.. _worksheet:

The Worksheet Class
===================

The worksheet class represents an Excel worksheet. It handles operations such
as writing data to cells or formatting worksheet layout.

A worksheet object isn't instantiated directly. Instead a new worksheet is
created by calling the :func:`add_worksheet()` method from a :func:`Workbook`
object::

    workbook   = Workbook('filename.xlsx')

    worksheet1 = workbook.add_worksheet()
    worksheet2 = workbook.add_worksheet()
    
    worksheet1.write('A1', 123)

.. image:: _static/worksheet00.png


worksheet.write()
-----------------

.. py:function:: write(row, col, data[, cell_format])

   Write generic data to a worksheet cell.

   :param row:         The cell row (zero indexed).
   :param col:         The cell column (zero indexed).
   :param data:        Cell data to write. Variable types.
   :param cell_format: Optional Format object.
   :type  row:         integer
   :type  col:         integer
   :type  cell_format: :ref:`Format <format>`

Excel makes a distinction between data types such as strings, numbers, blanks,
formulas and hyperlinks. To simplify the process of writing data to an
XlsxWriter file the ``write()`` method acts as a general alias for several
more specific methods:

* :func:`write_string()`
* :func:`write_number()`
* :func:`write_blank()`
* :func:`write_formula()`

The general rule is that if the data looks like a *something* then a
*something* is written. Here are some examples::


    worksheet.write(0, 0, 'Hello')          # write_string()
    worksheet.write(1, 0, 'World')          # write_string()
    worksheet.write(2, 0, 2)                # write_number()
    worksheet.write(3, 0, 3.00001)          # write_number()
    worksheet.write(4, 0, '=SIN(PI()/4)')   # write_formula()
    worksheet.write(5, 0, '')               # write_blank()
    worksheet.write(6, 0, None)             # write_blank()

This creates a worksheet like the following:

.. image:: _static/worksheet01.png

The ``write()`` method supports two forms of notation to designate the position
of cells: **Row-column** notation and **A1** notation::

    # These are equivalent.
    worksheet.write(0, 0, 'Hello')
    worksheet.write('A1', 'Hello')

See :ref:`cell_notation` for more details.


The ``cell_format`` parameter is used to apply formatting to the cell. This
parameter is optional but when present is should be a valid
:ref:`Format <format>` object::

    cell_format = workbook.add_format({'bold': True, 'italic': True})

    worksheet.write(0, 0, 'Hello', cell_format)  # Cell is bold and italic.

The ``write()`` method will ignore empty strings or ``None`` unless a format is
also supplied. As such you needn't worry about special handling for empty or
``None`` values in your data. See also the :func:`write_blank()` method.


One problem with the ``write()`` method is that occasionally data looks like a
number but you don't want it treated as a number. For example, Zip codes or ID
numbers or often start with a leading zero. If you write this data as a number
then the leading zero(s) will be stripped. In this case you shouldn't use the
``write()`` method and should use ``write_string()`` instead.


worksheet.write_string()
------------------------

.. py:function:: write_string(row, col, string[, cell_format])

   Write a string to a worksheet cell.

   :param row:         The cell row (zero indexed).
   :param col:         The cell column (zero indexed).
   :param string:      String to write to cell.
   :param cell_format: Optional Format object.
   :type  row:         integer
   :type  col:         integer
   :type  string:      string
   :type  cell_format: :ref:`Format <format>`

The ``write_string()`` method writes a string to the cell specified by ``row``
and ``column``::

    worksheet.write_string(0, 0, 'Your text here')
    worksheet.write_string('A2', 'or here')

Both row-column and A1 style notation are support. See :ref:`cell_notation` for
more details.

The ``cell_format`` parameter is used to apply formatting to the cell. This
parameter is optional but when present is should be a valid
:ref:`Format <format>` object.

Unicode strings are supported in UTF-8 encoding. This generally requires that
your source file in also UTF-8 encoded::

    # _*_ coding: utf-8

    worksheet.write('A1', u'Some UTF-8 text')

.. image:: _static/worksheet02.png

Alternatively, you can read data from an encoded file, convert it to UTF-8
during reading and then write the data to an Excel file. There are several
sample
``unicode_*.py`` programs like this in the ``examples`` directory of the XlsxWriter source tree.

