I/O Options and Subcase Information Entry The ECHO command can be used in the I/O Options section causing the output of the interpreted forms of Subcase Information and Bulk Data Entries to the .out file. The ECHOON command can be used in the I/O Options, Subcase Information, or Bulk Data sections causing the (verbatim) output of any subsequent I/O Options, Subcase Information, or Bulk Data Entries to the .out file until an ECHOOFF command is encountered. The ECHOOFF command can be used in the I/O Options, Subcase Information, or Bulk Data sections suppressing the output of any subsequent I/O Options, Subcase Information, or Bulk Data Entries to the .out file until and ECHOON command is encountered.


ECHO = option1

ECHOON = option2





Argument Options Description
option1 <SHORT, PUNCH, OPUNCH, {cardname}, EXCEPT {cardname}, blank>


Only entries having 20 or less instances are echoed to the .out file.
Writes interpreted echo of all Bulk Data Entries to the .echo file.
Writes interpreted echo of specific Bulk Data Entries to the .echo file only.
Only Bulk Data Entries with the given {cardname} are echoed to the .out file.
EXCEPT {cardname}
Only Bulk Data Entries with the given {cardname} are not echoed.
blank (Default)
Writes interpreted forms of all Subcase Information and Bulk Data Entries to the .out file.
Adds all cards of the specified class to the list for ECHO.
Option2 <PARSED>
Bulk Data Entries are converted to free format (comma separated) before echoing.
blank (Default)
Bulk Data Entries are echoed verbatim.


  1. When an ECHO command is not present, no input information is echoed.
  2. The interpreted echo always includes SUBCASE cards (solution related), but not output control cards.
  3. The cards are organized within groups, for example, optimization cards appear after model definition cards, and most cards are sorted by their numerical IDs.
  4. The interpreted echo may contain some cards that are automatically generated or converted during reading (for example, a CQUADR card shows as CQUAD4, or a CMASS1 card shows as a CMASS3 when only scalar points are referenced). Unreferenced cards may not show in the printout. PARAM,DOPTRM,OSDIAG will not be shown.
  5. ECHO will be produced from internal representation of each card; thus, it will be equivalent, but not identical to the input:
    • For most of the optional fields, the blank from input will be printed in ECHO as default value.
    • Fields which are not recognized or not used by OptiStruct are left blank.
    • Some values which would generate warning on the input will be printed after adjustment.
    • Optional continuation cards may be printed even if they did not appear in the input.
  6. The interpreted echo is always printed using a fixed field format (8 character fields) except GRID and DMIG cards, which are printed using free format (comma separated fields) with 10 decimal digits accuracy.
    Note: The use of IDs larger than 99,999,999 is allowed, but ECHO will not be usable in these cases as such IDs cannot be printed in fixed format.
    DMIG cards are usually very large and are not shown in the interpreted echo. Adding the card:

    anywhere in the control section will force full printout of DMIG cards if the interpreted echo is requested.

  7. {cardname} contains the list of all cards which are to be included in the interpreted echo (or excluded, if EXCEPT keyword is present). This list may contain ELEM, MAT, or PROP keywords, which is equivalent to listing all valid element, material, or property names, respectively.
  8. Multiple ECHO cards are allowed; all parameters of these cards are accumulated in the order in which they are input. EXCEPT may appear anywhere (for example, before or after {cardname} list) and may be repeated on multiple cards.
  9. ECHOON/ECHOOFF cards may appear in any section of the input deck.
  10. All comment cards, empty cards, and characters after the $ character on any card will not be printed in any ECHO format.
  11. The .echo file generated when ECHO = PUNCH is defined represents a copy of the input deck in a form suitable to use for another solution which, when used with the same Subcase Information and I/O Options Entries, should generate identical results when missing entries (PARAM, DOPTPRM, OSDIAG) are added as required (round off error may be noticeable if the original input deck uses large field format). However, in some cases, the ECHO may require manual editing before being acceptable as input for OptiStruct. In particular, some optimization cards may be printed with information already modified internally, and not correct. Also some cards with a negative ID may be printed in ECHO; those cards are automatically generated internally to OptiStruct, and should simply be deleted.