sheetjs/README.md

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# xlsx
Parser and writer for various spreadsheet formats. Pure-JS cleanroom
implementation from official specifications, related documents, and test files.
Emphasis on parsing and writing robustness, cross-format feature compatibility
with a unified JS representation, and ES3/ES5 browser compatibility back to IE6.
[**In-Browser Demo**](http://oss.sheetjs.com/js-xlsx)
[**Source Code**](http://git.io/xlsx)
[**Commercial Support**](http://sheetjs.com/reinforcements)
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[**File format support for known spreadsheet data formats:**](#file-formats)
![circo graph of format support](formats.png)
![graph legend](legend.png)
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## Table of Contents
<!-- toc -->
- [Installation](#installation)
* [JS Ecosystem Demos](#js-ecosystem-demos)
* [Optional Modules](#optional-modules)
* [ECMAScript 5 Compatibility](#ecmascript-5-compatibility)
- [Parsing Workbooks](#parsing-workbooks)
- [Working with the Workbook](#working-with-the-workbook)
- [Writing Workbooks](#writing-workbooks)
- [Interface](#interface)
* [Parsing functions](#parsing-functions)
* [Writing functions](#writing-functions)
* [Utilities](#utilities)
- [Common Spreadsheet Format](#common-spreadsheet-format)
* [General Structures](#general-structures)
* [Cell Object](#cell-object)
+ [Data Types](#data-types)
+ [Dates](#dates)
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* [Sheet Objects](#sheet-objects)
+ [Worksheet Object](#worksheet-object)
+ [Chartsheet Object](#chartsheet-object)
* [Workbook Object](#workbook-object)
+ [Workbook File Properties](#workbook-file-properties)
* [Document Features](#document-features)
+ [Formulae](#formulae)
+ [Column Properties](#column-properties)
+ [Hyperlinks](#hyperlinks)
+ [Cell Comments](#cell-comments)
+ [Sheet Visibility](#sheet-visibility)
- [Parsing Options](#parsing-options)
* [Input Type](#input-type)
* [Guessing File Type](#guessing-file-type)
- [Writing Options](#writing-options)
* [Supported Output Formats](#supported-output-formats)
* [Output Type](#output-type)
- [Utility Functions](#utility-functions)
* [Array of Arrays Input](#array-of-arrays-input)
* [HTML Table Input](#html-table-input)
* [Formulae Output](#formulae-output)
* [Delimiter-Separated Output](#delimiter-separated-output)
+ [UTF-16 Unicode Text](#utf-16-unicode-text)
* [JSON](#json)
- [File Formats](#file-formats)
* [Excel 2007+ XML (XLSX/XLSM)](#excel-2007-xml-xlsxxlsm)
* [Excel 2.0-95 (BIFF2/BIFF3/BIFF4/BIFF5)](#excel-20-95-biff2biff3biff4biff5)
* [Excel 97-2004 Binary (BIFF8)](#excel-97-2004-binary-biff8)
* [Excel 2003-2004 (SpreadsheetML)](#excel-2003-2004-spreadsheetml)
* [Excel 2007+ Binary (XLSB, BIFF12)](#excel-2007-binary-xlsb-biff12)
* [OpenDocument Spreadsheet (ODS/FODS)](#opendocument-spreadsheet-odsfods)
+ [Uniform Office Spreadsheet (UOS1/2)](#uniform-office-spreadsheet-uos12)
* [Delimiter-Separated Values (CSV/TXT)](#delimiter-separated-values-csvtxt)
* [Other Single-Worksheet Formats](#other-single-worksheet-formats)
+ [dBASE and Visual FoxPro (DBF)](#dbase-and-visual-foxpro-dbf)
+ [Symbolic Link (SYLK)](#symbolic-link-sylk)
+ [Lotus Formatted Text (PRN)](#lotus-formatted-text-prn)
+ [Data Interchange Format (DIF)](#data-interchange-format-dif)
+ [HTML](#html)
- [Testing](#testing)
* [Tested Environments](#tested-environments)
* [Test Files](#test-files)
- [Contributing](#contributing)
- [License](#license)
- [References](#references)
- [Badges](#badges)
<!-- tocstop -->
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## Installation
With [npm](https://www.npmjs.org/package/xlsx):
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```bash
$ npm install xlsx
```
