Fortran Compilers for Use with Source-Code GEMPACK

A suitable Fortran compiler is required for use with all Source-code versions of GEMPACK. We cannot supply these compilers; they must be purchased separately.

For GEMPACK Releases 8 through 10 running on Windows PCs, 2 Lahey compilers are supported. For GEMPACK Release 10, the Intel Fortran compiler will also be supported.

Lahey Fortrans

Lahey currently sells two Fortran compilers for Windows PCs.

• The current one is called Lahey/Fujitsu Fortran (LF). We recommend the cheapest version, called LF Express -- around $US250. [Until recently this Lahey/Fujitsu compiler was called LF95. It is referred to as LF95 in the GEMPACK documentation and when you install GEMPACK.]
  An LF Express single-user licence requires internet activation and can be installed on one PC only.
• The older version is called LF90. You can use this with Releases 8.0 through 10.0 of GEMPACK, but we will not support it for GEMPACK Release 11. If you need to buy Fortran, we do not recommend that you buy this one.

See more details at http://www.lahey.com

Intel Fortran

GEMPACK Release 10.0-001 supports Versions 10.1 and 11.0 of the Intel Fortran compiler. This also is excellent. Again we recommend the cheapest version, called Intel Visual Fortran Compiler 11.0 Professional Edition for Windows. Purchasers actually receive two versions of the compiler: one for producing 32-bit EXEs, and one for producing 64-bit EXEs. So if you are in the small group who wishes to run a really huge model (on 64-bit Windows), choose the Intel compiler.

An Intel Fortran single-user licence does not require internet activation and can be installed on several PCs used by one person.

See more details at http://www.intel.com (choose Products.....Software.....Compilers to locate the Fortran pages).

We urge you to read our notes on installing Intel Fortran for GEMPACK use, here. In particular note the advice to use Intel Fortran 10.1.021 (Build 20080312) or later.

Update April 2009: GEMPACK now supports Intel Fortran version 11, although early versions were buggy. We suggest you upgrade (it is free) to version 11.1 or later.

Purchasing your compiler

You can purchase the Intel compiler direct from Intel on the website mentioned above. Lahey only sell through distributors and dealers. Both Lahey and Intel offer academic and multi-user pricing, and both are distributed by leading Fortran vendor Polyhedron, or, in Australia, by Devin Trussell of Computer Transition Systems.

Appropriate Versions of LF, LF90 and LF95

• We are aware of no problems with version 7 or version 7.1 of LF.
• We recommend version 5.70f of LF95. [We have found some problems with version 5.60. Programs compiled with version 5.60 may crash during LU decomposition if memory is tight. This does not happen with version 5.70.]
• We only support version 4.50i of LF90.
• The cut-down Lahey version, Essential Lahey Fortran 90 (ELF90), is not suitable for use with GEMPACK.

Get the latest Lahey maintenance update for your Fortran

You can download at no cost the latest Lahey maintenance update for your particular version of LF, LF95 or LF90. We recommend that you always work with the latest one available.

• Type "lf95 -ver" at command line to find out which version you have.
• If you have LF95 version 5.6 you must upgrade to latest version 5.6h.
• If you have LF95 version 5.7 you should upgrade to latest version 5.7f.
• More Lahey updates here.

F77L3 (Lahey Fortran 77, F77L3/EM-32)

• This can only be used with Release 7.0 or earlier of GEMPACK.
• This does not run under Windows XP.
• We recommend that users of F77L3 upgrade to LF Express, or (for GEMPACK 10 and later) the Intel compiler.

Sharing Header Array Files with Other GEMPACK Users

The binary files (including Header Array files) produced by the older compilers LF90 or F77L3 are not completely compatible with those produced using the modern Intel or LF and LF95 compilers. However GEMPACK programs convert between the old and new styles without any user intervention.

Unix PCs

A Fortran compiler usually comes with the operating system, or is an optional extra.