The maximum string size supported by Excel is 32,767 characters. Strings longer
than this will be truncated by ``write_string()``.

.. note::
   Even though Excel allows strings of 32,767 characters in a cell, Excel
   can only **display** 1000. All 32,767 characters are displayed in the
   formula bar.

In general it is sufficient to use the ``write()`` method when dealing with
string data. However, you may sometimes need to use ``write_string()`` to
write data that looks like a number but that you don't want treated as a
number. For example, Zip codes or phone numbers::

    # Write ID number as a plain string.
    worksheet.write_string('A1', '01209')

However, if the user edits this string Excel may convert it back to a number.
To get around this you can use the Excel text format ``'@'``::

    # Format as a string. Doesn't change to a number when edited
    str_format = workbook.add_format({'num_format', '@'})
    worksheet.write_string('A1', '01209', str_format)

This behaviour, while slightly tedious, is unfortunately consistent with the
way Excel handles string data that looks like numbers. See :ref:`tutorial3`.


worksheet.write_number()
------------------------

.. py:function:: write_number(row, col, number[, cell_format])

   Write a number to a worksheet cell.

   :param row:         The cell row (zero indexed).
   :param col:         The cell column (zero indexed).
   :param number:      Number to write to cell.
   :param cell_format: Optional Format object.
   :type  row:         integer
   :type  col:         integer
   :type  number:      int or float
   :type  cell_format: :ref:`Format <format>`

The ``write_number()`` method writes an integer or a float to the cell
specified by ``row`` and ``column``::

    worksheet.write_number(0, 0, 123456)
    worksheet.write_number('A2', 2.3451)

Both row-column and A1 style notation are support. See :ref:`cell_notation` for
more details.

The ``cell_format`` parameter is used to apply formatting to the cell. This
parameter is optional but when present is should be a valid
:ref:`Format <format>` object.

Excel handles numbers as IEEE-754 64-bit double-precision floating point. This
means that, in most cases, the maximum number of digits that can be stored in
Excel without losing precision is 15.


worksheet.write_formula()
-------------------------

.. py:function:: write_formula(row, col, formula[, cell_format[, value]])

   Write a formula to a worksheet cell.

   :param row:         The cell row (zero indexed).
   :param col:         The cell column (zero indexed).
   :param formula:     Formula to write to cell.
   :param cell_format: Optional Format object.
   :type  row:         integer
   :type  col:         integer
   :type  formula:     string
   :type  cell_format: :ref:`Format <format>`

The ``write_formula()`` method writes a formula or function to the cell
specified by ``row`` and ``column``::

    worksheet.write_formula(0, 0, '=B3 + B4')
    worksheet.write_formula(1, 0, '=SIN(PI()/4)')
    worksheet.write_formula(2, 0, '=SUM(B1:B5)')
    worksheet.write_formula('A4', '=IF(A3>1,"Yes", "No")')
    worksheet.write_formula('A5', '=AVERAGE(1, 2, 3, 4)')
    worksheet.write_formula('A6', '=DATEVALUE("1-Jan-2013")')

Array formulas are also supported::

    worksheet.write_formula('A7', '{=SUM(A1:B1*A2:B2)}')

See also the ``write_array_formula()`` method below.

Both row-column and A1 style notation are support. See :ref:`cell_notation` for
more details.

The ``cell_format`` parameter is used to apply formatting to the cell. This
parameter is optional but when present is should be a valid
:ref:`Format <format>` object.

XlsxWriter doesn't calculate the value of a formula and instead stores the
value 0 as the formula result. It then sets a global flag in the XLSX file to
say that all formulas and functions should be recalculated when the file is
opened. This is the method recommended in the Excel documentation and in
general it works fine with spreadsheet applications. However, applications
that don't have a facility to calculate formulas, such as Excel Viewer, or
some mobile applications will only display the 0 results.

If required, it is also possible to specify the calculated result of the
formula using the options ``value`` parameter. This is occasionally necessary
when working with non-Excel applications that don't calculate the value of the
formula. The calculated ``value`` is added at the end of the argument list::

    worksheet.write('A1', '=2+2', num_format, 4)

.. note::
   Some early versions of Excel 2007 do not display the calculated values of
   formulas written by XlsxWriter. Applying all available Office Service
   Packs should fix this.


worksheet.write_array_formula()
-------------------------------

.. py:function:: write_array_formula(first_row, first_col, last_row, \
                                    last_col, formula[, cell_format[, value]])

   Write an array formula to a worksheet cell.

