图像参数

Figure to populate.

line_width 线宽设置

name 对象命名

opacity 透明度设置

representation

the representation type used for the surface. Must be ‘surface’ or ‘wireframe’ or ‘points’. Default: surface

reset_zoom

Reset the zoom to accomodate the data newly added to the scene. Defaults to True.

transparent

make the opacity of the actor depend on the scalar.

tube_radius

radius of the tubes used to represent the lines, If None, simple lines are used.

tube_sides

number of sides of the tubes used to represent the lines. Must be an integer. Default: 6

vmax 可视化范围（上界）

vmax将设定图像的配色区间，将图像对应vmax值的部分设定成配色表中的上界颜色。

vmin 可视化范围，下界设置

vmin将设定图像的配色区间，将图像对应vmin值的部分设定成配色表中的下界颜色。如果不设置，默认使用数据中值域下界作为vmin。

Example (run in `ipython --gui=qt`, or in the mayavi2 interactive shell, see 运行mlab脚本 for more info):

```import numpy
from mayavi.mlab import *

def test_plot3d():
"""Generates a pretty set of lines."""
n_mer, n_long = 6, 11
dphi = np.pi / 1000.0
phi = np.arange(0.0, 2 * np.pi + 0.5 * dphi, dphi)
mu = phi * n_mer
x = np.cos(mu) * (1 + np.cos(n_long * mu / n_mer) * 0.5)
y = np.sin(mu) * (1 + np.cos(n_long * mu / n_mer) * 0.5)
z = np.sin(n_long * mu / n_mer) * 0.5

l = plot3d(x, y, z, np.sin(mu), tube_radius=0.025, colormap='Spectral')
return l
```

## points3d¶

mayavi.mlab.points3d(*args, **kwargs)

Plots glyphs (like points) at the position of the supplied data.

Function signatures:

```points3d(x, y, z...)
points3d(x, y, z, s, ...)
points3d(x, y, z, f, ...)
```

x, y and z are numpy arrays, or lists, all of the same shape, giving the positions of the points.

If only 3 arrays x, y, z are given, all the points are drawn with the same size and color.

In addition, you can pass a fourth array s of the same shape as x, y, and z giving an associated scalar value for each point, or a function f(x, y, z) returning the scalar value. This scalar value can be used to modulate the color and the size of the points.

color 颜色

colormap 配色表

extent 可视化范围

figure 图像参数

Figure to populate.

line_width 线宽设置

mask_points

If supplied, only one out of ‘mask_points’ data point is displayed. This option is useful to reduce the number of points displayed on large datasets Must be an integer or None.

mode

the mode of the glyphs. Must be ‘2darrow’ or ‘2dcircle’ or ‘2dcross’ or ‘2ddash’ or ‘2ddiamond’ or ‘2dhooked_arrow’ or ‘2dsquare’ or ‘2dthick_arrow’ or ‘2dthick_cross’ or ‘2dtriangle’ or ‘2dvertex’ or ‘arrow’ or ‘axes’ or ‘cone’ or ‘cube’ or ‘cylinder’ or ‘point’ or ‘sphere’. Default: sphere

name 对象命名

opacity 透明度设置

reset_zoom

Reset the zoom to accomodate the data newly added to the scene. Defaults to True.

resolution

The resolution of the glyph created. For spheres, for instance, this is the number of divisions along theta and phi. Must be an integer. Default: 8

scale_factor

The scaling applied to the glyphs. the size of the glyph is by default calculated from the inter-glyph spacing. Specify a float to give the maximum glyph size in drawing units

scale_mode

the scaling mode for the glyphs (‘vector’, ‘scalar’, or ‘none’).

transparent

make the opacity of the actor depend on the scalar.

vmax 可视化范围（上界）

vmax将设定图像的配色区间，将图像对应vmax值的部分设定成配色表中的上界颜色。

vmin 可视化范围，下界设置

vmin将设定图像的配色区间，将图像对应vmin值的部分设定成配色表中的下界颜色。如果不设置，默认使用数据中值域下界作为vmin。

Example (run in `ipython --gui=qt`, or in the mayavi2 interactive shell, see 运行mlab脚本 for more info):

```import numpy
from mayavi.mlab import *

def test_points3d():
t = np.linspace(0, 4 * np.pi, 20)

x = np.sin(2 * t)
y = np.cos(t)
z = np.cos(2 * t)
s = 2 + np.sin(t)

return points3d(x, y, z, s, colormap="copper", scale_factor=.25)
```

## quiver3d¶

mayavi.mlab.quiver3d(*args, **kwargs)

Plots glyphs (like arrows) indicating the direction of the vectors at the positions supplied.