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In the browser:
```html
<script lang="javascript" src="dist/xlsx.core.min.js"></script>
```
With [bower](http://bower.io/search/?q=js-xlsx):
```bash
$ bower install js-xlsx
```
CDNjs automatically pulls the latest version and makes all versions available at
<http://cdnjs.com/libraries/xlsx>
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### JS Ecosystem Demos
The `demos` directory includes sample projects for:
- [`angular`](demos/angular/)
- [`browserify`](demos/browserify/)
- [`Adobe ExtendScript`](demos/extendscript/)
- [`phantomjs`](demos/phantomjs/)
- [`requirejs`](demos/requirejs/)
- [`systemjs`](demos/systemjs/)
- [`webpack`](demos/webpack/)
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### Optional Modules
The node version automatically requires modules for additional features. Some
of these modules are rather large in size and are only needed in special
circumstances, so they do not ship with the core. For browser use, they must
be included directly:
```html
<!-- international support from js-codepage -->
<script src="dist/cpexcel.js"></script>
```
An appropriate version for each dependency is included in the dist/ directory.
The complete single-file version is generated at `dist/xlsx.full.min.js`
Webpack and browserify builds include optional modules by default. Webpack can
be configured to remove support with `resolve.alias`:
```js
/* uncomment the lines below to remove support */
resolve: {
alias: { "./dist/cpexcel.js": "" } // <-- omit international support
}
```
### ECMAScript 5 Compatibility
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Since xlsx.js uses ES5 functions like `Array#forEach`, older browsers require
[Polyfills](http://git.io/QVh77g). This repo and the gh-pages branch include
[a shim](https://github.com/SheetJS/js-xlsx/blob/master/shim.js)
To use the shim, add the shim before the script tag that loads xlsx.js:
```html
<script type="text/javascript" src="/path/to/shim.js"></script>
```
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## Parsing Workbooks
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For parsing, the first step is to read the file. This involves acquiring the
data and feeding it into the library. Here are a few common scenarios:
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- node readFile:
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```js
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if(typeof require !== 'undefined') XLSX = require('xlsx');
var workbook = XLSX.readFile('test.xlsx');
/* DO SOMETHING WITH workbook HERE */
```
- Browser DOM Table element:
```js
var worksheet = XLSX.utils.table_to_book(document.getElementById('tableau'));
/* DO SOMETHING WITH workbook HERE */
```
- ajax (for a more complete example that works in older browsers, check the demo
at <http://oss.sheetjs.com/js-xlsx/ajax.html>):
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```js
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/* set up XMLHttpRequest */
var url = "test_files/formula_stress_test_ajax.xlsx";
var oReq = new XMLHttpRequest();
oReq.open("GET", url, true);
oReq.responseType = "arraybuffer";
oReq.onload = function(e) {
var arraybuffer = oReq.response;
/* convert data to binary string */
var data = new Uint8Array(arraybuffer);
var arr = new Array();
for(var i = 0; i != data.length; ++i) arr[i] = String.fromCharCode(data[i]);
var bstr = arr.join("");
/* Call XLSX */
var workbook = XLSX.read(bstr, {type:"binary"});
/* DO SOMETHING WITH workbook HERE */
}
oReq.send();
```
- HTML5 drag-and-drop using readAsBinaryString or readAsArrayBuffer:
note: readAsBinaryString and readAsArrayBuffer may not be available in every
browser. Use dynamic feature tests to determine which method to use.
