feat: xlsx subtable extraction (#1585)

**Executive Summary**
Unstructured is now able to capture subtables, along with other text
element types within the `.xlsx` sheet.

**Technical Details**
- The function now reads the excel *without* header as default
- Leverages the connected components search to find subtables within the
sheet. This search is based on dfs search
- It also handle the overlapping table or text cases
- Row with only single cell of data is considered not a table, and
therefore passed on the determine the element type as text
- In connected elements, it is possible to have table title, header, or
footer. We run the count for the first non-single empty rows from top
and bottom to determine those text

**Result**
This table now reads as:
<img width="747" alt="image"
src="https://github.com/Unstructured-IO/unstructured/assets/2177850/6b8e6d01-4ca5-43f4-ae88-6104b0174ed2">

```
[
    {
        "type": "Title",
        "element_id": "3315afd97f7f2ebcd450e7c939878429",
        "metadata": {
            "filename": "vodafone.xlsx",
            "file_directory": "example-docs",
            "last_modified": "2023-10-03T17:51:34",
            "filetype": "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
            "parent_id": "3315afd97f7f2ebcd450e7c939878429",
            "languages": [
                "spa",
                "ita"
            ],
            "page_number": 1,
            "page_name": "Index",
            "text_as_html": "<table border=\"1\" class=\"dataframe\">\n  <tbody>\n    <tr>\n      <td>Topic</td>\n      <td>Period</td>\n      <td></td>\n      <td></td>\n      <td>Page</td>\n    </tr>\n    <tr>\n      <td>Quarterly revenue</td>\n      <td>Nine quarters to 30 June 2023</td>\n      <td></td>\n      <td></td>\n      <td>1</td>\n    </tr>\n    <tr>\n      <td>Group financial performance</td>\n      <td>FY 22</td>\n      <td>FY 23</td>\n      <td></td>\n      <td>2</td>\n    </tr>\n    <tr>\n      <td>Segmental results</td>\n      <td>FY 22</td>\n      <td>FY 23</td>\n      <td></td>\n      <td>3</td>\n    </tr>\n    <tr>\n      <td>Segmental analysis</td>\n      <td>FY 22</td>\n      <td>FY 23</td>\n      <td></td>\n      <td>4</td>\n    </tr>\n    <tr>\n      <td>Cash flow</td>\n      <td>FY 22</td>\n      <td>FY 23</td>\n      <td></td>\n      <td>5</td>\n    </tr>\n  </tbody>\n</table>"
        },
        "text": "Financial performance"
    },
    {
        "type": "Table",
        "element_id": "17f5d512705be6f8812e5dbb801ba727",
        "metadata": {
            "filename": "vodafone.xlsx",
            "file_directory": "example-docs",
            "last_modified": "2023-10-03T17:51:34",
            "filetype": "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
            "parent_id": "3315afd97f7f2ebcd450e7c939878429",
            "languages": [
                "spa",
                "ita"
            ],
            "page_number": 1,
            "page_name": "Index",
            "text_as_html": "<table border=\"1\" class=\"dataframe\">\n  <tbody>\n    <tr>\n      <td>Topic</td>\n      <td>Period</td>\n      <td></td>\n      <td></td>\n      <td>Page</td>\n    </tr>\n    <tr>\n      <td>Quarterly revenue</td>\n      <td>Nine quarters to 30 June 2023</td>\n      <td></td>\n      <td></td>\n      <td>1</td>\n    </tr>\n    <tr>\n      <td>Group financial performance</td>\n      <td>FY 22</td>\n      <td>FY 23</td>\n      <td></td>\n      <td>2</td>\n    </tr>\n    <tr>\n      <td>Segmental results</td>\n      <td>FY 22</td>\n      <td>FY 23</td>\n      <td></td>\n      <td>3</td>\n    </tr>\n    <tr>\n      <td>Segmental analysis</td>\n      <td>FY 22</td>\n      <td>FY 23</td>\n      <td></td>\n      <td>4</td>\n    </tr>\n    <tr>\n      <td>Cash flow</td>\n      <td>FY 22</td>\n      <td>FY 23</td>\n      <td></td>\n      <td>5</td>\n    </tr>\n  </tbody>\n</table>"