   :param first_row:   The first row of the range. (All zero indexed.)
   :param first_col:   The first column of the range.
   :param last_row:    The last row of the range.
   :param last_col:    The last col of the range.
   :param formula:     Array formula to write to cell.
   :param cell_format: Optional Format object.
   :type  first_row:   integer
   :type  first_col:   integer
   :type  last_row:    integer
   :type  last_col:    integer
   :type  formula:     string
   :type  cell_format: :ref:`Format <format>`

The ``write_array_formula()`` method write an array formula to a cell range. In
Excel an array formula is a formula that performs a calculation on a set of
values. It can return a single value or a range of values.

An array formula is indicated by a pair of braces around the formula:
``{=SUM(A1:B1*A2:B2)}``. If the array formula returns a single value then the ``first_`` and ``last_`` parameters should be the same::

    worksheet.write_array_formula('A1:A1', '{=SUM(B1:C1*B2:C2)}')

It this case however it is easier to just use the ``write_formula()`` or
``write()`` methods::

    # Same as above but more concise.
    worksheet.write('A1', '{=SUM(B1:C1*B2:C2)}')
    worksheet.write_formula('A1', '{=SUM(B1:C1*B2:C2)}')

For array formulas that return a range of values you must specify the range
that the return values will be written to::

    worksheet.write_array_formula('A1:A3',    '{=TREND(C1:C3,B1:B3)}')
    worksheet.write_array_formula(0, 0, 2, 0, '{=TREND(C1:C3,B1:B3)}')

As shown above, both row-column and A1 style notation are support. See
:ref:`cell_notation` for more details.

The ``cell_format`` parameter is used to apply formatting to the cell. This
parameter is optional but when present is should be a valid
:ref:`Format <format>` object.

If required, it is also possible to specify the calculated value of the
formula. This is occasionally necessary when working with non-Excel
applications that don't calculate the value of the formula. The calculated
``value`` is added at the end of the argument list::

    worksheet.write_array_formula('A1:A3', '{=TREND(C1:C3,B1:B3)}', format, 105)

In addition, some early versions of Excel 2007 don't calculate the values of
array formulas when they aren't supplied. Installing the latest Office Service
Pack should fix this issue.



worksheet.write_blank()
-----------------------

.. py:function:: write_blank(row, col, blank[, cell_format])

   Write a blank worksheet cell.

   :param row:         The cell row (zero indexed).
   :param col:         The cell column (zero indexed).
   :param blank:       None or empty string. The value is ignored.
   :param cell_format: Optional Format object.
   :type  row:         integer
   :type  col:         integer
   :type  cell_format: :ref:`Format <format>`

Write a blank cell specified by ``row`` and ``column``::

    worksheet.write_blank(0, 0, None, format)

This method is used to add formatting to a cell which doesn't contain a string
or number value.

Excel differentiates between an "Empty" cell and a "Blank" cell. An "Empty"
cell is a cell which doesn't contain data whilst a "Blank" cell is a cell
which doesn't contain data but does contain formatting. Excel stores "Blank"
cells but ignores "Empty" cells.

As such, if you write an empty cell without formatting it is ignored::

    worksheet.write('A1', None, format)  # write_blank()
    worksheet.write('A2', None)          # Ignored

This seemingly uninteresting fact means that you can write arrays of data
without special treatment for ``None`` or empty string values.

As shown above, both row-column and A1 style notation are support. See
:ref:`cell_notation` for more details.


worksheet.write_datetime()
--------------------------

.. py:function:: write_datetime(row, col, datetime [, cell_format])

   Write a date or time to a worksheet cell.

   :param row:         The cell row (zero indexed).
   :param col:         The cell column (zero indexed).
   :param datetime:    A datetime.datetime object.
   :param cell_format: Optional Format object.
   :type  row:         integer
   :type  col:         integer
   :type  formula:     string
   :type  datetime:    :class:`datetime.datetime`
   :type  cell_format: :ref:`Format <format>`

The ``write_datetime()`` method can be used to write a date or time to the cell
specified by ``row`` and ``column``::

    worksheet.write_datetime(0, 0, datetime, date_format)

The :class:`datetime.datetime` class is part of the standard Python
:mod:`datetime` library.

