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You can browse the scripts available in this addon using Trac.


Use JAL/Package Manager.

Load the individual scripts in the addon as follows:

load 'math/misc/name_of_script'


amoeba 1.0.0 Nelder-Mead multi-dimensional minimization, aka the amoeba method
bigpi 1.0.0 Calculate several digits of pi
brent 1.0.0 Brent's method in J
contfrac 1.0.0 Continued fraction utilities
det 1.0.0 Definitions for determinants
fermat 1.0.0 Fermat factorization
gamesolver 1.0.0 Find optimal mixed strategies for 2-person games
gcd 1.0.0 Calculate GCD
integer 1.0.0 Various integer definitions
integrat 1.0.0 Various methods for numeric integration
jacobi 1.0.0 Jacobi's method for eigenvalues and vectors
legendre 1.0.0 Legendre symbol and quadratic residues
linear 1.0.0 Solve linear equations
makemat 1.0.0 Make various matrices
matfacto 1.0.0 Matrix factorization
mathutil 1.0.0 Math utilities
matutil 1.0.0 Matrix utilities
mean 1.0.0 Various means
numbers 1.0.0 Various number definitions
pollard 1.0.0 Pollard factorizations
poly 1.0.0 Polynomial functions
primutil 1.0.0 Primes - prime testing programs
quatern 1.0.0 Definitions for quaternions
rsa 1.0.0 RSA encryption
simplex 1.0.0 Simplex method
simplexnr 1.0.0 Simplex method
spline 1.0.0 Spline utilities
svd 1.0.0 Singular value decomposition


Nelder-Mead multi-dimensional minimization, aka the amoeba method

Henry H. Rich, October 2009

amoeba c Nelder-Mead multi-dimensional minimization


Calculate several digits of pi

from Borwein

bigpi v Calculate pi to different levels of of precision


Brent's method in J

(from J. Patrick Harrington)

brent a Adverb to solve f(x) = y0 by Brent's method.


Continued fraction utilities

contfrac v create continued fraction
contfracx v expand continued fraction


Definitions for determinants

det v Determinants of a matrix by recursive expansion of minors
detm v Determinants of square matrix by Gauss elimination


Fermat factorization

fermatfactor v Find factor of n near square root of n using Fermat's method


Find optimal mixed strategies for 2-person games

Henry H. Rich (, April 2005

solvegame v Find optimal mixed strategies for 2-person games


Calculate GCD

gcd v Greatest common denominator


Various integer definitions

inta v Augmented integers
inte v Extended integers
ints v Symmetric integers
intm v Minus integers
intn v Normal integers
intr v Reflexive integers
jint v Complex integers
jints c symmetric ints


Various methods for numeric integration

integrate c Numeric integration by Aitken extrapolation on Gauss integrals
simpson c Numeric integration by Simpson's method
adapt c Numeric integration by adaptive quadrature


Jacobi's method for eigenvalues and vectors

jacobi v Calculate eigenvalues and vectors using Jacobi's method


Legendre symbol and quadratic residues

quadres v Quadratic residues of p
quadrec v Quadratic reciprocity
legendre v Legendre symbol (n/p) for integer n, odd prime p


Solve linear equations

gauss_elimination v Gauss elimination (partial pivoting)
gauss_jordan v Gauss-Jordan elimination (full pivoting)
gauss_seidel v Solves Ax=B for matrix A, vector B
jacobi_iteration v Solves Ax=B for matrix A, vector B


Make various matrices

bandmat v Band matrix in position x from diagonal y
cidmat v Counter identity matrix of size y
diagmat v Diagonal matrix with y on diagonal
hilbertmat v Hilbert matrix of size y
ltmat v Lower triangular matrix (of 1's) of size y
utmat v Upper triangular matrix (of 1's) of size y


Matrix factorization

choleski v Choleski decomposition of matrix y
lud v LU decomposition of matrix y
qrd v QR decomposition of matrix y


