Miscellaneous Options
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Introduction to Miscellaneous Options
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In this section various options are discussed which have a global effect on the operation of maxima.   Also various lists such as the list of all user defined functions, are discussed.

SHARE
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- The SHARE directory on MC or on a DEC20 version of MACSYMA contains programs, information files, etc.  which are considered to be of interest to the MACSYMA community.  Most files on SHARE; are not part of the MACSYMA system per se and must be loaded individually by the user, e.g.  LOADFILE("array");. Many files on SHARE; were contributed by MACSYMA users.  Do PRINTFILE(SHARE,USAGE,SHARE); for more details and the conventions for contributing to the SHARE directory.  For an annotated "table of contents" of the directory, do: PRINTFILE(SHARE,>,SHARE);

Definitions for Miscellaneous Options
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 -- Variable: ALIASES
     default: [] atoms which have a user defined alias (set up by the ALIAS, ORDERGREAT, ORDERLESS functions or by DECLAREing the atom a NOUN).

 -- Variable: ALLSYM
     default: [TRUE] - If TRUE then all indexed objects are assumed symmetric in all of their covariant and contravariant indices. If FALSE then no symmetries of any kind are assumed in these indices. Derivative indices are always taken to be symmetric.

 -- declaration: ALPHABETIC
     Adds to MACSYMA's alphabet which initially contains the letters A-Z, % and _. Thus, DECLARE("~",ALPHABETIC) enables NEW~VALUE to be used as a name.

 -- Function: APROPOS (string)
     takes a character string as argument and looks at all the MACSYMA names for ones with that string appearing anywhere within them.  Thus, APROPOS(EXP); will return a long list of all the flags and functions which have EXP as part of their names, such as EXPAND, EXP, EXPONENTIALIZE.  Thus if you can only remember part of the name of something you can use this command to find the rest of the name. Similarily, you could say APROPOS(TR_); to find a list of many of the switches relating to the TRANSLATOR (most of which begin with TR_).

 -- Function: ARGS (exp)
     returns a list of the args of exp.  I.e. it is essentially equivalent to

          SUBSTPART("[",exp,0)

     Both ARGS and SUBSTPART depend on the setting of INFLAG.

 -- Function: DUMMY (i1,i2,...)
     will set each index i1,i2,... to name of the form !n where n is a positive integer.  This guarantees that dummy indices which are needed in forming expressions will not conflict with indices already in use.  COUNTER[default 1] determines the numerical suffix to be used in generating the next dummy index.  The prefix is determined by the option DUMMYX[!].

 -- Variable: GENINDEX
     default: [I] is the alphabetic prefix used to generate the next variable of summation when necessary.

 -- Variable: GENSUMNUM
     [0] is the numeric suffix used to generate the next variable of summation.  If it is set to FALSE then the index will consist only of GENINDEX with no numeric suffix.

 -- Variable: INF
     - real positive infinity.

 -- Variable: INFINITY
     - complex infinity, an infinite magnitude of arbitrary phase angle.  (See also INF and MINF.)

 -- Variable: INFOLISTS
     default: [] a list of the names of all of the information lists in MACSYMA. These are: LABELS - all bound C,D, and E labels. VALUES - all bound atoms, i.e. user variables, not MACSYMA Options or Switches, (set up by : , :: , or functional binding). FUNCTIONS - all user defined functions (set up by f(x):=...). ARRAYS - declared and undeclared arrays (set up by : , :: , or :=...) MACROS - any Macros defined by the user. MYOPTIONS - all options ever reset by the user (whether or not they get reset to their default value). RULES - user defined pattern matching and simplification rules (set up by TELLSIMP, TELLSIMPAFTER, DEFMATCH, or, DEFRULE.) ALIASES - atoms which have a user defined alias (set up by the ALIAS, ORDERGREAT, ORDERLESS functions or by DECLAREing the atom a NOUN). DEPENDENCIES - atoms which have functional dependencies (set up by the DEPENDS or GRADEF functions). GRADEFS - functions which have user defined derivatives (set up by the GRADEF function). PROPS - atoms which have any property other than those mentioned above, such as atvalues, matchdeclares, etc.  as well as properties specified in the DECLARE function. LET_RULE_PACKAGES - a list of all the user-defined let rule packages plus the special package DEFAULT_LET_RULE_PACKAGE. (DEFAULT_LET_RULE_PACKAGE is the name of the rule package used when one is not explicitly set by the user.)

 -- Function: INTEGERP (exp)
     is TRUE if exp is an integer else FALSE.