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```js
/* processing array buffers, only required for readAsArrayBuffer */
function fixdata(data) {
var o = "", l = 0, w = 10240;
for(; l<data.byteLength/w; ++l) o+=String.fromCharCode.apply(null,new Uint8Array(data.slice(l*w,l*w+w)));
o+=String.fromCharCode.apply(null, new Uint8Array(data.slice(l*w)));
return o;
}
var rABS = true; // true: readAsBinaryString ; false: readAsArrayBuffer
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/* set up drag-and-drop event */
function handleDrop(e) {
e.stopPropagation();
e.preventDefault();
var files = e.dataTransfer.files;
var i,f;
for (i = 0; i != files.length; ++i) {
f = files[i];
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var reader = new FileReader();
var name = f.name;
reader.onload = function(e) {
var data = e.target.result;
var workbook;
if(rABS) {
/* if binary string, read with type 'binary' */
workbook = XLSX.read(data, {type: 'binary'});
} else {
/* if array buffer, convert to base64 */
var arr = fixdata(data);
workbook = XLSX.read(btoa(arr), {type: 'base64'});
}
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/* DO SOMETHING WITH workbook HERE */
};
if(rABS) reader.readAsBinaryString(f);
else reader.readAsArrayBuffer(f);
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}
}
drop_dom_element.addEventListener('drop', handleDrop, false);
```
- HTML5 input file element using readAsBinaryString or readAsArrayBuffer:
```js
/* fixdata and rABS are defined in the drag and drop example */
function handleFile(e) {
var files = e.target.files;
var i,f;
for (i = 0; i != files.length; ++i) {
f = files[i];
var reader = new FileReader();
var name = f.name;
reader.onload = function(e) {
var data = e.target.result;
var workbook;
if(rABS) {
/* if binary string, read with type 'binary' */
workbook = XLSX.read(data, {type: 'binary'});
} else {
/* if array buffer, convert to base64 */
var arr = fixdata(data);
workbook = XLSX.read(btoa(arr), {type: 'base64'});
}
/* DO SOMETHING WITH workbook HERE */
};
reader.readAsBinaryString(f);
}
}
input_dom_element.addEventListener('change', handleFile, false);
```
## Working with the Workbook
The full object format is described later in this README.
This example extracts the value stored in cell A1 from the first worksheet:
```js
var first_sheet_name = workbook.SheetNames[0];
var address_of_cell = 'A1';
/* Get worksheet */
var worksheet = workbook.Sheets[first_sheet_name];
/* Find desired cell */
var desired_cell = worksheet[address_of_cell];
/* Get the value */
var desired_value = (desired_cell ? desired_cell.v : undefined);
```
**Complete examples:**
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- <http://oss.sheetjs.com/js-xlsx/> HTML5 File API / Base64 Text / Web Workers
Note that older versions of IE do not support HTML5 File API, so the base64 mode
is used for testing. On OSX you can get the base64 encoding with:
```bash
$ <target_file base64 | pbcopy
```
On Windows XP and up you can get the base64 encoding using `certutil`:
```cmd
> certutil -encode target_file target_file.b64
```
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(note: You have to open the file and remove the header and footer lines)
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- <http://oss.sheetjs.com/js-xlsx/ajax.html> XMLHttpRequest
- <https://github.com/SheetJS/js-xlsx/blob/master/bin/xlsx.njs> node
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The node version installs a command line tool `xlsx` which can read spreadsheet
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files and output the contents in various formats. The source is available at
`xlsx.njs` in the bin directory.
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Some helper functions in `XLSX.utils` generate different views of the sheets:
- `XLSX.utils.sheet_to_csv` generates CSV
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- `XLSX.utils.sheet_to_json` generates an array of objects
- `XLSX.utils.sheet_to_formulae` generates a list of formulae
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## Writing Workbooks
For writing, the first step is to generate output data. The helper functions
`write` and `writeFile` will produce the data in various formats suitable for
dissemination. The second step is to actual share the data with the end point.
