| A requirement of many experiments is
the ability to generate tabular output for further analysis in a spreadsheet
or statistics program. The table editor is the means by which you
can generate a series of statistical calculations for all samples
in a group. These statistics can be any of the statistics FlowJo calculates:
medians, frequencies, etc. In order to generate a table, you will
first have to generate the statistics you wish to export on at least
one sample.
From the workspace window, open the table editor. This can be done
in one of two ways: either click on the table editor function button
in the workspace window (the fourth button in the top left corner),
or select the table window from the Windows
menu (command-T). This will bring up the table view window, from
which you can easily create previously-defined table outputs.

Use the Table Editor to define a new table definition.
A table definition is not the output data itself. Instead
it is the specification of what columns the table will contain,
when it is generated. You can have as many table definitions
in the workspace as you wish. You can create new empty definitions,
duplicate
existing ones, or delete them using the button in the top left corner
of the window.
To add statistics to a table definition, simply
click on them in the workspace window and drag them to the definition
pane on the right hand side of the table editor window. (You can
use the control and option keys to modify whether or not you want
to take all the parents or children, respectively; for more information,
see the pages about dragging and dropping
nodes.) When you drag a population node into the table editor,
it assumes that you want the frequency of parent (or frequency of
total depending on which statistic is set as your default in the
preferences) for that gate as the statistic.
Each statistic in the right panel of the table editor
will correspond to a column in the output table; you can change
the order of these columns by clicking and dragging the statistics
around. The table is created for those samples in the currently-selected
group: remember to click on the appropriate group in the workspace
window before you create the table!
Only drag statistics from a single sample into
the table editor (the table editor will automatically
calculate these statistics for each sample in the group). When you
apply or create a table, each row in the table editor is applied
to every sample in the current group--irrespective of which node
you actually dragged into the table. Each different table definition
in the table editor is a different template.
When you create a table, FlowJo will cycle through
all of the samples in the currently-selected group. For each statistic
node that you have dragged into the table definition, it searches
for the same node in each sample. If the node does not exist, then
it leaves a blank for that entry. (For instance, if the statistic
you copied was the median FITC fluorescence of a "Lymphocyte"
gate, and the "Lymphocyte" gate does not exist in all
samples, then those samples will have blank values for this statistic).
Therefore, the statistics are only gathered for those samples which
have the appropriate gates and statistics already applied to them.
Keywords.
The table editor also supports including sample file keywords.
A keyword is any attribute listed in the text section of the FCS
file. Above the list of columns is a button with a picture
of a key on it. Press this button to bring up a dialog which
will allow you to select the keyword(s) to be included in the table.
You can use shift- and command- clicking to selection multiple items
from the list. Keywords are appended to the table definition. There
is a list of standard keywords, as defined
by the FCS specification. Note that not all files will contain all
keywords.
Generating the Table. Once you have put all
the desired statistics and keywords into the table definition, click
on the Table button in the top left corner of the definition window.
This will invoke the table generation process. FlowJo will cycle
through all of the samples in the current group, and calculate all
possible statistics and keywords that are in the table definition.
It will then create a new window containing a spreadsheet-like view
of the statistics. This table can be saved to the clipboard or a
file, printed or exported to another application. Each of these
operations is initiated via the buttons in the top left corner of
the table window. The application launched by the "save and
launch application" button (fourth from left) is chosen the
first time you use this function and can be altered in the Layout
pane of the Preferences window.

Sorting the Table. Many times it is useful
to view the table ordered by the value of a keyword or statistic.
To sort the table, double click on the header of the column by which
you wish to sort. By default, sorting the table will order the rows
in descending order of the values in that column. If you wish to
reverse the order, and view the table with the smallest value first,
then double click the column again to invert the row order.
Copying Part of a Table. Normally if you
copy a table, the entire table will be copied to the clipboard,
regardless of the current selection. If you wish to copy just a
portion of the table, you can select any number of cells, and hold
down the option key while performing the copy (either via the button
in that window or the Copy command in the Edit menu). If the option
key is down, then only the selected cell contents will be put on
the clipboard. If the selection is rectangular, then pasting the
clipboard into a spreadsheet or word processor will result in output
that looks the same as in did in FlowJo's table. If you have used
the command key to select an odd shape or disjoint selection, then
the resulting paste may not look the same as it did in FlowJo's
table. The rule is that all cells that are in the same row in FlowJo's
table will come out in the same row on the clipboard (i.e., will
be separated by tab characters), and cells that are on separate
rows will end up on separate rows (i.e., will be separated by carriage
return characters), but gaps between either rows or columns will
be omitted.
Creating
Groups from the Table Selection. Sometimes it is useful to be
able to use the results from the tables to refine analysis in the
workspace. To facilitate this, the table window has a button similar
to the one in the workspace for Create Group operation. Clicking
this button will create a group containing all of the samples which
have one or more selected cells in the table. You don't need to
select the sample name. Any cell in that row will be sufficient
to include that sample in the new group.
For example, we might be interested in producing
graphical output of all of the samples whose CD45 positive population
is over 60% of total events. To accomplish this, you could generate
a table containing the statistic for CD45+, sort the table by this
column, click the first cell, shift click the last cell that has
a frequency over 60%, and then click on the New Group button in
order to create a group of all samples with a selected cell. Then
go back to the workspace window, and select the new group, limiting
the view to only the desired samples. Now when you generated the
desired layout, you will only be looking at those samples that have
the desired characteristics. (If this sounds overly complex, relax.
It's easier to do than to explain.)
Finally,
you can choose the resulting table to be saved to a disk file, copied
to the clipboard. Saving to a disk file is probably the best choice;
you can then import the data into a spreadsheet. Any spreadsheet
should be able to import the data; specify that the first row of
the table has the column headers.
Column Names. In the output file, the
first line has a tab-delimited list of column names. Each
column name is a concatenation of the full name of the population
(including all "parents") and the statistic name itself.
For example, "Lymphocytes/CD4:Freq. of Parent" would be
the name for the column with the frequencies of CD4 cells within
the Lymphocyte gate. These names can become unwieldy in length...
you might want to keep your subset names as short as possible.
In addition, you can have FlowJo export abbreviated statistic names
(in the example above, "Freq. of Parent" would be replaced
by "%P"). You can set this preference in the Preferences
for Tables & Layouts.
Replace Column Names. You can type in any
name you wish to replace the statistic names in the generated table.
In the Table Editor, type in the new names in the "Column Name"
column. When you create a table, these names will be displayed instead
of FlowJo's statistic name.
|