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# 3D Surface plotting in Python using Matplotlib

• Difficulty Level : Medium
• Last Updated : 30 Apr, 2020

A Surface Plot is a representation of three-dimensional dataset. It describes a functional relationship between two independent variables X and Z and a designated dependent variable Y, rather than showing the individual data points. It is a companion plot of the contour plot. It is similar to the wireframe plot, but each face of the wireframe is a filled polygon. This helps to create the topology of the surface which is being visualized.

## Creating 3D surface Plot

The `axes3d` present in Matplotlib’s `mpl_toolkits.mplot3d` toolkit provides the necessary functions used to create 3D surface plots.Surface plots are created by using `ax.plot_surface()` function.

Syntax:

`ax.plot_surface(X, Y, Z)`

where X and Y are 2D array of points of x and y while Z is 2D array of heights.Some more attributes of `ax.plot_surface()` function are listed below:

AttributeDescription
X, Y, Z2D arrays of data values
cstridearray of column stride(step size)
rstridearray of row stride(step size)
ccountnumber of colums to be used, default is 50
rcountnumber of row to be used, default is 50
colorcolor of the surface
cmapcolormap for the surface
norminstance to normalize values of color map
vminminimum value of map
vmaxmaximum value of map
facecolorsface color of individual surface

Example: Let’s create a 3D surface by using the above function

 `# Import libraries``from` `mpl_toolkits ``import` `mplot3d``import` `numpy as np``import` `matplotlib.pyplot as plt`` ` ` ` `# Creating dataset``x ``=` `np.outer(np.linspace(``-``3``, ``3``, ``32``), np.ones(``32``))``y ``=` `x.copy().T ``# transpose``z ``=` `(np.sin(x ``*``*``2``) ``+` `np.cos(y ``*``*``2``) )`` ` `# Creating figyre``fig ``=` `plt.figure(figsize ``=``(``14``, ``9``))``ax ``=` `plt.axes(projection ``=``'3d'``)`` ` `# Creating plot``ax.plot_surface(x, y, z)`` ` `# show plot``plt.show()`

Output: Gradient surface plot is a combination of 3D surface plot with a 2D contour plot. In this plot the 3D surface is colored like 2D contour plot. The parts which are high on the surface contains different color than the parts which are low at the surface.

Syntax:

surf = ax.plot_surface(X, Y, Z, cmap=, linewidth=0, antialiased=False)

The attribute `cmap=` stes the color of the surface. A color bar can also be added by calling `fig.colorbar`. The code below create a gradient surface plot:

Example:

 `# Import libraries``from` `mpl_toolkits ``import` `mplot3d``import` `numpy as np``import` `matplotlib.pyplot as plt`` ` `# Creating dataset``x ``=` `np.outer(np.linspace(``-``3``, ``3``, ``32``), np.ones(``32``))``y ``=` `x.copy().T ``# transpose``z ``=` `(np.sin(x ``*``*``2``) ``+` `np.cos(y ``*``*``2``) )`` ` `# Creating figyre``fig ``=` `plt.figure(figsize ``=``(``14``, ``9``))``ax ``=` `plt.axes(projection ``=``'3d'``)`` ` `# Creating color map``my_cmap ``=` `plt.get_cmap(``'hot'``)`` ` `# Creating plot``surf ``=` `ax.plot_surface(x, y, z,``                       ``cmap ``=` `my_cmap,``                       ``edgecolor ``=``'none'``)`` ` `fig.colorbar(surf, ax ``=` `ax,``             ``shrink ``=` `0.5``, aspect ``=` `5``)`` ` `ax.set_title(``'Surface plot'``)`` ` `# show plot``plt.show()`

Output: ## 3D surface Plot having 2D contour plot projections

3D surface plots plotted with Matplotlib can be projected on 2D surfaces. The code below creates a 3D plots and visualizes its projection on 2D contour plot:

Example:

 `# Import libraries``from` `mpl_toolkits ``import` `mplot3d``import` `numpy as np``import` `matplotlib.pyplot as plt`` ` `# Creating dataset``x ``=` `np.outer(np.linspace(``-``3``, ``3``, ``32``), np.ones(``32``))``y ``=` `x.copy().T ``# transpose``z ``=` `(np.sin(x ``*``*``2``) ``+` `np.cos(y ``*``*``2``) )`` ` `# Creating figyre``fig ``=` `plt.figure(figsize ``=``(``14``, ``9``))``ax ``=` `plt.axes(projection ``=``'3d'``)`` ` `# Creating color map``my_cmap ``=` `plt.get_cmap(``'hot'``)`` ` `# Creating plot``surf ``=` `ax.plot_surface(x, y, z, ``                       ``rstride ``=` `8``,``                       ``cstride ``=` `8``,``                       ``alpha ``=` `0.8``,``                       ``cmap ``=` `my_cmap)``cset ``=` `ax.contourf(x, y, z,``                   ``zdir ``=``'z'``,``                   ``offset ``=` `np.``min``(z),``                   ``cmap ``=` `my_cmap)``cset ``=` `ax.contourf(x, y, z,``                   ``zdir ``=``'x'``,``                   ``offset ``=``-``5``,``                   ``cmap ``=` `my_cmap)``cset ``=` `ax.contourf(x, y, z, ``                   ``zdir ``=``'y'``,``                   ``offset ``=` `5``,``                   ``cmap ``=` `my_cmap)``fig.colorbar(surf, ax ``=` `ax, ``             ``shrink ``=` `0.5``,``             ``aspect ``=` `5``)`` ` `# Adding labels``ax.set_xlabel(``'X-axis'``)``ax.set_xlim(``-``5``, ``5``)``ax.set_ylabel(``'Y-axis'``)``ax.set_ylim(``-``5``, ``5``)``ax.set_zlabel(``'Z-axis'``)``ax.set_zlim(np.``min``(z), np.``max``(z))``ax.set_title(``'3D surface having 2D contour plot projections'``)`` ` `# show plot``plt.show()`

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