X = [0.1, 0.7 , 1, 1.35]

import numpy as np

   X = map(np.array,[X])
   X = [0.1, 0.5 , 1, 1.5]
   X = ( X[:,None] + X[:] )

 #Результат
 [[ 0.2   0.8   1.1   1.45]
  [ 0.8   1.4   1.7   2.05]
  [ 1.1   1.7   2.    2.35]
  [ 1.45  2.05  2.35  2.7 ]]

[[  0.8   1.1   1.45]
    [ 0.8    1.7   2.05]
    [ 1.1    1.7    2.35]
    [ 1.45   2.05   2.35 ]]

Y = [0.3, 0.5, 0.7, 0.9]

     (X[:,None] + X[:]) + (Y[:,None] + Y[:])

X[:,None] + Y[:]

def f(array):
    new = [x+y for x in array for y in array if y!=x]
    return new

print(f([1, 2, 3]))

[3, 4,
3, 5,
4, 5]

def for_stack(array):
    list_for_num_array = []
    for i in array:
        list_for_num_array.append([x+y for x in i for y in i if y!= x])
    return np.array(list_for_num_array)
X = np.array([[0.1, 0.7 , 1, 1.35]])
print(for_stack(X[:None]))

[[ 0.8, 1.1, 1.45,
   0.8, 1.7, 2.05,
   1.1, 1.7, 2.35,
   1.45, 2.05, 2.35]]

foo = lambda array: ([j+n for i in array for x, j in enumerate(i) for y, n in enumerate(i) if x != y])

def for_stack(array):
    list_for_num_array = []
    for i in array:
        list_for_num_array.append([j+n for x, j in enumerate(i) for y, n in enumerate(i) if x != y])
    return np.array(list_for_num_array)
X = np.array([[1, 2, 2], [1, 2, 2]])
print(for_stack(X[:None]))

[[3 3 3 4 3 4],
 [3 3 3 4 3 4]]

def for_stack(array):
    list_for_num_array = []
    try:
        for i, j in enumerate(array):
                list_for_num_array.append([x+n for x, n in zip(array[i], array[i+1])])
    except IndexError:
            pass
    return np.array(list_for_num_array)
X = np.array([[0.1, 0.7 , 1, 1.35], [2, 3, 4, 5]])
print(for_stack(X[:None]))

[[ 2.1   3.7   5.    6.35]]

arr = np.array([[1, 2, 3],
            [4, 5, 6],
            [7, 8, 9]])
foo = lambda array: np.delete(array, diagonal(array-1))

[[2 3 4 6 7 8]]

In [221]: X = np.array([0.1, 0.7 , 1, 1.35])

In [222]: l = len(X)

In [223]: A = np.delete(X[:,None] + X[:], np.arange(0, l**2, l+1)).reshape(l,l-1)

In [224]: A
Out[224]:
array([[ 0.8 ,  1.1 ,  1.45],
       [ 0.8 ,  1.7 ,  2.05],
       [ 1.1 ,  1.7 ,  2.35],
       [ 1.45,  2.05,  2.35]])

In [225]: A.sum(axis=1)
Out[225]: array([ 3.35,  4.55,  5.15,  5.85])

In [228]: np.delete(X[:,None] + X[:], 5)
Out[228]: array([ 0.2 ,  0.8 ,  1.1 ,  1.45,  0.8 ,  1.7 ,  2.05,  1.1 ,  1.7 ,  2.  ,  2.35,  1.45,  2.05,  2.35,  2.7 ])

In [229]: np.arange(0, l**2, l+1)
Out[229]: array([ 0,  5, 10, 15])

In [230]: np.delete(X[:,None] + X[:], np.arange(0, l**2, l+1))
Out[230]: array([ 0.8 ,  1.1 ,  1.45,  0.8 ,  1.7 ,  2.05,  1.1 ,  1.7 ,  2.35,  1.45,  2.05,  2.35])

In [231]: np.delete(X[:,None] + X[:], np.arange(0, l**2, l+1)).reshape(l,l-1)
Out[231]:
array([[ 0.8 ,  1.1 ,  1.45],
       [ 0.8 ,  1.7 ,  2.05],
       [ 1.1 ,  1.7 ,  2.35],
       [ 1.45,  2.05,  2.35]])