Assuming `workbook` is a workbook object:
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- nodejs write to file:
```js
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/* output format determined by filename */
XLSX.writeFile(workbook, 'out.xlsx');
/* at this point, out.xlsx is a file that you can distribute */
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```
- browser generate binary blob and "download" to client
(using [FileSaver.js](https://github.com/eligrey/FileSaver.js/) for download):
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```js
/* bookType can be 'xlsx' or 'xlsm' or 'xlsb' or 'ods' */
var wopts = { bookType:'xlsx', bookSST:false, type:'binary' };
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var wbout = XLSX.write(workbook,wopts);
function s2ab(s) {
var buf = new ArrayBuffer(s.length);
var view = new Uint8Array(buf);
for (var i=0; i!=s.length; ++i) view[i] = s.charCodeAt(i) & 0xFF;
return buf;
}
/* the saveAs call downloads a file on the local machine */
saveAs(new Blob([s2ab(wbout)],{type:"application/octet-stream"}), "test.xlsx");
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```
**Complete examples:**
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- <http://sheetjs.com/demos/writexlsx.html> generates a simple file
- <http://git.io/WEK88Q> writing an array of arrays in nodejs
- <http://sheetjs.com/demos/table.html> exporting an HTML table
## Interface
`XLSX` is the exposed variable in the browser and the exported node variable
`XLSX.version` is the version of the library (added by the build script).
`XLSX.SSF` is an embedded version of the [format library](http://git.io/ssf).
### Parsing functions
`XLSX.read(data, read_opts)` attempts to parse `data`.
`XLSX.readFile(filename, read_opts)` attempts to read `filename` and parse.
Parse options are described in the [Parsing Options](#parsing-options) section.
### Writing functions
`XLSX.write(wb, write_opts)` attempts to write the workbook `wb`
`XLSX.writeFile(wb, filename, write_opts)` attempts to write `wb` to `filename`
`XLSX.writeFileAsync(filename, wb, o, cb)` attempts to write `wb` to `filename`.
If `o` is omitted, the writer will use the third argument as the callback.
Write options are described in the [Writing Options](#writing-options) section.
### Utilities
Utilities are available in the `XLSX.utils` object:
**Importing:**
- `aoa_to_sheet` converts an array of arrays of JS data to a worksheet.
**Exporting:**
- `sheet_to_json` converts a worksheet object to an array of JSON objects.
`sheet_to_row_object_array` is an alias that will be removed in the future.
- `sheet_to_csv` generates delimiter-separated-values output.
- `sheet_to_formulae` generates a list of the formulae (with value fallbacks).
Exporters are described in the [Utility Functions](#utility-functions) section.
**Cell and cell address manipulation:**
- `format_cell` generates the text value for a cell (using number formats)
- `{en,de}code_{row,col}` convert between 0-indexed rows/cols and A1 forms.
- `{en,de}code_cell` converts cell addresses
- `{en,de}code_range` converts cell ranges
## Common Spreadsheet Format
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js-xlsx conforms to the Common Spreadsheet Format (CSF):
### General Structures
Cell address objects are stored as `{c:C, r:R}` where `C` and `R` are 0-indexed
column and row numbers, respectively. For example, the cell address `B5` is
represented by the object `{c:1, r:4}`.
Cell range objects are stored as `{s:S, e:E}` where `S` is the first cell and
`E` is the last cell in the range. The ranges are inclusive. For example, the
range `A3:B7` is represented by the object `{s:{c:0, r:2}, e:{c:1, r:6}}`. Utils
use the following pattern to walk each of the cells in a range:
```js
for(var R = range.s.r; R <= range.e.r; ++R) {
for(var C = range.s.c; C <= range.e.c; ++C) {
var cell_address = {c:C, r:R};
}
}
```
### Cell Object
| Key | Description |
| --- | ---------------------------------------------------------------------- |
| `v` | raw value (see Data Types section for more info) |
| `w` | formatted text (if applicable) |
| `t` | cell type: `b` Boolean, `n` Number, `e` error, `s` String, `d` Date |
| `f` | cell formula encoded as an A1-style string (if applicable) |
| `F` | range of enclosing array if formula is array formula (if applicable) |
| `r` | rich text encoding (if applicable) |
| `h` | HTML rendering of the rich text (if applicable) |
| `c` | comments associated with the cell |
| `z` | number format string associated with the cell (if requested) |
| `l` | cell hyperlink object (.Target holds link, .Tooltip is tooltip) |
| `s` | the style/theme of the cell (if applicable) |
Built-in export utilities (such as the CSV exporter) will use the `w` text if it
is available. To change a value, be sure to delete `cell.w` (or set it to
`undefined`) before attempting to export. The utilities will regenerate the `w`
text from the number format (`cell.z`) and the raw value if possible.
