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  SOFA Library Issue 2021-05-12 for Fortran 77

This is the master page for the SOFA Library Issue 2021-05-12 for Fortran 77. From here you can find your way to all the resources comprising this Issue, including notes and source download pages.


Issue 2021-05-12 is the eighteenth release of the SOFA Library for Fortran 77.


The complete SOFA Library source set is available in a single download bundle for Unix (including macOS) or Windows systems. This is the preferred method of obtaining the SOFA Library. The Fortran SOFA Library Issue 2021-05-12 is available to download in various formats.

Please note: Tarballs contain files with Unix line-terminations and Zip archives contain files with DOS line-terminations. Please download the appropriate file for your operating system.

Structure created by unpacking the Fortran 77 release tar / zip files:

---- sofa
       ---- 20210512 (issue date) ---- ... any other (sub-)releases ---- ...
                |                                   |
                ---- f77 (00READ.ME)                ---- f77 (00READ.ME)  
                      |                                   |
                      ---- doc (*.lis, *.pdf)             ---- doc (*.lis, *.pdf)
                      |                                   |
                      ---- src (*.for, makefile)          ---- src (*.for, makefile)

  Additional Information - Compiler Issue

Testing indicates that some Fortran compilers on some platforms may not comply fully with the parenthesis integrity stipulations of the ANSI standard. This problem may manifest itself when running the Fortran test program t_sofa_f.for by reporting the failure of a particular routine, usually with a discrepancy of the order of 10-13, which results in a "Validation failed" message. Rather than relaxing the standards of the testing process, we are bringing this finding to the attention of users of the SOFA Fortran Library. If you do experience this issue, please i) recompile both the test software and the library of routines without optimization (e.g. using options of the form -O0 rather than relying on the default state of optimization of the compiler) and try again and ii) contact the SOFA Board providing information on your compiler, operating system, hardware and which optimization options were set, if any, including those used by default.

This problem does not affect the ANSI C library.


The SOFA product documentation is available in Adobe Portable Document Format (pdf) or plain ASCII text files to guarantee platform independence.The manual may be downloaded as a single file or in sections if you prefer.

PLEASE NOTE: Any updates, improvements or corrections to the documentation for this release will be posted here.

  • Complete manual [pdf (462102 bytes), ASCII].
Sections (in order):
  • Title page [pdf (6087 bytes), ASCII].
  • Introduction [pdf (15039 bytes), ASCII].
  • Vector/Matrix library [pdf (15284 bytes), ASCII].
  • Astronomy Library [pdf (23708 bytes), ASCII].
  • Routine descriptions (Complete manual only).
  • Copyright notice [pdf (11612 bytes), ASCII].
  • Constants [pdf (8483 bytes), ASCII].
  • Review Board [pdf (8610 bytes), ASCII].
  • Changes [pdf (11442 bytes), ASCII] since the previous release.



The source for the SOFA Library may be viewed from the complete list index. In addition the routines are indexed by section and subsection:
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Last modified: 2021 May 11
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