## Using Python for 3D Plotting

Using Python for 3D plotting is a powerful tool that can assist engineers, scientists, and data analysts to create 3D models of complex systems. This revolutionary method of creating 3D models is comparatively easy and simple to learn.

In this article, we will cover the essential methods required for plotting in 3D and walk through an example of creating a Solenoid using .plot3D() in Python.

### 1. Essential Libraries for 3D Plotting

To plot in 3D, Python relies on certain libraries, such as NumPy, SciPy, and matplotlib. These libraries allow users to create and manipulate 3D plots of various types.

### 2. Understanding the Mechanics of 3D Plotting

To create a 3D plot of a system, one must first understand some of the fundamental methods and principles of plotting in 3D. NumPy’s linspace() method is an excellent way to create a linear array of numbers within a defined range.

This method is a potent tool as it allows for finer quality control, especially when plotting 3D models. The mgrid method, which is a multidimensional version of linspace, returns an N-dimensional meshgrid where one can evaluate an N-dimensional function at N points.

The resulting arrays can then be used to create 3D plots. Together with the numpy.linspace() function, they are invaluable tools for creating 3D plots of various types.

### 3. Plotting a 3D Model using .plot3D() method

Now that we understand the mechanics of creating 3D plots let us delve into a practical example of creating a Solenoid. A Solenoid is an electromechanical device whose primary function is to produce electromagnetism when an electric current flows through it.

### We will make use of Numpy and Matplotlib modules for this practical example:

```
# Importing required libraries
import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D
```

The next step is to create the meshgrid that will be used to plot the 3D coordinates of the solenoid. This involves setting the X, Y, and Z-axis boundaries, as shown below:

```
# Create meshgrid for 3D plot
x = np.linspace(-2, 2, 1000)
y = np.linspace(-2, 2, 1000)
z = np.linspace(-5, 5, 1000)
X, Y, Z = np.meshgrid(x, y, z)
```

After creating the meshgrid, we can move on to the next step, which involves creating the actual 3D Solenoid.

Here, we will make use of NumPy’s sin and cos mathematical functions to manipulate the values of X, Y, and Z to create the Solenoid’s 3D structure.

```
# Create 3D Solenoid using numpy sin and cos
R = 1
a = 1
b = 1
theta = np.linspace(0, 2*np.pi, 1000)
x = np.outer((R + a * np.cos(theta)), np.cos(2*np.pi*Z/b))
y = np.outer((R + a * np.cos(theta)), np.sin(2*np.pi*Z/b))
z = np.outer(a * np.sin(theta), np.ones_like(Z))
```

Finally, we can plot the Solenoid using the plot3D method provided by the mplot3d module.

This 3D plot is fully interactive, and one can pan, zoom, and rotate the image using mouse clicks.

```
# Plot the created Solenoid
fig = plt.figure('Solenoid')
ax = fig.add_subplot(111, projection='3d')
ax.plot_surface(x, y, z, color='c')
ax.set_xlabel('X-axis')
ax.set_ylabel('Y-axis')
ax.set_zlabel('Z-axis')
plt.show()
```

By executing this script in a Python environment, we can successfully create a 3D Solenoid plotted on the X, Y, and Z-axis.

## Conclusion

In conclusion, creating 3D plots in Python can be complex, but with the right modules such as Matplotlib, Numpy, and mplot3d, it becomes a straightforward process. The key is to have an in-depth understanding of the plotting methods and mathematical functions required to create different types of 3D plots.

In this article, we have walked through the two primary methods required for plotting in 3D, namely numpy.linspace() and numpy.mgrid. Additionally, we provided a step-by-step example of how to create a 3D Solenoid in Python using Matplotlib, Numpy, and mplot3d.

### 4. Plotting a 3D Model using .scatter3D() method

The scatter3D() method in Python’s mplot3d module is used to plot 3D datasets as scattered points. This method is useful when one needs to visualize 3D data points in a broad range and is suitable for creating simple 3D models.

### Let us walk through an example of creating a Scattered Dotted Solenoid in a 3D Graph using Python:

```
# Importing required libraries
import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D
# Create meshgrid for 3D plot
x = np.linspace(-2, 2, 1000)
y = np.linspace(-2, 2, 1000)
z = np.linspace(-5, 5, 1000)
X, Y, Z = np.meshgrid(x, y, z)
# Create 3D Solenoid using numpy sin and cos
R = 1
a = 1
b = 1
theta = np.linspace(0, 2*np.pi, 1000)
x = np.outer((R + a * np.cos(theta)), np.cos(2*np.pi*Z/b))
y = np.outer((R + a * np.cos(theta)), np.sin(2*np.pi*Z/b))
z = np.outer(a * np.sin(theta), np.ones_like(Z))
# Create Scattered Dotted Solenoid
x_coords = x.ravel()
y_coords = y.ravel()
z_coords = z.ravel()
c = np.random.random(len(x_coords))
fig = plt.figure('Scattered Dotted Solenoid')
ax = fig.add_subplot(111, projection='3d')
ax.scatter3D(x_coords, y_coords, z_coords, c=c, cmap='hsv', s=1)
ax.set_xlabel('X-axis')
ax.set_ylabel('Y-axis')
ax.set_zlabel('Z-axis')
plt.show()
```

In the above code, we use the scatter3D() method to create a Scattered Dotted Solenoid using the x, y, and z coordinates we defined earlier. Additionally, we generate a random color array and assign it to the “c” parameter in scatter3D() so that each point has a different color.