        },
        "text": "\n\n\nTopic\nPeriod\n\n\nPage\n\n\nQuarterly revenue\nNine quarters to 30 June 2023\n\n\n1\n\n\nGroup financial performance\nFY 22\nFY 23\n\n2\n\n\nSegmental results\nFY 22\nFY 23\n\n3\n\n\nSegmental analysis\nFY 22\nFY 23\n\n4\n\n\nCash flow\nFY 22\nFY 23\n\n5\n\n\n"
    },
    {
        "type": "Title",
        "element_id": "8a9db7161a02b427f8fda883656036e1",
        "metadata": {
            "filename": "vodafone.xlsx",
            "file_directory": "example-docs",
            "last_modified": "2023-10-03T17:51:34",
            "filetype": "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
            "parent_id": "8a9db7161a02b427f8fda883656036e1",
            "languages": [
                "spa",
                "ita"
            ],
            "page_number": 1,
            "page_name": "Index",
            "text_as_html": "<table border=\"1\" class=\"dataframe\">\n  <tbody>\n    <tr>\n      <td>Topic</td>\n      <td>Period</td>\n      <td></td>\n      <td></td>\n      <td>Page</td>\n    </tr>\n    <tr>\n      <td>Mobile customers</td>\n      <td>Nine quarters to 30 June 2023</td>\n      <td></td>\n      <td></td>\n      <td>6</td>\n    </tr>\n    <tr>\n      <td>Fixed broadband customers</td>\n      <td>Nine quarters to 30 June 2023</td>\n      <td></td>\n      <td></td>\n      <td>7</td>\n    </tr>\n    <tr>\n      <td>Marketable homes passed</td>\n      <td>Nine quarters to 30 June 2023</td>\n      <td></td>\n      <td></td>\n      <td>8</td>\n    </tr>\n    <tr>\n      <td>TV customers</td>\n      <td>Nine quarters to 30 June 2023</td>\n      <td></td>\n      <td></td>\n      <td>9</td>\n    </tr>\n    <tr>\n      <td>Converged customers</td>\n      <td>Nine quarters to 30 June 2023</td>\n      <td></td>\n      <td></td>\n      <td>10</td>\n    </tr>\n    <tr>\n      <td>Mobile churn</td>\n      <td>Nine quarters to 30 June 2023</td>\n      <td></td>\n      <td></td>\n      <td>11</td>\n    </tr>\n    <tr>\n      <td>Mobile data usage</td>\n      <td>Nine quarters to 30 June 2023</td>\n      <td></td>\n      <td></td>\n      <td>12</td>\n    </tr>\n    <tr>\n      <td>Mobile ARPU</td>\n      <td>Nine quarters to 30 June 2023</td>\n      <td></td>\n      <td></td>\n      <td>13</td>\n    </tr>\n  </tbody>\n</table>"
        },
        "text": "Operational metrics"
    },
    {
        "type": "Table",
        "element_id": "d5d16f7bf9c7950cd45fae06e12e5847",
        "metadata": {
            "filename": "vodafone.xlsx",
            "file_directory": "example-docs",
            "last_modified": "2023-10-03T17:51:34",
            "filetype": "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
            "parent_id": "8a9db7161a02b427f8fda883656036e1",
            "languages": [
                "spa",
                "ita"
            ],
            "page_number": 1,
            "page_name": "Index",
            "text_as_html": "<table border=\"1\" class=\"dataframe\">\n  <tbody>\n    <tr>\n      <td>Topic</td>\n      <td>Period</td>\n      <td></td>\n      <td></td>\n      <td>Page</td>\n    </tr>\n    <tr>\n      <td>Mobile customers</td>\n      <td>Nine quarters to 30 June 2023</td>\n      <td></td>\n      <td></td>\n      <td>6</td>\n    </tr>\n    <tr>\n      <td>Fixed broadband customers</td>\n      <td>Nine quarters to 30 June 2023</td>\n      <td></td>\n      <td></td>\n      <td>7</td>\n    </tr>\n    <tr>\n      <td>Marketable homes passed</td>\n      <td>Nine quarters to 30 June 2023</td>\n      <td></td>\n      <td></td>\n      <td>8</td>\n    </tr>\n    <tr>\n      <td>TV customers</td>\n      <td>Nine quarters to 30 June 2023</td>\n      <td></td>\n      <td></td>\n      <td>9</td>\n    </tr>\n    <tr>\n      <td>Converged customers</td>\n      <td>Nine quarters to 30 June 2023</td>\n      <td></td>\n      <td></td>\n      <td>10</td>\n    </tr>\n    <tr>\n      <td>Mobile churn</td>\n      <td>Nine quarters to 30 June 2023</td>\n      <td></td>\n      <td></td>\n      <td>11</td>\n    </tr>\n    <tr>\n      <td>Mobile data usage</td>\n      <td>Nine quarters to 30 June 2023</td>\n      <td></td>\n      <td></td>\n      <td>12</td>\n    </tr>\n    <tr>\n      <td>Mobile ARPU</td>\n      <td>Nine quarters to 30 June 2023</td>\n      <td></td>\n      <td></td>\n      <td>13</td>\n    </tr>\n  </tbody>\n</table>"
        },
        "text": "\n\n\nTopic\nPeriod\n\n\nPage\n\n\nMobile customers\nNine quarters to 30 June 2023\n\n\n6\n\n\nFixed broadband customers\nNine quarters to 30 June 2023\n\n\n7\n\n\nMarketable homes passed\nNine quarters to 30 June 2023\n\n\n8\n\n\nTV customers\nNine quarters to 30 June 2023\n\n\n9\n\n\nConverged customers\nNine quarters to 30 June 2023\n\n\n10\n\n\nMobile churn\nNine quarters to 30 June 2023\n\n\n11\n\n\nMobile data usage\nNine quarters to 30 June 2023\n\n\n12\n\n\nMobile ARPU\nNine quarters to 30 June 2023\n\n\n13\n\n\n"
    },
    {
        "type": "Title",
        "element_id": "f97e9da0e3b879f0a9df979ae260a5f7",
        "metadata": {
            "filename": "vodafone.xlsx",
            "file_directory": "example-docs",
            "last_modified": "2023-10-03T17:51:34",
            "filetype": "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
            "parent_id": "f97e9da0e3b879f0a9df979ae260a5f7",
            "languages": [
                "spa",
                "ita"
            ],
            "page_number": 1,
            "page_name": "Index",
            "text_as_html": "<table border=\"1\" class=\"dataframe\">\n  <tbody>\n    <tr>\n      <td>Topic</td>\n      <td>Period</td>\n      <td></td>\n      <td></td>\n      <td>Page</td>\n    </tr>\n    <tr>\n      <td>Average foreign exchange rates</td>\n      <td>Nine quarters to 30 June 2023</td>\n      <td></td>\n      <td></td>\n      <td>14</td>\n    </tr>\n    <tr>\n      <td>Guidance rates</td>\n      <td>FY 23/24</td>\n      <td></td>\n      <td></td>\n      <td>14</td>\n    </tr>\n  </tbody>\n</table>"
        },
        "text": "Other"
    },
    {
        "type": "Table",
        "element_id": "080e1a745a2a3f2df22b6a08d33d59bb",
        "metadata": {
            "filename": "vodafone.xlsx",
            "file_directory": "example-docs",
            "last_modified": "2023-10-03T17:51:34",
            "filetype": "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
            "parent_id": "f97e9da0e3b879f0a9df979ae260a5f7",
            "languages": [
                "spa",
                "ita"
            ],
            "page_number": 1,
            "page_name": "Index",
            "text_as_html": "<table border=\"1\" class=\"dataframe\">\n  <tbody>\n    <tr>\n      <td>Topic</td>\n      <td>Period</td>\n      <td></td>\n      <td></td>\n      <td>Page</td>\n    </tr>\n    <tr>\n      <td>Average foreign exchange rates</td>\n      <td>Nine quarters to 30 June 2023</td>\n      <td></td>\n      <td></td>\n      <td>14</td>\n    </tr>\n    <tr>\n      <td>Guidance rates</td>\n      <td>FY 23/24</td>\n      <td></td>\n      <td></td>\n      <td>14</td>\n    </tr>\n  </tbody>\n</table>"
        },
        "text": "\n\n\nTopic\nPeriod\n\n\nPage\n\n\nAverage foreign exchange rates\nNine quarters to 30 June 2023\n\n\n14\n\n\nGuidance rates\nFY 23/24\n\n\n14\n\n\n"
    }
]
```

