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3 Help


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3.1 Documentation

The Maxima on-line user’s manual can be viewed in different forms. From the Maxima interactive prompt, the user’s manual is viewed as plain text by the ? command (i.e., the describe function). The user’s manual is viewed as info hypertext by the info viewer program and as a web page by any ordinary web browser.

example displays examples for many Maxima functions. For example,

(%i1) example (integrate);

yields

(%i2) test(f):=block([u],u:integrate(f,x),ratsimp(f-diff(u,x)))
(%o2) test(f) := block([u], u : integrate(f, x),
                                         ratsimp(f - diff(u, x)))
(%i3) test(sin(x))
(%o3)                           0
(%i4) test(1/(x+1))
(%o4)                           0
(%i5) test(1/(x^2+1))
(%o5)                           0

and additional output.

Categories:  Console interaction


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3.2 Functions and Variables for Help

Function: apropos (string)

Searches for Maxima names which have string appearing anywhere within them. Thus, apropos (exp) returns a list of all the flags and functions which have exp as part of their names, such as expand, exp, and 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. Similarly, you could say apropos (tr_) to find a list of many of the switches relating to the translator, most of which begin with tr_.

apropos("") returns a list with all Maxima names.

apropos returns the empty list [], if no name is found.

Example:

Show all Maxima symbols which have "gamma" in the name:

(%i1) apropos("gamma");
(%o1) [%gamma, gamma, gammalim, gamma_expand, gamma_incomplete_lower, 
gamma_incomplete, gamma_incomplete_generalized, 
gamma_incomplete_regularized, Gamma, log_gamma, makegamma, 
prefer_gamma_incomplete, gamma-incomplete, 
gamma_incomplete_generalized_regularized]

Categories:  Help

Function: demo (filename)

Evaluates Maxima expressions in filename and displays the results. demo pauses after evaluating each expression and continues after the user enters a carriage return. (If running in Xmaxima, demo may need to see a semicolon ; followed by a carriage return.)

demo searches the list of directories file_search_demo to find filename. If the file has the suffix dem, the suffix may be omitted. See also file_search.

demo evaluates its argument. demo returns the name of the demonstration file.

Example:

(%i1) demo ("disol");

batching /home/wfs/maxima/share/simplification/disol.dem
 At the _ prompt, type ';' followed by enter to get next demo
(%i2)                      load("disol")

_
(%i3)           exp1 : a (e (g + f) + b (d + c))
(%o3)               a (e (g + f) + b (d + c))

_
(%i4)                disolate(exp1, a, b, e)
(%t4)                         d + c

(%t5)                         g + f

(%o5)                   a (%t5 e + %t4 b)

_

Function: describe
    describe (string)
    describe (string, exact)
    describe (string, inexact)

describe(string) is equivalent to describe(string, exact).

describe(string, exact) finds an item with title equal (case-insensitive) to string, if there is any such item.

describe(string, inexact) finds all documented items which contain string in their titles. If there is more than one such item, Maxima asks the user to select an item or items to display.

At the interactive prompt, ? foo (with a space between ? and foo) is equivalent to describe("foo", exact), and ?? foo is equivalent to describe("foo", inexact).

describe("", inexact) yields a list of all topics documented in the on-line manual.

describe quotes its argument. describe returns true if some documentation is found, otherwise false.

See also Documentation.

Example:

(%i1) ?? integ
 0: Functions and Variables for Elliptic Integrals
 1: Functions and Variables for Integration
 2: Introduction to Elliptic Functions and Integrals
 3: Introduction to Integration
 4: askinteger  (Functions and Variables for Simplification)
 5: integerp  (Functions and Variables for Miscellaneous Options)
 6: integer_partitions  (Functions and Variables for Sets)
 7: integrate  (Functions and Variables for Integration)
 8: integrate_use_rootsof  (Functions and Variables for
    Integration)
 9: integration_constant_counter  (Functions and Variables for
    Integration)
 10: nonnegintegerp  (Functions and Variables for linearalgebra)
Enter space-separated numbers, `all' or `none': 7 8

 -- Function: integrate (<expr>, <x>)
 -- Function: integrate (<expr>, <x>, <a>, <b>)
     Attempts to symbolically compute the integral of <expr> with
     respect to <x>.  `integrate (<expr>, <x>)' is an indefinite
     integral, while `integrate (<expr>, <x>, <a>, <b>)' is a
     definite integral, [...]
     
 -- Option variable: integrate_use_rootsof
     Default value: `false'

     When `integrate_use_rootsof' is `true' and the denominator of
     a rational function cannot be factored, `integrate' returns
     the integral in a form which is a sum over the roots (not yet
     known) of the denominator.
     [...]

In this example, items 7 and 8 were selected (output is shortened as indicated by [...]). All or none of the items could have been selected by entering all or none, which can be abbreviated a or n, respectively.

Categories:  Help Console interaction

Function: example
    example (topic)
    example ()

example (topic) displays some examples of topic, which is a symbol or a string. To get examples for operators like if, do, or lambda the argument must be a string, e.g. example ("do"). example is not case sensitive. Most topics are function names.

example () returns the list of all recognized topics.

The name of the file containing the examples is given by the global option variable manual_demo, which defaults to "manual.demo".

example quotes its argument. example returns done unless no examples are found or there is no argument, in which case example returns the list of all recognized topics.

Examples:

(%i1) example(append);
(%i2) append([y+x,0,-3.2],[2.5e+20,x])
(%o2)             [y + x, 0, - 3.2, 2.5e+20, x]
(%o2)                         done
(%i3) example("lambda");
(%i4) lambda([x,y,z],x^2+y^2+z^2)
                                    2    2    2
(%o4)            lambda([x, y, z], x  + y  + z )
(%i5) %(1,2,a)
                              2
(%o5)                        a  + 5
(%i6) 1+2+a
(%o6)                         a + 3
(%o6)                         done

Categories:  Help Console interaction

Option variable: manual_demo

Default value: "manual.demo"

manual_demo specifies the name of the file containing the examples for the function example. See example.

Categories:  Help Global variables


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