 -- Variable: M1PBRANCH
     default: [FALSE] - "principal branch for -1 to a power". Quantities such as (-1)^(1/3) [i.e. "odd" rational exponent] and (-1)^(1/4) [i.e. "even" rational exponent] are now handled as indicated in the following chart:

                       DOMAIN:REAL(default)

          (-1)^(1/3):      -1
          (-1)^(1/4):   (-1)^(1/4)

                          DOMAIN:COMPLEX
          M1PBRANCH:FALSE(default)   M1PBRANCH:TRUE
          (-1)^(1/3)               1/2+%i*sqrt(3)/2
          (-1)^(1/4)              sqrt(2)/2+%i*sqrt(2)/2

 -- Function: NUMBERP (exp)
     is TRUE if exp is an integer, a rational number, a floating point number or a bigfloat else FALSE.

 -- Function: PROPERTIES (a)
     will yield a list showing the names of all the properties associated with the atom a.

 -- special symbol: PROPS
     - atoms which have any property other than those explicitly mentioned in INFOLISTS, such as atvalues, matchdeclares, etc. as well as properties specified in the DECLARE function.

 -- Function: PROPVARS (prop)
     yields a list of those atoms on the PROPS list which have the property indicated by prop.  Thus PROPVARS(ATVALUE) will yield a list of atoms which have atvalues.

 -- Function: PUT (a, p, i)
     associates with the atom a the property p with the indicator i.  This enables the user to give an atom any arbitrary property.

 -- Function: QPUT (a, p, i)
     is similar to PUT but it doesn't have its arguments evaluated.

 -- Function: REM (a, i)
     removes the property indicated by i from the atom a.

 -- Function: REMOVE (args)
     will remove some or all of the properties associated with variables or functions. REMOVE(a1, p1, a2, p2, ...)  removes the property pi from the atom ai. Ai and pi may also be lists as with DECLARE.  Pi may be any property e.g.  FUNCTION, MODE_DECLARE, etc.  It may also be TRANSFUN implying that the translated LISP version of the function is to be removed. This is useful if one wishes to have the MACSYMA version of the function executed rather than the translated version. Pi may also be OP or OPERATOR to remove a syntax extension given to ai (see Appendix II).  If ai is "ALL" then the property indicated by pi is removed from all atoms which have it.  Unlike the more specific remove functions (REMVALUE, REMARRAY, REMFUNCTION, and REMRULE) REMOVE does not indicate when a given property is non-existent; it always returns "DONE".

 -- Function: REMVALUE (name1, name2, ...)
     removes the values of user variables (which can be subscripted) from the system.  If name is ALL then the values of all user variables are removed.  Values are those items given names by the user as opposed to those which are automatically labeled by MACSYMA as Ci, Di, or Ei.

 -- Function: RENAME (exp)
     returns an expression equivalent to exp but with the dummy indices in each term chosen from the set [!1,!2,...].  Each dummy index in a product will be different; for a sum RENAME will try to make each dummy index in a sum the same.  In addition, the indices will be sorted alphanumerically.

 -- Function: RNCOMBINE (exp)
     transforms exp by combining all terms of exp that have identical denominators or denominators that differ from each other by numerical factors only.  This is slightly different from the behavior of COMBINE, which collects terms that have identical denominators. Setting PFEFORMAT:TRUE and using COMBINE will achieve results similar to those that can be obtained with RNCOMBINE, but RNCOMBINE takes the additional step of cross-multiplying numerical denominator factors. This results in neater forms, and the possiblity of recognizing some cancellations.  Bugs to ASB.

 -- Function: SCALARP (exp)
     is TRUE if exp is a number, constant, or variable DECLAREd SCALAR, or composed entirely of numbers, constants, and such variables, but not containing matrices or lists.

 -- Function: SCALEFACTORS (coordinatetransform)
     Here coordinatetransform evaluates to the form [[expression1, expression2, ...], indeterminate1, indeterminat2, ...], where indeterminate1, indeterminate2, etc. are the curvilinear coordinate variables and where a set of rectangular Cartesian components is given in terms of the curvilinear coordinates by [expression1, expression2, ...]. COORDINATES is set to the vector [indeterminate1, indeterminate2,...], and DIMENSION is set to the length of this vector.  SF[1], SF[2], ..., SF[DIMENSION] are set to the coordinate scale factors, and SFPROD is set to the product of these scale factors.  Initially, COORDINATES is [X, Y, Z], DIMENSION is 3, and SF[1]=SF[2]=SF[3]=SFPROD=1, corresponding to 3-dimensional rectangular Cartesian coordinates. To expand an expression into physical components in the current coordinate system, there is a function with usage of the form

 -- Function: SETUP_AUTOLOAD (file,func1,...,funcN)
     which takes two or more arguments: a file specification, and one or more function names, "funcI", and which indicates that if a call to "funcI" is made and "funcI" is not defined, that the file specified by "file" is to be automatically loaded in via LOAD, which file should contain a definition for "funcI".  (This is the process by which calling e.g. INTEGRATE in a fresh MACSYMA causes various files to be loaded in.) As with the other file-handling commands in MACSYMA, the arguments to SETUP_AUTOLOAD are not evaluated. Example: SETUP_AUTOLOAD("bessel")$ J1(0.0); . Note: SETUP_AUTOLOAD does not work for array functions.