The actual array formula is stored in the `f` field of the first cell in the
array range. Other cells in the range will omit the `f` field.
#### Data Types
The raw value is stored in the `v` field, interpreted based on the `t` field.
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Type `b` is the Boolean type. `v` is interpreted according to JS truth tables.
Type `e` is the Error type. `v` holds the number and `w` holds the common name:
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| Value | Error Meaning |
| -----: | :-------------- |
| `0x00` | `#NULL!` |
| `0x07` | `#DIV/0!` |
| `0x0F` | `#VALUE!` |
| `0x17` | `#REF!` |
| `0x1D` | `#NAME?` |
| `0x24` | `#NUM!` |
| `0x2A` | `#N/A` |
| `0x2B` | `#GETTING_DATA` |
Type `n` is the Number type. This includes all forms of data that Excel stores
as numbers, such as dates/times and Boolean fields. Excel exclusively uses data
that can be fit in an IEEE754 floating point number, just like JS Number, so the
`v` field holds the raw number. The `w` field holds formatted text. Dates are
stored as numbers by default and converted with `XLSX.SSF.parse_date_code`.
Type `d` is the Date type, generated only when the option `cellDates` is passed.
Since JSON does not have a natural Date type, parsers are generally expected to
store ISO 8601 Date strings like you would get from `date.toISOString()`. On
the other hand, writers and exporters should be able to handle date strings and
JS Date objects. Note that Excel disregards timezone modifiers and treats all
dates in the local timezone. js-xlsx does not correct for this error.
Type `s` is the String type. `v` should be explicitly stored as a string to
avoid possible confusion.
Type `z` represents blank stub cells. These do not have any data or type, and
are not processed by any of the core library functions. By default these cells
will not be generated; the parser `sheetStubs` option must be set to `true`.
#### Dates
By default, Excel stores dates as numbers with a format code that specifies date
processing. For example, the date `19-Feb-17` is stored as the number `42785`
with a number format of `d-mmm-yy`. The `SSF` module understands number formats
and performs the appropriate conversion.
XLSX also supports a special date type `d` where the data is an ISO 8601 date
string. The formatter converts the date back to a number.
The default behavior for all parsers is to generate number cells. Setting
`cellDates` to true will force the generators to store dates.
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### Sheet Objects
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Each key that does not start with `!` maps to a cell (using `A-1` notation)
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`sheet[address]` returns the cell object for the specified address.
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Special sheet keys (accessible as `sheet[key]`, each starting with `!`):
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- `sheet['!ref']`: A-1 based range representing the sheet range. Functions that
work with sheets should use this parameter to determine the range. Cells that
are assigned outside of the range are not processed. In particular, when
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writing a sheet by hand, cells outside of the range are not included
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Functions that handle sheets should test for the presence of `!ref` field.
If the `!ref` is omitted or is not a valid range, functions are free to treat
the sheet as empty or attempt to guess the range. The standard utilities that
ship with this library treat sheets as empty (for example, the CSV output is
empty string).
When reading a worksheet with the `sheetRows` property set, the ref parameter
will use the restricted range. The original range is set at `ws['!fullref']`
#### Worksheet Object
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In addition to the base sheet keys, worksheets also add:
- `ws['!cols']`: array of column properties objects. Column widths are actually
stored in files in a normalized manner, measured in terms of the "Maximum
Digit Width" (the largest width of the rendered digits 0-9, in pixels). When
parsed, the column objects store the pixel width in the `wpx` field, character
width in the `wch` field, and the maximum digit width in the `MDW` field.
- `ws['!merges']`: array of range objects corresponding to the merged cells in
the worksheet. Plaintext utilities are unaware of merge cells. CSV export
will write all cells in the merge range if they exist, so be sure that only
the first cell (upper-left) in the range is set.
