Support

The SINGULAR Team provides free support.

Release

February 2010: Release of SINGULAR version 3-1-1. More

Jenks Prize

July 2004: The Richard D. Jenks Prize for Excellence in Software Engineering for Computer Algebra was awarded to the Singular team. More

Book: "A Singular Introduction to Commutative Algebra"

SINGULAR Examples

algebraic dependence, 87
annihilator, 186
Betti numbers, 135
- graded, 137
classification of singularities, 493
computation
- in fields, 5
- in polynomial rings, 7
- in quotient rings, 25
- of d(I,K[x]), 222
- of Hom, 106
- of the dimension, 211
- of Tor, 340
computing with radicals, 27
counting nodes, 489
creating ring maps, 8
cyclic decomposition, 159
deformation of singularities, 495
degree, 289
- of projection, 469
- of projective variety, 478
diagonal form, 154
dimension, 289
- embedding, 304
- of a module, 302
elimination
- and resultant, 431
- of module components, 180
- of variables, 71
- projective, 466
equidimensional
- decomposition, 263
- part, 261
estimating the determinacy, 491
finite maps, 196
finiteness test, 324
Fitting ideal, 186, 345
flat locus, 356
flatness test, 369
flattening stratification, 352
global versus local rings, 35
graded
- Betti numbers, 137
- rings and modules, 116
highest corner, 60
Hilbert
- function, 289
- polynomial, 299
Hilbert-Poincare series, 282
homogeneous resolution, 137
ideal membership, 68
image of module homomorphism, 99
independent set, 220
initial ideal, 299
injective, 420
integral
- closure of an ideal, 202
- elements, 195
intersection
- of ideals, 79
- of submodules, 102, 181
inverse of a power series, 316
Jacobian criterion, 304
Jordan normal form, 163
kernel
- of a ring map, 85
- of module homomorphism, 99, 187
Koszul complex, 378
leading data, 11
linear combination of ideal members, 68
local and global dimension, 472
lying over theorem, 225
maps induced by Hom, 96
matrix operations, 94
Milnor and Tjurina number, 488
minimal
- associated primes, 209
- presentations, 109
module
- annihilator, 186
- membership, 178
- presentation of, 104
- quotient, 102
- radical and zerodivisors, 184
monomial orderings, 16
morphisms of projective varieties, 455
multiplicity, 480
Noether normalization, 216
non-normal locus, 232
normal form, 51, 123
normalization, 230
Poincare series, 299
presentation of a module, 104
primary
- decomposition, 258
- test, 252
projective
- closure, 443
- elimination, 466
- Nullstellensatz, 437
- subschemes, 446
properties of ring maps, 20
quotient
- of ideals, 81
- of submodules, 102, 183
radical, 184, 265
- membership, 78
realization of rings, 42
reduction to zero-dimensional case, 257
regular
- sequences, 372
- system of parameters, 304
regularity test, 400
resolution, 135
- homogeneous, 137
saturation, 83, 446
Schreyer resolution, 150
singular locus, 309
solving equations, 76
- linear, 189
standard bases, 59, 124
subalgebra membership, 87
submodules, 104
- intersection of, 102, 181
- of An, 98
sum of submodules, 102
surface plot, 407, 413
surjective, 420
syzygies, 141
tangent cone, 480
tensor product
- of maps, 170
- of modules, 172
- of rings, 175
test
- for Cohen-Macaulayness, 386, 392, 394
- for flatness, 354
- for local freeness, 347
Weierstrass polynomial, 321
Zariski closure of the image, 74
zero-dimensional primary decomposition, 253
zerodivisors, 184
z-general power series, 320