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ### Enhancements
 
+* **Adds XLSX document level language detection** Enhancing on top of language detection functionality in previous release, we now support language detection within `.xlsx` file type at Element level.
 * **bump `unstructured-inference` to `0.6.6`** The updated version of `unstructured-inference` makes table extraction in `hi_res` mode configurable to fine tune table extraction performance; it also improves element detection by adding a deduplication post processing step in the `hi_res` partitioning of pdfs and images.
 * **Detect text in HTML Heading Tags as Titles** This will increase the accuracy of hierarchies in HTML documents and provide more accurate element categorization. If text is in an HTML heading tag and is not a list item, address, or narrative text, categorize it as a title.
 * **Update python-based docs** Refactor docs to use the actual unstructured code rather than using the subprocess library to run the cli command itself.
@@ -10,7 +11,7 @@
 * **Expose endpoint url for s3 connectors** By allowing for the endpoint url to be explicitly overwritten, this allows for any non-AWS data providers supporting the s3 protocol to be supported (i.e. minio).
 * **change default `hi_res` model for pdf/image partition to `yolox`** Now partitioning pdf/image using `hi_res` strategy utilizes `yolox_quantized` model isntead of `detectron2_onnx` model. This new default model has better recall for tables and produces more detailed categories for elements.
 
-### Features
+* **XLSX can now reads subtables within one sheet** Problem: Many .xlsx files are not created to be read as one full table per sheet. There are subtables, text and header along with more informations to extract from each sheet. Feature: This `partition_xlsx` now can reads subtable(s) within one .xlsx sheet, along with extracting other title and narrative texts. Importance: This enhance the power of .xlsx reading to not only one table per sheet, allowing user to capture more data tables from the file, if exists.
 
 ### Fixes
 

docs/requirements.txt

@@ -18,7 +18,7 @@ certifi==2023.7.22
     #   -c requirements/constraints.in
     #   -r requirements/build.in
     #   requests
-charset-normalizer==3.2.0
+charset-normalizer==3.3.0
     # via
     #   -c requirements/base.txt
     #   requests
@@ -54,7 +54,7 @@ mdurl==0.1.2
     # via markdown-it-py
 myst-parser==2.0.0
     # via -r requirements/build.in
-packaging==23.1
+packaging==23.2
     # via
     #   -c requirements/base.txt
     #   sphinx

requirements/base.txt

@@ -12,7 +12,7 @@ certifi==2023.7.22
     #   requests
 chardet==5.2.0
     # via -r requirements/base.in
-charset-normalizer==3.2.0
+charset-normalizer==3.3.0
     # via requests
 click==8.1.7
     # via nltk
@@ -40,7 +40,7 @@ numpy==1.24.4
     # via
     #   -c requirements/constraints.in
     #   -r requirements/base.in
-packaging==23.1
+packaging==23.2
     # via marshmallow
 python-iso639==2023.6.15
     # via -r requirements/base.in

requirements/build.txt

@@ -18,7 +18,7 @@ certifi==2023.7.22
     #   -c requirements/constraints.in
     #   -r requirements/build.in
     #   requests
-charset-normalizer==3.2.0
+charset-normalizer==3.3.0
     # via
     #   -c requirements/base.txt
     #   requests
@@ -54,7 +54,7 @@ mdurl==0.1.2
     # via markdown-it-py
 myst-parser==2.0.0
     # via -r requirements/build.in
-packaging==23.1
+packaging==23.2
     # via
     #   -c requirements/base.txt
     #   sphinx