In [1]:

    

import numpy as np


    

In [2]:

    

a= np.array([[1, 2, 3, 4], [4, 6, 8, 10], [9, 11, 13, 15]])


    

In [3]:

    

a


    

    
Out[3]:





array([[ 1,  2,  3,  4],
       [ 4,  6,  8, 10],
       [ 9, 11, 13, 15]])

In [4]:

    

np.gradient(a, axis=0)  # along y axis


    

    
Out[4]:





array([[3. , 4. , 5. , 6. ],
       [4. , 4.5, 5. , 5.5],
       [5. , 5. , 5. , 5. ]])

In [5]:

    

np.gradient(a, axis=1)  # along x axis


    

    
Out[5]:





array([[1., 1., 1., 1.],
       [2., 2., 2., 2.],
       [2., 2., 2., 2.]])

In [6]:

    

from math import pi
from numpy import array


    

In [7]:

    

from pygsf.spatial.rasters.fields import *


    

In [8]:

    

fld1 = array([
   [1, 1, 1, 1],
   [1, 1, 1, 1],
   [1, 1, 1, 1]])


    

In [9]:

    

grad_j(fld1, cell_size_j=10)


    

    
Out[9]:





array([[0., 0., 0., 0.],
       [0., 0., 0., 0.],
       [0., 0., 0., 0.]])

In [10]:

    

grad_i(fld1, cell_size_i=10)


    

    
Out[10]:





array([[0., 0., 0., 0.],
       [0., 0., 0., 0.],
       [0., 0., 0., 0.]])

In [11]:

    

fld2 = array([
   [10, 10, 10, 10],
   [20, 20, 20, 20],
   [30, 30, 30, 30]])


    

In [12]:

    

grad_j(fld2, cell_size_j=10)


    

    
Out[12]:





array([[0., 0., 0., 0.],
       [0., 0., 0., 0.],
       [0., 0., 0., 0.]])

In [13]:

    

grad_i(fld2, cell_size_i=10)


    

    
Out[13]:





array([[1., 1., 1., 1.],
       [1., 1., 1., 1.],
       [1., 1., 1., 1.]])

In [14]:

    

dir_deriv(fld2, cell_size_x=10, cell_size_y=10, direct_rad=pi*45.0/180.0)


    

    
Out[14]:





array([[-0.70710678, -0.70710678, -0.70710678, -0.70710678],
       [-0.70710678, -0.70710678, -0.70710678, -0.70710678],
       [-0.70710678, -0.70710678, -0.70710678, -0.70710678]])

In [15]:

    

dir_deriv(fld2, cell_size_x=10, cell_size_y=10, direct_rad=pi*0.0/180.0)


    

    
Out[15]:





array([[-1., -1., -1., -1.],
       [-1., -1., -1., -1.],
       [-1., -1., -1., -1.]])

In [16]:

    

dir_deriv(fld2, cell_size_x=10, cell_size_y=10, direct_rad=pi*180.0/180.0)


    

    
Out[16]:





array([[1., 1., 1., 1.],
       [1., 1., 1., 1.],
       [1., 1., 1., 1.]])

In [17]:

    

dir_deriv(fld2, cell_size_x=10, cell_size_y=10, direct_rad=pi*90.0/180.0)


    

    
Out[17]:





array([[-6.123234e-17, -6.123234e-17, -6.123234e-17, -6.123234e-17],
       [-6.123234e-17, -6.123234e-17, -6.123234e-17, -6.123234e-17],
       [-6.123234e-17, -6.123234e-17, -6.123234e-17, -6.123234e-17]])

In [18]:

    

dir_deriv(fld2, cell_size_x=10, cell_size_y=10, direct_rad=pi*270.0/180.0)


    

    
Out[18]:





array([[1.8369702e-16, 1.8369702e-16, 1.8369702e-16, 1.8369702e-16],
       [1.8369702e-16, 1.8369702e-16, 1.8369702e-16, 1.8369702e-16],
       [1.8369702e-16, 1.8369702e-16, 1.8369702e-16, 1.8369702e-16]])

In [19]:

    

dir_deriv(fld2, cell_size_x=10, cell_size_y=10, direct_rad=pi*315.0/180.0)


    

    
Out[19]:





array([[-0.70710678, -0.70710678, -0.70710678, -0.70710678],
       [-0.70710678, -0.70710678, -0.70710678, -0.70710678],
       [-0.70710678, -0.70710678, -0.70710678, -0.70710678]])

In [20]:

    

dir_deriv(fld2, cell_size_x=10, cell_size_y=10, direct_rad=pi*135.0/180.0)


    

    
Out[20]:





array([[0.70710678, 0.70710678, 0.70710678, 0.70710678],
       [0.70710678, 0.70710678, 0.70710678, 0.70710678],
       [0.70710678, 0.70710678, 0.70710678, 0.70710678]])

In [21]:

    

fld3 = array([
   [10, 10, 10, 10],
   [20, 20, 20, 20],
   [30, 30, 30, 30]])


    

In [22]:

    

fld4 = fld3


    

In [23]:

    

orients_d(fld3, fld4)


    

    
Out[23]:





array([[45., 45., 45., 45.],
       [45., 45., 45., 45.],
       [45., 45., 45., 45.]])

In [24]:

    

orients_d(fld3, -fld4)


    

    
Out[24]:





array([[135., 135., 135., 135.],
       [135., 135., 135., 135.],
       [135., 135., 135., 135.]])

In [25]:

    

orients_d(-fld3, fld4)


    

    
Out[25]:





array([[315., 315., 315., 315.],
       [315., 315., 315., 315.],
       [315., 315., 315., 315.]])

In [26]:

    

orients_d(-fld3, -fld4)


    

    
Out[26]:





array([[225., 225., 225., 225.],
       [225., 225., 225., 225.],
       [225., 225., 225., 225.]])

In [27]:

    

orients_d(fld3, 0.0)


    

    
Out[27]:





array([[90., 90., 90., 90.],
       [90., 90., 90., 90.],
       [90., 90., 90., 90.]])

In [28]:

    

orients_d(0, fld4)


    

    
Out[28]:





array([[0., 0., 0., 0.],
       [0., 0., 0., 0.],
       [0., 0., 0., 0.]])

In [29]:

    

orients_d(0, -fld4)


    

    
Out[29]:





array([[180., 180., 180., 180.],
       [180., 180., 180., 180.],
       [180., 180., 180., 180.]])

In [30]:

    

orients_d(-fld3, 0.0)


    

    
Out[30]:





array([[270., 270., 270., 270.],
       [270., 270., 270., 270.],
       [270., 270., 270., 270.]])