Finally, by adjusting the “s” parameter, we control the size of the dots, and we set the “cmap” parameter to ‘hsv’ to obtain a more vibrant look.

### 5. Plotting a Surface from a List of Tuples

Apart from meshgrid function, a list of tuples can also be used to create surfaces in Python. To plot the surface, one will need to pass the x, y, and z datapoints as separate lists of tuples.

### Let us look at an example of plotting the surface for some tuples in Python:

```
# Importing required libraries
import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D
# Creating List of Tuples
data = [(1, 1, 2), (2, 1, 4), (3, 1, 7), (1, 2, 3), (2, 2, 5), (3, 2, 8), (1, 3, 4), (2, 3, 6), (3, 3, 9)]
# Unpacking Data to separate coordinate arrays
x, y, z = zip(*data)
# Reshaping coordinate arrays
x = np.asarray(x).reshape((3,3))
y = np.asarray(y).reshape((3,3))
z = np.asarray(z).reshape((3,3))
# Creating surface plot
fig = plt.figure('Surface Plot')
ax = fig.add_subplot(111, projection='3d')
ax.plot_surface(x, y, z)
ax.set_xlabel('X-axis')
ax.set_ylabel('Y-axis')
ax.set_zlabel('Z-axis')
plt.show()
```

In the above script, we use the zip() method to unpack our data list, containing tuples of (x, y, z), into separate lists. We then reshape these lists into 2D NumPy arrays that can be used for plotting surfaces.

Finally, we plot the surface using the plot_surface() method provided by the mplot3d module.

### 6. Plotting a 3D Model using .plot_surface() method

Python’s mplot3d module provides an assortment of methods for plotting 3D models. The plot_surface() method is a powerful tool that can create 3D models of various shapes and sizes.

Here, we will explore how to use this method to plot points on the surface of a sphere. To generate points on the surface of a sphere, one must first define a set of spherical coordinates.

Typically, these coordinates are represented as a tuple with three values: the radius, inclination angle, and azimuth angle. The radius determines the size of the sphere, while the inclination and azimuth angles are used to position the point on the sphere.

Using these spherical coordinates, we can define the location of the points that make up the surface of the sphere. Let us look at an example of how to plot points on the surface of a sphere in Python:

```
# Importing required libraries
import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D
# Define Spherical Coordinates
theta = np.linspace(0, np.pi, 100)
phi = np.linspace(0, 2*np.pi, 100)
theta, phi = np.meshgrid(theta, phi)
# Convert Spherical to Cartesian Coordinates
x = np.sin(theta) * np.cos(phi)
y = np.sin(theta) * np.sin(phi)
z = np.cos(theta)
# Create Surface Plot
fig = plt.figure('Sphere Surface')
ax = fig.add_subplot(111, projection='3d')
ax.plot_surface(x, y, z)
ax.set_xlabel('X-axis')
ax.set_ylabel('Y-axis')
ax.set_zlabel('Z-axis')
plt.show()
```

In the above script, we define the spherical coordinates for the points on the surface of the sphere. We then use NumPy’s meshgrid() function to create a mesh of these points.

Next, we convert these spherical coordinates to Cartesian coordinates using the standard conversion formulas. Finally, we plot these points as a surface using the plot_surface() method provided by the mplot3d module.

## Summary

In summary, we have covered the essential methods required for plotting 3D models in Python. We initially discussed numpy.linespace() and numpy.mgrid, which are both valuable tools for creating linear arrays of numbers for finer quality control in 3D plotting.

We then covered the plot3D() method, which is useful for visualizing simple 3D models. The scatter3D() method is a powerful tool for visualizing 3D datasets as scattered points.

Furthermore, we discussed plotting surfaces from a list of tuples and using the plot_surface() method to create surfaces of different shapes and sizes. In the article, we presented practical examples, such as creating a solenoid and plotting points on the surface of a sphere.

These examples demonstrated how to use the methods covered in this article to create and visualize different 3D models. By understanding these methods and applying them to different use-cases, one can create various types of 3D plots that can assist professionals in different fields to visualize their data and gain insights into complex systems.

In conclusion, Python’s 3D plotting libraries provide a wealth of tools that can be used to create and manipulate 3D models. By implementing the methods outlined in this article and using the examples provided, users can develop the skills required to create 3D visualizations of their data in Python.

This skill set can be used in numerous applications, such as data analysis, scientific visualization, computer graphics, and more. In conclusion, this article explored the different methods required for plotting 3D models in Python, such as linspace(), mgrid, plot3D(), scatter3D(), and plot_surface().

We have walked through several practical examples that demonstrated how to utilize these methods, including creating a Solenoid, a Scattered Dotted Solenoid, plotting a surface from a list of tuples, and defining and plotting the points on the surface of a sphere. These examples highlight the flexibility and versatility of Python’s 3D plotting libraries, making it an essential toolset for engineers, scientists, and data analysts.

The takeaways from this article are that by understanding the methods and applying them to different applications, one can create complex 3D models swiftly and efficiently in Python, offering valuable insights into the underlying data and enhancing the user’s decision-making capabilities.