Math utilities

det v Determinant of matrix y
mp v Matrix product of x and y
powermod a x (n powermod) y computes n|x^y
randomint v Random integer in range 0, <: 10^y
randomintd v Random integer with y digits
timesmod a x (n timesmod) y computes n|x*y


Matrix utilities

diag v Diagonal of matrix
invsut v Invert square upper-triangular matrix
minors v minors of matrix
band v b band M - zero all but x bands of matrix y
cond v Condition number of matrix
pivot v Pivot at row, column
coldrop v Drop cols from M
coltake v Take cols from M
rowdrop v Drop rows from M
rowtake v Take rows from M
rowswap v Swap rows i and j
rowscale v Multiply row i by n
rowshear v Multiply row j by n and add to row i


Various means

arithmean v Arithmetic mean of y
geomean v Geometric mean of y
harmean v Harmonic mean of y
commonmean v Common mean of y


Various number definitions

bell v Number of ways of partitioning y things into subsets
bernoulli v Bernoulli numbers from 0 to y
catalan v Catalan numbers
cycles v Table of Stirling cycle numbers (S1)
cycle v Number of ways of partitioning n items into k cycles
eulers v Table of Eulerian numbers
euler v Number of permutations of size n with k ascents
fermat v Fermat numbers
fibonacci v first y+1 Fibonacci numbers
lucas v first y+1 Lucas numbers
fibbinet v Calculates nth Fibonacci number using Binet formula
subsets v Table of Stirling subset numbers (S2)
subset v Number of ways of partitioning n items into k sets
tangent v tangent numbers from 0 to y


Pollard factorizations

pollardrho v Pollard rho factorization
pollardpm1 v Pollard p-1 factorizaton


Polynomial functions

chebyshev_tp v Evaluate Chebyshev T polynomial of order n at x
chebyshev_up v Evaluate Chebyshev U polynomial of order n at x
chebyshev_tpc v Returns coefficients of Chebyshev T polynomial of order n
chebyshev_upc v Returns coefficients of Chebyshev U polynomial of order n
legendre_pc v Returns coefficients of legendre polynomial of order n


Primes - prime testing programs

prevprime v Previous prime number to y
nextprime v Next prime number after y
primeq v Test for prime
primesto v Primes up to y
carmichaelq v Test composite for Carmichael number
inversep v Inverse mod p
mersenneq v Test if prime p generates a mersenne prime
primepowersto v Generate prime powers up to y
smallprimefactors v Get small primefactors from number


Definitions for quaternions

real quaternions:

- stored as real arrays with last dimension of length 4

qncon v Conjugate
qnmul v Multiplication
qnrec v Reciprocal
qndivl v Division (left quotient)
qndivr v Division (right quotient)
qndivml v Division (using matrix divide, left quotient)
qndivmr v Division (using matrix divide, right quotient)
qnpolar v Convert to/from polar form


RSA encryption


P & Q are primes
E is exponent, relatively prime to (P-1)*(Q-1)
D is the inverse of E mod (P-1)*(Q-1)


the public key is: PQ,E (i.e. a pair of numbers)
the private key is: D


msg (PQ powermod) E encodes msg
msg (PQ powermod) D decodes msg


Simplex method

see also math/misc/simplexnr for the simplex method following
"Numerical Recipes in C"

example description thanks to Henry H. Rich

simplex v Simplex method


Simplex method

see also math/misc/simplex

This implementation follows Numerical Recipes in C, 2/e,
section 10.8, except that we let the user specify the type of
each constraint rather than expecting the order <: >: =
and we use a similar but refined way of handling degenerate pivots

Henry H. Rich (, June 2001

simplexnr v Run simplex method


Spline utilities

cubicspline v Calculate cubic spline
interspline v Interpolate spline
freespline v Calculate spline
aprxspline v Approximate by spline


Singular value decomposition

for real matrices only

svd v Singular value decomposition of matrix y