Things that are new in version 3.3




The recovery mechanism (designed and programmed by Jens Vollinga). It allows the making of a snapshot of the current configuration after the completion of a module and before the next module is read. If then the program is halted for whatever reason at a later stage, it can be restarted at the point of the last snapshot. Notice that this has not yet been tested and many different programs. Hence we would like to hear about your experiences with it. Because it involves making a copy of the current expression one needs to keep an eye on disk space.

    See:  -R option in the chapter on "Running FORM"
	      The section on "Checkpoints" in the chapter on "Modules"

It is now allowed to use environment variables and to define preprocessor variables in the setup file or the setup at the start of a program. The definition of a preprocessor variable is as all other variables in the setup without \# in the file and with \#: in the setup at the start of the program. One is not allowed to use the preprocessor variables and environment variables in the keywords of the setup. This limitation is due to the fact that when this is read FORM hasn't started completely and hence it does not possess all its capabilities yet.

	See:  Chapter on "The setup"

The DropCoefficient statement which sets the coefficient of the current term equal to one.

	See the DropCoefficient statement.

The statements

	Format FORTRAN90;
	Format FORTRAN90,string;

This prints the output in Fortran 90 mode with a {\tt &} character at the end of each line that has a continuation line. As in the regular Fortran modes numbers that are not clear integers are printed with a trailing period to force them to be floating point. When a string is given as in the second version of this statement, this string will be attached as in

   Format Fortran90,.0_ki;

which will give {\tt 2.0_ki/3.0_ki} in the output.

	See the Format statement.

The option to print only a certain fraction of the statistics. This is done with

   On FewerStatistics,20;

to print one out of every 20 statistics. One can of course put other integers there. If no integer is provided the default value is 10.

	See the On and Off statements.

The shuffle and stuffle statements. These support the packages for symbolic summation with in particular harmonic sums and related functions.

The denominators statement. Makes it a bit easier to deal with the built in denominator function.

The modulus statement has been redone completely. The old version was rather incomplete.

The intohide statement can save disk operations when big expressions have to be put into the hide system.

New setup parameter: HideSize.

Nasty bugs in various commands have been repaired, thanks to people sending high quality bug reports.

See also the remark at the end of the description of the replace_ function.

There are still some features that remain bothersome. For example the traffic jams at the disk when TFORM has to deal with many disk-to-disk sorts simultaneously. This is described in some of the extra documentation with some parameters one can play with to minimize its effects.