Function signatures:

```quiver3d(u, v, w, ...)
quiver3d(x, y, z, u, v, w, ...)
quiver3d(x, y, z, f, ...)
```

u, v, w are numpy arrays giving the components of the vectors.

If only 3 arrays, u, v, and w are passed, they must be 3D arrays, and the positions of the arrows are assumed to be the indices of the corresponding points in the (u, v, w) arrays.

If 6 arrays, (x, y, z, u, v, w) are passed, the 3 first arrays give the position of the arrows, and the 3 last the components. They can be of any shape.

If 4 positional arguments, (x, y, z, f) are passed, the last one must be a callable, f, that returns vectors components (u, v, w) given the positions (x, y, z).

color 颜色

colormap 配色表

extent 可视化范围

figure 图像参数

Figure to populate.

line_width 线宽设置

mask_points

If supplied, only one out of ‘mask_points’ data point is displayed. This option is useful to reduce the number of points displayed on large datasets Must be an integer or None.

mode

the mode of the glyphs. Must be ‘2darrow’ or ‘2dcircle’ or ‘2dcross’ or ‘2ddash’ or ‘2ddiamond’ or ‘2dhooked_arrow’ or ‘2dsquare’ or ‘2dthick_arrow’ or ‘2dthick_cross’ or ‘2dtriangle’ or ‘2dvertex’ or ‘arrow’ or ‘axes’ or ‘cone’ or ‘cube’ or ‘cylinder’ or ‘point’ or ‘sphere’. Default: 2darrow

name 对象命名

opacity 透明度设置

reset_zoom

Reset the zoom to accomodate the data newly added to the scene. Defaults to True.

resolution

The resolution of the glyph created. For spheres, for instance, this is the number of divisions along theta and phi. Must be an integer. Default: 8

scalars

optional scalar data.

scale_factor

The scaling applied to the glyphs. the size of the glyph is by default calculated from the inter-glyph spacing. Specify a float to give the maximum glyph size in drawing units

scale_mode

the scaling mode for the glyphs (‘vector’, ‘scalar’, or ‘none’).

transparent

make the opacity of the actor depend on the scalar.

vmax 可视化范围（上界）

vmax将设定图像的配色区间，将图像对应vmax值的部分设定成配色表中的上界颜色。

vmin 可视化范围，下界设置

vmin将设定图像的配色区间，将图像对应vmin值的部分设定成配色表中的下界颜色。如果不设置，默认使用数据中值域下界作为vmin。

Example (run in `ipython --gui=qt`, or in the mayavi2 interactive shell, see 运行mlab脚本 for more info):

```import numpy
from mayavi.mlab import *

def test_quiver3d():
x, y, z = np.mgrid[-2:3, -2:3, -2:3]
r = np.sqrt(x ** 2 + y ** 2 + z ** 4)
u = y * np.sin(r) / (r + 0.001)
v = -x * np.sin(r) / (r + 0.001)
w = np.zeros_like(z)
obj = quiver3d(x, y, z, u, v, w, line_width=3, scale_factor=1)
return obj
```

## set_picker_props¶

mayavi.mlab.set_picker_props(figure=None, pick_type='point_picker', tolerance=0.025, text_color=None)

## surf¶

mayavi.mlab.surf(*args, **kwargs)

Plots a surface using regularly-spaced elevation data supplied as a 2D array.

