108 lines
		
	
	
		
			4.9 KiB
		
	
	
	
		
			Factor
		
	
	
			
		
		
	
	
			108 lines
		
	
	
		
			4.9 KiB
		
	
	
	
		
			Factor
		
	
	
USING: help.markup help.syntax math sequences ;
 | 
						|
IN: math.polynomials
 | 
						|
 | 
						|
ARTICLE: "polynomials" "Polynomials"
 | 
						|
"A polynomial is a vector with the highest powers on the right:"
 | 
						|
{ $code "{ 1 1 0 1 } -> 1 + x + x^3" "{ } -> 0" }
 | 
						|
"Numerous words are defined to help with polynomial arithmetic:"
 | 
						|
{ $subsections
 | 
						|
    p=
 | 
						|
    p+
 | 
						|
    p-
 | 
						|
    p*
 | 
						|
    p-sq
 | 
						|
    powers
 | 
						|
    n*p
 | 
						|
    p/mod
 | 
						|
    pgcd
 | 
						|
    polyval
 | 
						|
    pdiff
 | 
						|
    pextend-conv
 | 
						|
    ptrim
 | 
						|
    2ptrim
 | 
						|
} ;
 | 
						|
 | 
						|
ABOUT: "polynomials"
 | 
						|
 | 
						|
HELP: powers
 | 
						|
{ $values { "n" integer } { "x" number } { "seq" sequence } }
 | 
						|
{ $description "Output a sequence having " { $snippet "n" } " elements in the format: " { $snippet "{ 1 x x^2 x^3 ... }" } "." }
 | 
						|
{ $examples { $example "USING: math.polynomials prettyprint ;" "4 2 powers ." "{ 1 2 4 8 }" } } ;
 | 
						|
 | 
						|
HELP: p=
 | 
						|
{ $values { "p" "a polynomial" } { "q" "a polynomial" } { "?" "a boolean" } }
 | 
						|
{ $description "Tests if two polynomials are equal." }
 | 
						|
{ $examples { $example "USING: math.polynomials prettyprint ;" "{ 0 1 } { 0 1 0 } p= ." "t" } } ;
 | 
						|
 | 
						|
HELP: ptrim
 | 
						|
{ $values { "p" "a polynomial" } { "p" "a polynomial" } }
 | 
						|
{ $description "Trims excess zeros from a polynomial." }
 | 
						|
{ $examples { $example "USING: math.polynomials prettyprint ;" "{ 0 1 0 0 } ptrim ." "{ 0 1 }" } } ;
 | 
						|
 | 
						|
HELP: 2ptrim
 | 
						|
{ $values { "p" "a polynomial" } { "q" "a polynomial" } { "p" "a polynomial" } { "q" "a polynomial" } }
 | 
						|
{ $description "Trims excess zeros from two polynomials." }
 | 
						|
{ $examples { $example "USING: kernel math.polynomials prettyprint ;" "{ 0 1 0 0 } { 1 0 0 } 2ptrim [ . ] bi@" "{ 0 1 }\n{ 1 }" } } ;
 | 
						|
 | 
						|
HELP: p+
 | 
						|
{ $values { "p" "a polynomial" } { "q" "a polynomial" } { "r" "a polynomial" } }
 | 
						|
{ $description "Adds " { $snippet "p" } " and " { $snippet "q" } " component-wise." }
 | 
						|
{ $examples { $example "USING: math.polynomials prettyprint ;" "{ 1 0 1 } { 0 1 } p+ ." "{ 1 1 1 }" } } ;
 | 
						|
 | 
						|
HELP: p-
 | 
						|
{ $values { "p" "a polynomial" } { "q" "a polynomial" } { "r" "a polynomial" } }
 | 
						|
{ $description "Subtracts " { $snippet "q" } " from " { $snippet "p" } " component-wise." }
 | 
						|
{ $examples { $example "USING: math.polynomials prettyprint ;" "{ 1 1 1 } { 0 1 } p- ." "{ 1 0 1 }" } } ;
 | 
						|
 | 
						|
HELP: n*p
 | 
						|
{ $values { "n" number } { "p" "a polynomial" } { "n*p" "a polynomial" } }
 | 
						|
{ $description "Multiplies each element of " { $snippet "p" } " by " { $snippet "n" } "." }
 | 
						|
{ $examples { $example "USING: math.polynomials prettyprint ;" "4 { 3 0 1 } n*p ." "{ 12 0 4 }" } } ;
