Get the number of chunks in an h5py.Dataset

get_num_chunks.ipynb

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   "source": [
    "import math\n",
    "import h5py"
   ]
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   "source": [
    "f = h5py.File(\"/Users/rly/Documents/NWB_Data/GiocomoData_dandiset53/000053/sub-npI1/sub-npI1_ses-20190413_behavior+ecephys.nwb\", \"r\")"
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   "id": "95f6c144-1fc4-4364-954e-249d5e742e09",
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   "outputs": [],
   "source": [
    "data = f[\"/acquisition/ElectricalSeries/data\"]"
   ]
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   "id": "b139cff1-3c05-4f9d-bc16-7d192b390722",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(141969007, 384)"
      ]
     },
     "execution_count": 6,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "data.shape"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "id": "b6abfeb7-5889-4c8e-add8-ffc826701903",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(277284, 1)"
      ]
     },
     "execution_count": 7,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "data.chunks"
   ]
  },
  {
   "cell_type": "code",
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   "id": "7e330610-e679-4cfc-b653-b7d248cea666",
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    {
     "data": {
      "text/plain": [
       "512"
      ]
     },
     "execution_count": 8,
     "metadata": {},
     "output_type": "execute_result"
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   "source": [
    "math.ceil(141969007/277284)"
   ]
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   "cell_type": "code",
   "execution_count": 9,
   "id": "810a02f8-eeef-44c5-88c5-b1e06bb82d27",
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   "outputs": [
    {
     "data": {
      "text/plain": [
       "196608"
      ]
     },
     "execution_count": 9,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "math.ceil(141969007/277284) * 384"
   ]
  },
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   "cell_type": "code",
   "execution_count": 11,
   "id": "b2ade0ac-6f6e-4fd5-b925-67cf8c7bea57",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "196608"
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     },
     "execution_count": 11,
     "metadata": {},
     "output_type": "execute_result"
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   ],
   "source": [
    "data.id.get_num_chunks()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 12,
   "id": "2710c3e9-5aeb-4d68-8202-89d84c2940b9",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "196608"
      ]
     },
     "execution_count": 12,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "math.ceil(data.shape[0]/data.chunks[0]) * math.ceil(data.shape[1]/data.chunks[1])"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "cf06897e-e369-449f-afc6-1042f3e29486",
   "metadata": {},
   "outputs": [],
   "source": [
    "math.ceil(data.shape[0]/data.chunks[0]) * math.ceil(data.shape[1]/data.chunks[1]) * math.ceil(data.shape[2]/data.chunks[2])"
   ]
  }
 ],
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