Function signatures:

```surf(s, ...)
surf(x, y, s, ...)
surf(x, y, f, ...)
```

s is the elevation matrix, a 2D array, where indices along the first array axis represent x locations, and indices along the second array axis represent y locations.

x and y can be 1D or 2D arrays such as returned by numpy.ogrid or numpy.mgrid. Arrays returned by numpy.meshgrid require a transpose first to obtain correct indexing order. The points should be located on an orthogonal grid (possibly non-uniform). In other words, all the points sharing a same index in the s array need to have the same x or y value. For arbitrary-shaped position arrays (non-orthogonal grids), see the mesh function.

If only 1 array s is passed, the x and y arrays are assumed to be made from the indices of arrays, and an uniformly-spaced data set is created.

If 3 positional arguments are passed the last one must be an array s, or a callable, f, that returns an array. x and y give the coordinates of positions corresponding to the s values.

color 颜色

colormap 配色表

extent 可视化范围

figure 图像参数

Figure to populate.

line_width 线宽设置

mask

boolean mask array to suppress some data points. Note: this works based on colormapping of scalars and will not work if you specify a solid color using the color keyword.

name 对象命名

opacity 透明度设置

representation

the representation type used for the surface. Must be ‘surface’ or ‘wireframe’ or ‘points’. Default: surface

reset_zoom

Reset the zoom to accomodate the data newly added to the scene. Defaults to True.

transparent

make the opacity of the actor depend on the scalar.

vmax 可视化范围（上界）

vmax将设定图像的配色区间，将图像对应vmax值的部分设定成配色表中的上界颜色。

vmin 可视化范围，下界设置

vmin将设定图像的配色区间，将图像对应vmin值的部分设定成配色表中的下界颜色。如果不设置，默认使用数据中值域下界作为vmin。

warp_scale

scale of the z axis (warped from the value of the scalar). By default this scale is a float value. If you specify ‘auto’, the scale is calculated to give a pleasant aspect ratio to the plot, whatever the bounds of the data. If you specify a value for warp_scale in addition to an extent, the warp scale will be determined by the warp_scale, and the plot be positioned along the z axis with the zero of the data centered on the center of the extent. If you are using explicit extents, this is the best way to control the vertical scale of your plots. If you want to control the extent (or range) of the surface object, rather than its scale, see the extent keyword argument.

Example (run in `ipython --gui=qt`, or in the mayavi2 interactive shell, see 运行mlab脚本 for more info):

```import numpy
from mayavi.mlab import *

def test_surf():
"""Test surf on regularly spaced co-ordinates like MayaVi."""
def f(x, y):
sin, cos = np.sin, np.cos
return sin(x + y) + sin(2 * x - y) + cos(3 * x + 4 * y)

x, y = np.mgrid[-7.:7.05:0.1, -5.:5.05:0.05]
s = surf(x, y, f)
#cs = contour_surf(x, y, f, contour_z=0)
return s
```

## triangular_mesh¶

mayavi.mlab.triangular_mesh(*args, **kwargs)

Plots a surface using a mesh defined by the position of its vertices and the triangles connecting them.

Function signatures:

```triangular_mesh(x, y, z, triangles ...)
```

x, y, z are arrays giving the positions of the vertices of the surface. triangles is a list of triplets (or an array) list the vertices in each triangle. Vertices are indexes by their appearance number in the position arrays.

For simple structures (such as rectangular grids) prefer the surf or mesh functions, as they will create more efficient data structures.

color 颜色

colormap 配色表

extent 可视化范围

figure 图像参数

Figure to populate.

line_width 线宽设置

mask

boolean mask array to suppress some data points. Note: this works based on colormapping of scalars and will not work if you specify a solid color using the color keyword.

mask_points

If supplied, only one out of ‘mask_points’ data point is displayed. This option is useful to reduce the number of points displayed on large datasets Must be an integer or None.

mode

the mode of the glyphs. Must be ‘2darrow’ or ‘2dcircle’ or ‘2dcross’ or ‘2ddash’ or ‘2ddiamond’ or ‘2dhooked_arrow’ or ‘2dsquare’ or ‘2dthick_arrow’ or ‘2dthick_cross’ or ‘2dtriangle’ or ‘2dvertex’ or ‘arrow’ or ‘axes’ or ‘cone’ or ‘cube’ or ‘cylinder’ or ‘point’ or ‘sphere’. Default: sphere

name 对象命名

opacity 透明度设置

representation

the representation type used for the surface. Must be ‘surface’ or ‘wireframe’ or ‘points’ or ‘mesh’ or ‘fancymesh’. Default: surface

reset_zoom

Reset the zoom to accomodate the data newly added to the scene. Defaults to True.

