python-将x，y，z值映射到2D表面数据

Question

I have the following data set:

x = [50.0,  55.0,   6.6,    35.0,   32.7,   33.2,   14.9,   60.0,   44.0,   38.1]
y = [50.0,  25.0,   47.4,   34.9,   56.3,   78.4,   81.9,   73.4,   46.8    ,65.6]
z = [0.3,   -1.5,   0.1,    1.0,    1.9,    -0.1,   -0.4,   -0.1,   0.3,    -0.0]   

x and y is the location of the sample data point on a 2D surface. z is the value of the data sample at the location.

Essentially I want something something like this:

However, as you can see, z values are not yet mapped into 2D grid format.

This is NOT what I want:

x = np.arange(-5, 5, 0.1)
y = np.arange(-5, 5, 0.1)
xx, yy = np.meshgrid(x, y, sparse=True)
z = np.sin(xx**2 + yy**2) / (xx**2 + yy**2)

All the examples I found online calculates z matrix assuming some contour plot, but that's not the case for me. In my case, z is 1D array that contains the, say, gold percentage of a rock at the sample locations, and x and y accounts for the location of that sample.

How can I convert the z array into 2D matrix that accounts for the location of the sample?

At the end, I want to make a scatter plot using the 2D transformed_z matrix.

random_sample = transformed_z[x,y]
ax.scatter(y,x,c=transformed_z, cmap=im.cmap, norm=im.norm)

Answer 1

IIUC you just want to plot the values in z as a color coded scatterplot with x and y as coordinates.

You do not need to transform z for this purpose, this can be done purely with the given three arrays as they are:

import matplotlib.pyplot as plt

x = [50.0,  55.0,   6.6,    35.0,   32.7,   33.2,   14.9,   60.0,   44.0,   38.1]
y = [50.0,  25.0,   47.4,   34.9,   56.3,   78.4,   81.9,   73.4,   46.8    ,65.6]
z = [0.3,   -1.5,   0.1,    1.0,    1.9,    -0.1,   -0.4,   -0.1,   0.3,    -0.0]

plt.figure()

plt.scatter(x, y, c=z, cmap='Wistia')
cb = plt.colorbar()
cb.set_label('gold percentage of a rock (%)')
plt.xlabel('X')
plt.ylabel('Y')

for xt, yt, zt in zip(x, y, z):
    plt.text(xt, yt+1, str(zt), ha='center')

I've added the values as text for faster comparison with the arrays.