10_Numpy_Indexing.ipynb

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   "source": [
    "# Numpy Indexing"
   ]
  },
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   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## np.newaxis: Insert a new axis into an array"
   ]
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      "[[1]\n",
      " [2]\n",
      " [3]\n",
      " [4]\n",
      " [5]]\n"
     ]
    }
   ],
   "source": [
    "import numpy as np\n",
    "\n",
    "# Create a 1D array\n",
    "arr = np.array([1, 2, 3, 4, 5])\n",
    "\n",
    "# Insert a new axis to make it a 2D array\n",
    "new_arr = arr[:, np.newaxis]\n",
    "print(new_arr)\n"
   ]
  },
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   "source": [
    "## np.take(): Return elements from an array at specified indices"
   ]
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   "outputs": [
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     "text": [
      "[1 3 5]\n"
     ]
    }
   ],
   "source": [
    "import numpy as np\n",
    "\n",
    "# Create an array\n",
    "arr = np.array([1, 2, 3, 4, 5])\n",
    "\n",
    "# Return elements at specified indices\n",
    "indices = [0, 2, 4]\n",
    "taken_elements = np.take(arr, indices)\n",
    "print(taken_elements)\n"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## np.where(): Return the indices of elements that satisfy a condition"
   ]
  },
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   "outputs": [
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     "text": [
      "(array([3, 4]),)\n"
     ]
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   ],
   "source": [
    "import numpy as np\n",
    "\n",
    "# Create an array\n",
    "arr = np.array([1, 2, 3, 4, 5])\n",
    "\n",
    "# Return the indices of elements greater than 3\n",
    "indices = np.where(arr > 3)\n",
    "print(indices)\n"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## np.argmax(): Find the indices of the maximum value along an axis.\n"
   ]
  },
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   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "[2 2]\n"
     ]
    }
   ],
   "source": [
    "import numpy as np\n",
    "\n",
    "# Create a 2D array\n",
    "arr = np.array([[1, 2, 3], [4, 5, 6]])\n",
    "\n",
    "# Find the indices of the maximum value along the second axis\n",
    "indices = np.argmax(arr, axis=1)\n",
    "print(indices)\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
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