There are many way to create a datetime object but the most common is to use
the :meth:`datetime.strptime <datetime.datetime.strptime>` method::

    date_time = datetime.strptime('2013-01-23', '%Y-%m-%d')

A date should always have a ``cell_format`` of type :ref:`Format <format>`,
otherwise it will appear as a number::

    date_format = workbook.add_format({'num_format': 'd mmmm yyyy'})

    worksheet.write_datetime('A1', date_time, date_format)

See :ref:`working_with_dates_and_time` for more details.


worksheet.set_row()
-------------------

.. py:function:: set_row(row, height, cell_format, options)

   Set properties for a row of cells.
   
   :param int row:      The worksheet row (zero indexed).
   :param int height:   The row height.
   :param cell_format:  Optional Format object.
   :type  cell_format:  :ref:`Format <format>`
   :param dict options: Optional row parameters: hidden, level, collapsed.

The ``set_row()`` method is used to change the default properties of a row. The
most common use for this method is to change the height of a row::

    worksheet.set_row(0, 20)  # Set the height of Row 1 to 20.

The other common use for ``set_row()`` is to set the :ref:`Format <format>` for
all cells in the row::

    cell_format = workbook.add_format({'bold': True})

    worksheet.set_row(0, 20, cell_format)

If you wish to set the format of a row without changing the height you can pass
``None`` as the height parameter or use the default row height of 15::

    worksheet.set_row(1, None, cell_format)
    worksheet.set_row(1, 15,   cell_format)  # Same as this.

The ``cell_format`` parameter will be applied to any cells in the row that
don't have a format. As with Excel it is overidden by an explicit cell format.
For example::

    worksheet.set_row(0, None, format1)      # Row 1 has format1.
    
    worksheet.write('A1', 'Hello')           # Cell A1 defaults to format1.
    worksheet.write('B1', 'Hello', format2)  # Cell B1 keeps format2.

The ``options`` parameter is a dictionary with the following possible keys:

* ``'hidden'``
* ``'level'``
* ``'collapsed'``

Options can be set as follows::

    worksheet.set_row(0, 20, cell_format, {'hidden': 1})
    
    # Or use defaults for other properties and set the options only.
    worksheet.set_row(0, None, None, {'hidden': 1})
    
The ``'hidden'`` option is used to hide a row. This can be used, for example,
to hide intermediary steps in a complicated calculation::

    worksheet.set_row(0, 20, cell_format, {'hidden': 1})

The ``'level'`` parameter is used to set the outline level of the row. Outlines
are described in "Working with Outlines and Grouping". Adjacent rows with the
same outline level are grouped together into a single outline. (**Note**: This
feature is not implemented yet).

The following example sets an outline level of 1 for some rows::

    worksheet.set_row(0, None, None, {'level': 1})
    worksheet.set_row(1, None, None, {'level': 1})
    worksheet.set_row(2, None, None, {'level': 1})

.. note::
   Excel allows up to 7 outline levels. The ``'level'`` parameter
   should be in the range ``0 <= level <= 7``.

The ``'hidden'`` parameter can also be used to hide collapsed outlined rows
when used in conjunction with the ``'level'`` parameter::

    worksheet.set_row(1, None, None, {'hidden': 1, 'level': 1})
    worksheet.set_row(2, None, None, {'hidden': 1, 'level': 1})

The ``'collapsed'`` parameter is used in collapsed outlines to indicate which
row has the collapsed ``'+'`` symbol::

    worksheet.set_row(3, None, None, {'collapsed': 1})


worksheet.set_column()
----------------------

.. py:function:: set_column( first_col, last_col, width, cell_format, \
                             hidden, level, collapsed )
   Set properties for one or more columns of cells.
   
   :param int first_col: First column (zero-indexed).
   :param int last_col:  Last column (zero-indexed). Can be same as firstcol.
   :param int width:     The width of the column(s).
   :param cell_format:   Optional Format object.
   :type  cell_format:   :ref:`Format <format>`
   :param dict options:  Optional parameters: hidden, level, collapsed.
   
The ``set_column()``  method can be used to change the default properties of a
single column or a range of columns::

    worksheet.set_column(1, 3, 30)  # Width of columns B:D set to 30.

If ``set_column()`` is applied to a single column the value of ``first_col``
and ``last_col`` should be the same::

    worksheet.set_column(1, 1, 30)  # Width of column B set to 30.