#### Chartsheet Object
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Chartsheets are represented as standard sheets. They are distinguished with the
`!type` property set to `"chart"`.
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The underlying data and `!ref` refer to the cached data in the chartsheet. The
first row of the chartsheet is the underlying header.
### Workbook Object
`workbook.SheetNames` is an ordered list of the sheets in the workbook
`wb.Sheets[sheetname]` returns an object representing the worksheet.
`wb.Props` is an object storing the standard properties. `wb.Custprops` stores
custom properties. Since the XLS standard properties deviate from the XLSX
standard, XLS parsing stores core properties in both places.
`wb.WBProps` includes more workbook-level properties:
- Excel supports two epochs (January 1 1900 and January 1 1904), see
[1900 vs. 1904 Date System](http://support2.microsoft.com/kb/180162).
The workbook's epoch can be determined by examining the workbook's
`wb.WBProps.date1904` property.
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#### Workbook File Properties
The various file formats use different internal names for file properties. The
workbook `Props` object normalizes the names:
| JS Name | Excel Description |
|:------------|:-------------------------------|
| Title | Summary tab "Title" |
| Subject | Summary tab "Subject" |
| Author | Summary tab "Author" |
| Manager | Summary tab "Manager" |
| Company | Summary tab "Company" |
| Category | Summary tab "Category" |
| Keywords | Summary tab "Keywords" |
| Comments | Summary tab "Comments" |
| LastAuthor | Statistics tab "Last saved by" |
| CreatedDate | Statistics tab "Created" |
For example, to set the workbook title property:
```js
if(!wb.Props) wb.Props = {};
wb.Props.Title = "Insert Title Here";
```
Custom properties are added in the workbook `Custprops` object:
```js
if(!wb.Custprops) wb.Custprops = {};
wb.Custprops["Custom Property"] = "Custom Value";
```
### Document Features
Even for basic features like date storage, the official Excel formats store the
same content in different ways. The parsers are expected to convert from the
underlying file format representation to the Common Spreadsheet Format. Writers
are expected to convert from CSF back to the underlying file format.
#### Formulae
The A1-style formula string is stored in the `f` field. Even though different
file formats store the formulae in different ways, the formats are translated.
Even though some formats store formulae with a leading equal sign, CSF formulae
do not start with `=`.
The worksheet representation of A1=1, A2=2, A3=A1+A2:
```js
{
"!ref": "A1:A3",
A1: { t:'n', v:1 },
A2: { t:'n', v:2 },
A3: { t:'n', v:3, f:'A1+A2' }
}
```
Shared formulae are decompressed and each cell has the formula corresponding to
its cell. Writers generally do not attempt to generate shared formulae.
Cells with formula entries but no value will be serialized in a way that Excel
and other spreadsheet tools will recognize. This library will not automatically
compute formula results! For example, to compute `BESSELJ` in a worksheet:
```js
{
"!ref": "A1:A3",
A1: { t:'n', v:3.14159 },
A2: { t:'n', v:2 },
A3: { t:'n', f:'BESSELJ(A1,A2)' }
}
```
**Array Formulae**
Array formulae are stored in the top-left cell of the array block. All cells
of an array formula have a `F` field corresponding to the range. A single-cell
formula can be distinguished from a plain formula by the presence of `F` field.
For example, setting the cell `C1` to the array formula `{=SUM(A1:A3*B1:B3)}`:
```js
worksheet['C1'] = { t:'n', f: "SUM(A1:A3*B1:B3)", F:"C1:C1" };
```
For a multi-cell array formula, every cell has the same array range but only the
first cell has content. Consider `D1:D3=A1:A3*B1:B3`:
```js
worksheet['D1'] = { t:'n', F:"D1:D3", f:"A1:A3*B1:B3" };
worksheet['D2'] = { t:'n', F:"D1:D3" };
worksheet['D3'] = { t:'n', F:"D1:D3" };
```
Utilities and writers are expected to check for the presence of a `F` field and
ignore any possible formula element `f` in cells other than the starting cell.
They are not expected to perform validation of the formulae!
**Formula Output**