 | 
						|
 | 
						|
HELP: pextend-conv
 | 
						|
{ $values { "p" "a polynomial" } { "q" "a polynomial" } { "p" "a polynomial" } { "q" "a polynomial" } }
 | 
						|
{ $description "Convulution, extending to " { $snippet "p_m + q_n - 1" } "." }
 | 
						|
{ $examples { $example "USING: kernel math.polynomials prettyprint ;" "{ 1 0 1 } { 0 1 } pextend-conv [ . ] bi@" "V{ 1 0 1 0 }\nV{ 0 1 0 0 }" } } ;
 | 
						|
 | 
						|
HELP: p*
 | 
						|
{ $values { "p" "a polynomial" } { "q" "a polynomial" } { "r" "a polynomial" } }
 | 
						|
{ $description "Multiplies two polynomials." }
 | 
						|
{ $examples { $example "USING: math.polynomials prettyprint ;" "{ 1 2 3 0 0 0 } { 1 2 0 0 } p* ." "{ 1 4 7 6 0 0 0 0 0 }" } } ;
 | 
						|
 | 
						|
HELP: p-sq
 | 
						|
{ $values { "p" "a polynomial" } { "p^2" "a polynomial" } }
 | 
						|
{ $description "Squares a polynomial." }
 | 
						|
{ $examples { $example "USING: math.polynomials prettyprint ;" "{ 1 2 0 } p-sq ." "{ 1 4 4 0 0 }" } } ;
 | 
						|
 | 
						|
HELP: p/mod
 | 
						|
{ $values { "p" "a polynomial" } { "q" "a polynomial" } { "z" "a polynomial" } { "w" "a polynomial" } }
 | 
						|
{ $description "Computes to quotient " { $snippet "z" } " and remainder " { $snippet "w" } " of dividing " { $snippet "p" } " by " { $snippet "q" } "." }
 | 
						|
{ $examples { $example "USING: kernel math.polynomials prettyprint ;" "{ 1 1 1 1 } { 3 1 } p/mod [ . ] bi@" "V{ 7 -2 1 }\nV{ -20 0 0 }" } } ;
 | 
						|
 | 
						|
HELP: pgcd
 | 
						|
{ $values { "p" "a polynomial" } { "q" "a polynomial" } { "a" "a polynomial" } { "d" "a polynomial" } }
 | 
						|
{ $description "Computes the greatest common divisor " { $snippet "d" } " of " { $snippet "p" } " and " { $snippet "q" } ", and another value " { $snippet "a" } " satisfying:" { $code "a*q = d mod p" } }
 | 
						|
{ $notes "GCD in the case of polynomials is a monic polynomial of the highest possible degree that divides into both " { $snippet "p" } " and " { $snippet "q" } "." }
 | 
						|
{ $examples
 | 
						|
    { $example "USING: kernel math.polynomials prettyprint ;"
 | 
						|
               "{ 1 1 1 1 } { 1 1 } pgcd [ . ] bi@"
 | 
						|
               "{ 0 0 }\n{ 1 1 }"
 | 
						|
    }
 | 
						|
} ;
 | 
						|
 | 
						|
HELP: pdiff
 | 
						|
{ $values { "p" "a polynomial" } { "p'" "a polynomial" } }
 | 
						|
{ $description "Finds the derivative of " { $snippet "p" } "." } ;
 | 
						|
 | 
						|
HELP: polyval
 | 
						|
{ $values { "x" number } { "p" "a polynomial" } { "p[x]" number } }
 | 
						|
{ $description "Evaluate " { $snippet "p" } " with the input " { $snippet "x" } "." }
 | 
						|
{ $examples { $example "USING: math.polynomials prettyprint ;" "2 { 1 0 1 } polyval ." "5" } } ;
 | 
						|
 | 
						|
HELP: polyval*
 | 
						|
{ $values { "p" "a literal polynomial" } }
 | 
						|
{ $description "Macro version of " { $link polyval } ". Evaluates the literal polynomial " { $snippet "p" } " at the value off the top of the stack." }
 | 
						|
{ $examples { $example "USING: math.polynomials prettyprint ;" "2 { 1 0 1 } polyval* ." "5" } } ;
 | 
						|
 | 
						|
{ polyval polyval* } related-words
 |