It is also possible, and generally clearer, to specify a column range using the
form of A1 notation used for columns. See :ref:`cell_notation` for more
details.

Examples::

    worksheet.set_column(0, 0, 20)   # Column  A   width set to 20.
    worksheet.set_column(1, 3, 30)   # Columns B-D width set to 30.
    worksheet.set_column('E:E', 20)  # Column  E   width set to 20.
    worksheet.set_column('F:H', 30)  # Columns F-H width set to 30.

The width corresponds to the column width value that is specified in Excel. It
is approximately equal to the length of a string in the default font of
Calibri 11. Unfortunately, there is no way to specify "AutoFit" for a column
in the Excel file format. This feature is only available at runtime from
within Excel. It is possible to simulate "AutoFit" by tracking the width of
the data in the column as your write it.

As usual the ``cell_format`` :ref:`Format <format>`  parameter is optional. If
you wish to set the format without changing the width you can pass ``None`` as
the width parameter::

    cell_format = workbook.add_format({'bold': True})

    worksheet.set_column(0, 0, None, cell_format)

The ``cell_format`` parameter will be applied to any cells in the column that
don't have a format. For example::

    worksheet.set_column('A:A', None, format1)  # Col 1 has format1.
    
    worksheet.write('A1', 'Hello')              # Cell A1 defaults to format1.
    worksheet.write('A2', 'Hello', format2)     # Cell A2 keeps format2.

A  row format takes precedence over a default column format::

    worksheet.set_row(0, None, format1)         # Set format for row 1.
    worksheet.set_column('A:A', None, format2)  # Set format for col 1.
    
    worksheet.write('A1', 'Hello')              # Defaults to format1
    worksheet.write('A2', 'Hello')              # Defaults to format2

The ``options`` parameter is a dictionary with the following possible keys:

* ``'hidden'``
* ``'level'``
* ``'collapsed'``

Options can be set as follows::

    worksheet.set_column('D:D', 20, cell_format, {'hidden': 1})

    # Or use defaults for other properties and set the options only.
    worksheet.set_column('E:E', None, None, {'hidden': 1})

The ``'hidden'`` option is used to hide a column. This can be used, for
example, to hide intermediary steps in a complicated calculation::

    worksheet.set_column('D:D', 20,  cell_format, {'hidden': 1})

The ``'level'`` parameter is used to set the outline level of the column.
Outlines are described in "Working with Outlines and Grouping". Adjacent
columns with the same outline level are grouped together into a single
outline. (**Note**: This feature is not implemented yet).

The following example sets an outline level of 1 for columns B to G::

    worksheet.set_column('B:G', None, None, {'level': 1})

.. note::
   Excel allows up to 7 outline levels. The ``'level'`` parameter
   should be in the range ``0 <= level <= 7``.

The ``'hidden'`` parameter can also be used to hide collapsed outlined columns
when used in conjunction with the ``'level'`` parameter::

    worksheet.set_column('B:G', None, None, {'hidden': 1, 'level': 1})

The ``'collapsed'`` parameter is used in collapsed outlines to indicate which
column has the collapsed ``'+'`` symbol::

    worksheet.set_column('H:H', None, None, {'collapsed': 1})


worksheet.activate()
--------------------

.. py:function:: activate()

   Make a worksheet the active, i.e., visible worksheet.

The ``activate()`` method is used to specify which worksheet is initially
visible in a multi-sheet workbook::

    worksheet1 = workbook.add_worksheet()
    worksheet2 = workbook.add_worksheet()
    worksheet3 = workbook.add_worksheet()

    worksheet3.activate()

.. image:: _static/worksheet_activate.png

More than one worksheet can be selected via the ``select()`` method, see below,
however only one worksheet can be active.

The default active worksheet is the first worksheet.


worksheet.select()
------------------

.. py:function:: select()

   Set a worksheet tab as selected.

The ``select()`` method is used to indicate that a worksheet is selected in a
multi-sheet workbook::

    worksheet1.activate()
    worksheet2.select()
    worksheet3.select()

A selected worksheet has its tab highlighted. Selecting worksheets is a way of
grouping them together so that, for example, several worksheets could be
printed in one go. A worksheet that has been activated via the ``activate()``
method will also appear as selected.
