Shaping and slicing numpy arrays

wk-03-03-shaping and slicing

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     "input": [
      "import numpy as np\n",
      "myarray = np.reshape(np.arange(16),(4,4))\n",
      "\n",
      "# Accessing specific part of matrix a\n",
      "# a. Four elements in the north-west corner\n",
      "# b. Four elements in the middle\n",
      "# c. Four elements in the south-east corner\n",
      "\n",
      "a = myarray[0:2,0:2]\n",
      "b = myarray[1:3,1:3]\n",
      "c = myarray[2:,2:]\n",
      "\n",
      "print 'a'\n",
      "print a\n",
      "print 'b'\n",
      "print b\n",
      "print 'c'\n",
      "print c\n"
     ],
     "language": "python",
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     "cell_type": "code",
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     "input": [
      "# Create a 4x3 array\n",
      "# Obtain the sum of each row\n",
      "# Obtain the sum of each column\n",
      "\n",
      "a = np.reshape(np.arange(9),(3,3))\n",
      "\n",
      "# for row sums\n",
      "for r in range(a.shape[0]):\n",
      "\tprint sum(a[r,:])\n",
      "\n",
      "    # for column sums\n",
      "for r in range(a.shape[1]):\n",
      "\tprint sum(a[:,r])\n"
     ],
     "language": "python",
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     "outputs": []
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