6.7.3 Edit Rows or Columns

1

Insert blank rows into an existing ASCII or binary table (in the CDU). All the rows FOLLOWING row FROW are shifted down by NROWS rows. If FROW or FROWLL equals 0 then the blank rows are inserted at the beginning of the table. These routines modify the NAXIS2 keyword to reflect the new number of rows in the table. Note that it is *not* necessary to insert rows in a table before writing data to those rows (indeed, it would be inefficient to do so). Instead, one may simply write data to any row of the table, whether that row of data already exists or not.

        FTIROW(unit,frow,nrows, > status)
        FTIROWLL(unit,frowll,nrowsll, > status)

2

Delete rows from an existing ASCII or binary table (in the CDU). The NROWS (or NROWSLL) is the number of rows are deleted, starting with row FROW (or FROWLL), and any remaining rows in the table are shifted up to fill in the space. These routines modify the NAXIS2 keyword to reflect the new number of rows in the table.

        FTDROW(unit,frow,nrows, > status)
        FTDROWLL(unit,frowll,nrowsll, > status)

3

Delete a list of rows from an ASCII or binary table (in the CDU). In the first routine, 'rowrange' is a character string listing the rows or row ranges to delete (e.g., '2-4, 5, 8-9'). In the second routine, 'rowlist' is an integer array of row numbers to be deleted from the table. nrows is the number of row numbers in the list. The first row in the table is 1 not 0. The list of row numbers must be sorted in ascending order.

        FTDRRG(unit,rowrange, > status)
        FTDRWS(unit,rowlist,nrows, > status)

4

Insert a blank column (or columns) into an existing ASCII or binary table (in the CDU). COLNUM specifies the column number that the (first) new column should occupy in the table. NCOLS specifies how many columns are to be inserted. Any existing columns from this position and higher are moved over to allow room for the new column(s). The index number on all the following keywords will be incremented if necessary to reflect the new position of the column(s) in the table: TBCOLn, TFORMn, TTYPEn, TUNITn, TNULLn, TSCALn, TZEROn, TDISPn, TDIMn, TLMINn, TLMAXn, TDMINn, TDMAXn, TCTYPn, TCRPXn, TCRVLn, TCDLTn, TCROTn, and TCUNIn.

        FTICOL(unit,colnum,ttype,tform, > status)
        FTICLS(unit,colnum,ncols,ttype,tform, > status)

5

Modify the vector length of a binary table column (e.g., change a column from TFORMn = '1E' to '20E'). The vector length may be increased or decreased from the current value.

        FTMVEC(unit,colnum,newveclen, > status)

6

Delete a column from an existing ASCII or binary table (in the CDU). The index number of all the keywords listed above (for FTICOL) will be decremented if necessary to reflect the new position of the column(s) in the table. Those index keywords that refer to the deleted column will also be deleted. Note that the physical size of the FITS file will not be reduced by this operation, and the empty FITS blocks if any at the end of the file will be padded with zeros.

        FTDCOL(unit,colnum, > status)

7

Copy a column from one HDU to another (or to the same HDU). If createcol = TRUE, then a new column will be inserted in the output table, at position `outcolumn', otherwise the existing output column will be overwritten (in which case it must have a compatible datatype). Note that the first column in a table is at colnum = 1.

        FTCPCL(inunit,outunit,incolnum,outcolnum,createcol, > status);