Question

我想从python脚本制作一个pascal三角形。这是我从web.programminghub.io

获得的语法

size = int(input("Enter the size of the triangle: ")) 
tri=[]

#creates a pascal triangle of size n
def pascal(n):
   """Prints out n rows of Pascal's triangle.
   It returns False for failure and True for success."""
   row = [1]
   k = [0]
   for x in range(max(n,0)):
      tri.append(row)
      row=[l+r for l,r in zip(row+k,k+row)]
   return n>=1


#prints the pascal triangle with correct spacing to 
#represent a triangle
def print_pascals_triangle(triangle):
    largest_element = triangle[-1][len(triangle[-1]) // 2]
    element_width = len(str(largest_element))
    def format_row(row):
        return ' '.join([str(element).center(element_width) 
for element in row])
    triangle_width = len(format_row(triangle[-1]))
    for row in triangle:
        print(format_row(row).center(triangle_width)) 
pascal(size)

print_pascals_triangle(tri)

问题是，没有解释此脚本代码中的每一行。所以有人可以解释这种语法含义的每一行。

Answer 1

第一个函数pascal生成存储在tri中的pascal三角形。 print_pascals_triangle对称地打印三角形。

Enter the size of the triangle: 3
  1  
 1 1 
1 2 1

pascal生成[[1], [1, 1], [1, 2, 1]]。

print_pascals_triangle打印以固定宽度（triangle_width）为中心的每一行。

python3.x语法的含义

1 个答案: