将 function 值列表转换为二维数组

Question

Suppose I have a text file whose lines contain three values (2 coordinates and the value of a function evaluated at those coordinates):

x y f(x, y)

Using numpy, how do I convert this data (read using genfromtxt , say) to an array of x values, an array of y values and a 2D array of function values, such that I can visualize f(x, y) using matplotlib 's imshow , for example?

Edit: Easily done by using panda 's pivot_table .

Answer 1

This code will get you started. It will grab the input from file one line at a time, and parse the values from each line. You can then do what you want with the values (append them to a list, for example, then convert the list to a numpy data structure)

with open(filename) as file:
  for line in file:
    elements = line.split(" ")
    x = elements[0]
    y = elements[1]
    f_x_y = elements[2]

Good luck on your Python journey!