Fits Table

### Table display

The table window presents a spreadsheet-like display of the contents of the given FITS table extension. Row numbers run along the left side of the window and column names run along the top (below the menubar). Single click on a data cell to copy the value to the "Edit cell" entry at the bottom of the window, where one can immediately edit the value. Press <Return> in that entry to finalize the changes.

Below the column names are listed the data formats and (if present) the units labels for the columns. If an "Expand" button appears below the column information, the column is a vector column. Clicking on the "Expand" button will bring up a 2-D table, displaying all the vector elements.

#### Menus

Not all of the following menu items are supported in all table windows. Many apply only to tables of real table extensions, but not to vector tables.

- File
  - Save: Save current FITS file. If the current extension has not been modified, this menu item is disabled.
  - Export HDU: The whole or partial table will be saved as a new fits file.
  - Export as Text: You will be able to specify which rows and columns to list, as well as any special separater character(s) to be inserted in between the values on each row. You may optionally choose which rows to be listed by highlighting the desired row numbers in the first column of the table or by using "Select Rows from Expr" under the Edit munu.
  - Close: Close the table window.
- Edit
  - Undo: Not supported in table windows.
  - Cut: Not supported in table windows.
  - Copy: To highlight a rectangular region of a table, first left-click on the table cell in one corner of the rectangle, then right-click on the cell in the opposite corner (Shift-Click on MacOS).
  - Paste: Paste the contents of the clipboard at the location of the current selection/region.
  - Clear: Not supported in table windows.
  - Clipboard: Bring up contents of the clipboards. If the type is listed as "table", its contents can be pasted into the table. Data types could conflict and give incorrect results or errors.
  - Insert ->
    - Row: A new row information window will appear in which the number of rows and their insertion point are entered. Enter "end" as the insertion point to append rows to the table.
    - Column: You will be presented with a new column information window in which you can specify the column's name, its data format, its optional units label and display format, and where to place the new column. The name and format are required. Sample legal format for a binary table are 15A (string of 15 characters), 1L, 1X, 1B, 1I, 1J, 1E, 1D, 1C, 1M. A bintable column of type Xn is a vector of n elements). For ASCII tables, sample format types are A15, I10, E12.5, D20.10, F14.6, etc. Allowed formats for each table type are selectable in a popup menu.
  - Delete ->
    - Selected Rows: Delete all the selected row(s). Rows can be selected (unselected) by clicking mouse on the rows or by clicking Selected Rows From Expr button in Edit menu.
    - Selected Columns: Delete all the selected column(s). To select (or unselect) a column, click on the checkbox next to the column's name in the main window.
  - Select Rows From Expr...: Select rows from the table, provide either a list of row range or a conditional expression (see Selected Rows From Expr).

  - Column Parameters...: Change the display format of a column by adding/modifying the column's TDISP keyword. Select the column from the popup menu then type in a new TDISP value and click the "Apply" button. Leave the entry box blank to delete the TDISP keyword. Legal TDISP keywords have the format of: Aw Lw Iw.m Bw.m Ow.m Zw.m Fw.d Ew.dEe ENw.d ESw.d Gw.dEe Dw.dEe (see Column Parameter help file and FITS documentation for details). Example formats:
    - I6 : display as integers of width 6
    - F5.2: display as floating points of width 5 with 2 digits after decimal point.
  - Preferences: Bring up the Preferences window.

- Tools
  - Plot

    Create a scatter plot of table data. A column selection window will appear, from which you can select the columns to plot. You can also enter arithmetic expressions. See Plot Dialog for details.

  - Sort Rows

    Sort the table. You can select from the dialog box, at most, three columns to sort on. The sorted table will replace the original table, so the FITS file must be opened as read/write. A "delete duplicates" option can be given to eliminate extra rows with identical sort keys. (See Sort Columns for more details.)

  - Calculator

    Perform a calculation with the table. You will be presented with a calculator-like dialog box in which you can enter an arithmetic expression to evaluate for each row of the table. You can store the results in either a new column or a pre-existing one. See the Calculator help file for more details.

  - Histogram

    Make a 1D or 2D histograms from column(s). The histogram dialog box gives you control over the histogram size, binning, and row range to use. See Histogram help file for details.

  - Statistics

    Calculate statistical information (mean, std. dev, etc) on a table's columns. See Column Statistics for details.

- Help

  List of all the available help files.

#### User entries

Two entry boxes are located at the bottom of the Table window:

- Go to: Scroll the window to display the row specified in the entry field. Either click the "Go To" button or hit <Return> to move to the indicated row.
- Edit cell: Highlighting a cell in the table will copy the value to this entry, in which the value can be edited. To set a table element as undefined, one can enter "NULL" as the value (TNULLn keyword must be present in the header). Press <Return> to copy the new value into the table.

#### Column Entries

Select

Selection will be highlighted in yellow.

- All: Select all rows.
- Invert: Counter-select of selected (if any) row(s). If no selection has been made, previously, all rows will be selected when this button is pressed.

Modify

- Expand: Expanding the column. This button only exists if the column is a 2-D array.
- Sort: Sorting the column (thus the whole table) via two pull-down menu tabs (Ascending and Decdending),
- Move Before: Moving the selected column to before one of the other columns, or end of the table.
- Show Col: Show hidden column(s). It will be greyed out if there is no hidden column.
- Hide Column: Hide current column.
- Insert New Column: Open the insertion dialog panel for creating a new column on the right to current column.
- Delete: Delete current column.
- Parameter: Open column parameter editting panel.

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