AskButtons (query)
AskButtons (query, button1, ...)
Asks a question and presents a list of buttons to the user (or
a menu of options in text mode). Returns the 1-based index of the button
pressed. That is, returns 1 if the first button was pressed, 2 if the second
button was pressed, and so on. If the user closes the window (or simply hits
enter in text mode), then null
is returned. The execution
of the program is blocked until the user responds.
Version 1.0.10 onwards.
AskString (query)
AskString (query, default)
Asks a question and lets the user enter a string, which
it then returns. If the user cancels or closes the window, then
null
is returned. The execution of the program
is blocked until the user responds. If default
is given, then it is pre-typed in for the user to just press enter on (version 1.0.6 onwards).
Compose (f,g)
Compose two functions and return a function that is the composition of f
and g
.
ComposePower (f,n,x)
Compose and execute a function with itself n
times, passing x
as argument. Returning x
if
n
equals 0.
Example:
genius>
function f(x) = x^2 ;
genius>
ComposePower (f,3,7)
= 5764801genius>
f(f(f(7)))
= 5764801
Evaluate (str)
Parses and evaluates a string.
GetCurrentModulo
Get current modulo from the context outside the function. That is, if outside of
the function was executed in modulo (using mod
) then this returns what
this modulo was. Normally the body of the function called is not executed in modular arithmetic,
and this builtin function makes it possible to make GEL functions aware of modular arithmetic.
Identity (x)
Identity function, returns its argument. It is equivalent to function Identity(x)=x
.
IntegerFromBoolean (bval)
Make integer (0 for false
or 1 for
true
) from a boolean value.
bval
can also be a number in which case a
non-zero value will be interpreted as true
and
zero will be interpreted as false
.
IsBoolean (arg)
Check if argument is a boolean (and not a number).
IsDefined (id)
Check if an id is defined. You should pass a string or and identifier. If you pass a matrix, each entry will be evaluated separately and the matrix should contain strings or identifiers.
IsFunction (arg)
Check if argument is a function.
IsFunctionOrIdentifier (arg)
Check if argument is a function or an identifier.
IsFunctionRef (arg)
Check if argument is a function reference. This includes variable references.
IsMatrix (arg)
Check if argument is a matrix. Even though null
is
sometimes considered an empty matrix, the function IsMatrix
does
not consider null
a matrix.
IsNull (arg)
Check if argument is a null
.
IsString (arg)
Check if argument is a text string.
IsValue (arg)
Check if argument is a number.
Parse (str)
Parses but does not evaluate a string. Note that certain pre-computation is done during the parsing stage.
SetFunctionFlags (id,flags...)
Set flags for a function, currently "PropagateMod"
and "NoModuloArguments"
.
If "PropagateMod"
is set, then the body of the function is evaluated in modular arithmetic when the function
is called inside a block that was evaluated using modular arithmetic (using mod
). If
"NoModuloArguments"
, then the arguments of the function are never evaluated using modular arithmetic.
SetHelp (id,category,desc)
Set the category and help description line for a function.
SetHelpAlias (id,alias)
Sets up a help alias.
chdir (dir)
Changes current directory, same as the cd.
CurrentTime
Returns the current UNIX time with microsecond precision as a floating point number. That is, returns the number of seconds since January 1st 1970.
Version 1.0.15 onwards.
display (str,expr)
Display a string and an expression with a colon to separate them.
DisplayVariables (var1,var2,...)
Display set of variables. The variables can be given as strings or identifiers. For example:
DisplayVariables(`x,`y,`z)
If called without arguments (must supply empty argument list) as
DisplayVariables()
then all variables are printed including a stacktrace similar to Show user variables in the graphical version.
Version 1.0.18 onwards.
error (str)
Prints a string to the error stream (onto the console).
exit
Aliases: quit
Exits the program.
false
Aliases: False
FALSE
The false
boolean value.
manual
Displays the user manual.
print (str)
Prints an expression and then print a newline. The argument str
can be any expression. It is
made into a string before being printed.
printn (str)
Prints an expression without a trailing newline. The argument str
can be any expression. It is
made into a string before being printed.
PrintTable (f,v)
Print a table of values for a function. The values are in the
vector v
. You can use the vector
building notation as follows:
PrintTable (f,[0:10])
If v
is a positive integer, then the table of
integers from 1 up to and including v will be used.
Version 1.0.18 onwards.
protect (id)
Protect a variable from being modified. This is used on the internal GEL functions to avoid them being accidentally overridden.
ProtectAll ()
Protect all currently defined variables, parameters and functions from being modified. This is used on the internal GEL functions to avoid them being accidentally overridden. Normally Genius Mathematics Tool considers unprotected variables as user defined.
Version 1.0.7 onwards.
set (id,val)
Set a global variable. The id
can be either a string or a quoted identifier.
For example:
set(`x,1)
will set the global variable x
to the value 1.
The function returns the val
, to be
usable in chaining.
SetElement (id,row,col,val)
Set an element of a global variable which is a matrix.
The id
can be either a string or a quoted identifier.
For example:
SetElement(`x,2,3,1)
will set the second row third column element of the global variable x
to the value 1. If no global variable of the name exists, or if it is set to something that's not a matrix, a new zero matrix of appropriate size will be created.
The row
and col
can also be ranges, and the semantics are the same as for regular setting of the elements with an equals sign.
The function returns the val
, to be
usable in chaining.
Available from 1.0.18 onwards.
SetElement (id,elt,val)
Set an element of a global variable which is a vector.
The id
can be either a string or a quoted identifier.
For example:
SetElement(`x,2,1)
will set the second element of the global vector variable x
to the value 1. If no global variable of the name exists, or if it is set to something that's not a vector (matrix), a new zero row vector of appropriate size will be created.
The elt
can also be a range, and the semantics are the same as for regular setting of the elements with an equals sign.
The function returns the val
, to be
usable in chaining.
Available from 1.0.18 onwards.
string (s)
Make a string. This will make a string out of any argument.
true
Aliases: True
TRUE
The true
boolean value.
undefine (id)
Alias: Undefine
Undefine a variable. This includes locals and globals, every value on all context levels is wiped. This function should really not be used on local variables. A vector of identifiers can also be passed to undefine several variables.
UndefineAll ()
Undefine all unprotected global variables
(including functions and parameters). Normally Genius Mathematics Tool
considers protected variables as system defined functions
and variables. Note that UndefineAll
only removes the global definition of symbols not local ones,
so that it may be run from inside other functions safely.
Version 1.0.7 onwards.
unprotect (id)
Unprotect a variable from being modified.
UserVariables ()
Return a vector of identifiers of user defined (unprotected) global variables.
Version 1.0.7 onwards.
wait (secs)
Waits a specified number of seconds. secs
must be non-negative. Zero is accepted and nothing happens in this case,
except possibly user interface events are processed.
Since version 1.0.18, secs
can be a noninteger number, so
wait(0.1)
will wait for one tenth of a second.
version
Returns the version of Genius as a horizontal 3-vector with major version first, then minor version and finally the patch level.
warranty
Gives the warranty information.