check_rotations.ipynb

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   "cell_type": "code",
   "execution_count": 45,
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   "source": [
    "import numpy as np\n",
    "from numpy import sin, cos\n",
    "import dipy.core.geometry as gm"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 55,
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   "source": [
    "def rotation_matrix(x, y, z):\n",
    "    Rx = np.array([[1, 0, 0], [0, cos(x), sin(x)], [0, -sin(x), cos(x)]])\n",
    "    Ry = np.array([[cos(y), 0, -sin(y)], [0, 1, 0], [sin(y), 0, cos(y)]])\n",
    "    Rz = np.array([[cos(z), sin(z), 0], [-sin(z), cos(z), 0], [0, 0, 1]])\n",
    "    return np.linalg.inv(Rx@Ry@Rz)"
   ]
  },
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   "cell_type": "code",
   "execution_count": 68,
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   "source": [
    "for x in [-np.pi, 0, 10e-30, 1, 2*np.pi]:\n",
    "    for y in [-np.pi, 0, 10e-30, 1, 2*np.pi]:\n",
    "        for z in [-np.pi, 0, 10e-30, 1, 2*np.pi]:\n",
    "            R1 = rotation_matrix(x, y, z)\n",
    "            R2 = gm.euler_matrix(x, y, z)[:3, :3]\n",
    "\n",
    "            assert np.allclose(R1, R2)"
   ]
  },
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   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "collapsed": true
   },
   "outputs": [],
   "source": []
  }
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