我有一个充满有序对的巨大列表,我想选择所有具有相同第一个值的嵌套列表。我会怎么做?例如,在下面的代码中,我想选择所有具有19作为第一个值的列表。如何选择所有以大嵌套列表中的相同值开头的列表?
import numpy as np
radius = 10
origin=(10,10)
def circle(radius): #init vars
switch = 3 - (2 * radius)
points = set()
x = 0
y = radius
while x <= y: #first octant starts clockwise at 12 o'clock
points.add((x,-y)) #1st oct
points.add((y,-x)) #2nd oct
points.add((y,x)) #3rd oct
points.add((x,y)) #4th oct
points.add((-x,y)) #5th oct
points.add((-y,x)) #6th oct
points.add((-y,-x)) #7th oct
points.add((-x,-y)) #8th oct
if switch < 0:
switch=switch+(4*x)+6
else:
switch=switch+(4*(x-y))+10
y=y-1
x=x+1
return points
cp = list(circle(radius))
cp1=np.array(cp)
center=list(origin)
cp1=cp1+center
cp2=cp1.tolist()
cp2.sort()
desmos=list(tuple(x) for x in cp2)
print(cp2)
'名单(过滤器(lambda x:x [0] == 19,nestedList))' –
'[x for nestedList if x [0] == 19]' –