resolution

The resolution of the glyph created. For spheres, for instance, this is the number of divisions along theta and phi. Must be an integer. Default: 8

scalars

optional scalar data.

scale_factor

scale factor of the glyphs used to represent the vertices, in fancy_mesh mode. Must be a float. Default: 0.05

scale_mode

the scaling mode for the glyphs (‘vector’, ‘scalar’, or ‘none’).

transparent

make the opacity of the actor depend on the scalar.

tube_radius

radius of the tubes used to represent the lines, in mesh mode. If None, simple lines are used.

tube_sides

number of sides of the tubes used to represent the lines. Must be an integer. Default: 6

vmax 可视化范围（上界）

vmax将设定图像的配色区间，将图像对应vmax值的部分设定成配色表中的上界颜色。

vmin 可视化范围，下界设置

vmin将设定图像的配色区间，将图像对应vmin值的部分设定成配色表中的下界颜色。如果不设置，默认使用数据中值域下界作为vmin。

Example (run in `ipython --gui=qt`, or in the mayavi2 interactive shell, see 运行mlab脚本 for more info):

```import numpy
from mayavi.mlab import *

def test_triangular_mesh():
"""An example of a cone, ie a non-regular mesh defined by its
triangles.
"""
n = 8
t = np.linspace(-np.pi, np.pi, n)
z = np.exp(1j * t)
x = z.real.copy()
y = z.imag.copy()
z = np.zeros_like(x)

triangles = [(0, i, i + 1) for i in range(1, n)]
x = np.r_[0, x]
y = np.r_[0, y]
z = np.r_[1, z]
t = np.r_[0, t]

return triangular_mesh(x, y, z, triangles, scalars=t)
```

## volume_slice¶

mayavi.mlab.volume_slice(*args, **kwargs)

Plots an interactive image plane sliced through a 3D volume of data supplied as argument.

Function signatures:

```volume_slice(scalars, ...)
volume_slice(x, y, z, scalars, ...)
```

scalars is a 3D numpy arrays giving the data on a grid.

If 4 arrays, (x, y, z, scalars) are passed, the 3 first arrays give the position, and the last the scalar value. The x, y and z arrays are then supposed to have been generated by numpy.mgrid, in other words, they are 3D arrays, with positions lying on a 3D orthogonal and regularly spaced grid with nearest neighbor in space matching nearest neighbor in the array. The function builds a scalar field assuming the points are regularly spaced.

color 颜色

colormap 配色表

extent 可视化范围

figure 图像参数

Figure to populate.

line_width 线宽设置

name 对象命名

opacity 透明度设置

plane_opacity

the opacity of the plane actor. Must be a legal value. Default: 1.0

plane_orientation

the orientation of the plane Must be a legal value. Default: x_axes

reset_zoom

Reset the zoom to accomodate the data newly added to the scene. Defaults to True.

slice_index

The index along with the image is sliced.

transparent

make the opacity of the actor depend on the scalar.

vmax 可视化范围（上界）

vmax将设定图像的配色区间，将图像对应vmax值的部分设定成配色表中的上界颜色。

vmin 可视化范围，下界设置

vmin将设定图像的配色区间，将图像对应vmin值的部分设定成配色表中的下界颜色。如果不设置，默认使用数据中值域下界作为vmin。

Example (run in `ipython --gui=qt`, or in the mayavi2 interactive shell, see 运行mlab脚本 for more info):

```import numpy
from mayavi.mlab import *

def test_volume_slice():
x, y, z = np.ogrid[-5:5:64j, -5:5:64j, -5:5:64j]

scalars = x * x * 0.5 + y * y + z * z * 2.0

obj = volume_slice(scalars, plane_orientation='x_axes')
return obj
```