Maple Professional
Maple Academic
Maple Student Edition
Maple Personal Edition
Maple Player
Maple Player for iPad
MapleSim Professional
MapleSim Academic
Maple T.A. - Testing & Assessment
Maple T.A. MAA Placement Test Suite
Möbius - Online Courseware
Machine Design / Industrial Automation
Aerospace
Vehicle Engineering
Robotics
Power Industries
System Simulation and Analysis
Model development for HIL
Plant Modeling for Control Design
Robotics/Motion Control/Mechatronics
Other Application Areas
Mathematics Education
Engineering Education
High Schools & Two-Year Colleges
Testing & Assessment
Students
Financial Modeling
Operations Research
High Performance Computing
Physics
Live Webinars
Recorded Webinars
Upcoming Events
MaplePrimes
Maplesoft Blog
Maplesoft Membership
Maple Ambassador Program
MapleCloud
Technical Whitepapers
E-Mail Newsletters
Maple Books
Math Matters
Application Center
MapleSim Model Gallery
User Case Studies
Exploring Engineering Fundamentals
Teaching Concepts with Maple
Maplesoft Welcome Center
Teacher Resource Center
Student Help Center
codegen[JACOBIAN] - compute the JACOBIAN matrix of a Maple procedure
Calling Sequence
JACOBIAN(F)
JACOBIAN(F, X)
JACOBIAN(F, X, ...)
Parameters
F
-
list of Maple procedures
X
list of symbols
Description
The first argument F is a list of Maple procedures f1,f2,...,fm which compute functions of x1,x2,...,xn. The JACOBIAN command outputs a new procedure which when executed at given values for x1,x2,...,xn, returns a matrix J of the partial derivatives at the given values where . For example, given
f := proc(x, y) y^2*exp(-x) end proc;
g := proc(x, y) x*y*exp(-x) end proc;
the output of J := JACOBIAN([f,g]); is the procedure
proc(x, y) local df, dfr0, grd, t1, t2;
t1 := y^2;
t2 := exp(-x);
df := array(1 .. 2);
dfr0 := array(1 .. 4);
df[2] := t1;
df[1] := t2;
dfr0[2] := x*y;
grd := array(1 .. 2, 1 .. 2);
grd[1, 1] := -df[2]*exp(-x);
grd[1, 2] := 2*df[1]*y;
grd[2, 1] := y*t2 - dfr0[2]*exp(-x);
grd[2, 2] := x*t2;
return grd
end proc
The J procedure can be optimized by optimize(J). When J is called with inputs , it outputs the matrix
The JACOBIAN code is constructed by applying the joinprocs command to the procedures F then applying the GRADIENT command. The GRADIENT command uses automatic differentiation. See codegen[GRADIENT] for details. The remaining arguments to JACOBIAN are optional, they are described below.
By default, JACOBIAN computes the partial derivatives of all procedures in F w.r.t. all the parameters present in F[1]. The optional argument X, a list of symbols, may be used to specify which parameters to take the derivative w.r.t.
Two algorithms are supported, the so-called forward and reverse modes. By default, JACOBIAN tries to use the reverse mode since it usually leads to a more efficient code. If it is unable to use the reverse mode, the forward mode is used. The user may specify which algorithm is to be used by giving the optional argument mode=forward or mode=reverse.
The matrix of partial derivatives is, by default, returned as an array. The optional argument result_type=list, result_type=array, or result_type=seq specifies that the matrix of derivatives returned is to be a Maple list, array, and sequence respectively.
The command with(codegen,JACOBIAN) allows the use of the abbreviated form of this command.
Examples
f := proc(x,y) x*y^2 end proc;
g := proc(x,y) x^2*y end proc;
See Also
codegen[GRADIENT], codegen[joinprocs], codegen[optimize]
Download Help Document