Support Vector Machines - 5.2 English - 68552

AOCL API Guide (68552)

Document ID
68552
Release Date
2025-12-29
Version
5.2 English

The following options are supported.

Table 4.11 Table of Options for Support Vector Machines.#

Option name

Type

Default

Description

Constraints

tau

real

\(r=\varepsilon\)

Numerical stability parameter used in working set selection when kernel is not positive semi definite.

\(0 \le r\)

kernel

string

\(s=\) rbf

Kernel function to use for the calculations.

\(s=\) linear, poly, polynomial, rbf, or sigmoid.

storage order

string

\(s=\) column-major

Whether data is supplied and returned in row- or column-major order.

\(s=\) c, column-major, f, fortran, or row-major.

n_folds

integer

\(i=5\)

Number of folds to use with cross validation. Only used when predict probabilities is enabled.

\(1 \le i\)

check data

string

\(s=\) no

Check input data for NaNs prior to performing computation.

\(s=\) no, or yes.

cache size

real

\(r=-1\)

Size of the kernel cache in MB. The default value is -1.0 which automatically sets it to a value which will enable storage of the sampled kernel matrix. Increasing value of this option will result in faster training time.

\(-1 \le r\)

degree

integer

\(i=3\)

Parameter for ‘polynomial’ kernel.

\(1 \le i\)

c

real

\(r=1\)

Regularization parameter. Controls the trade-off between maximizing the margin between classes and minimizing classification errors. A larger value means higher penalty to the loss function on misclassified observations. Applies to SVC, SVR and NuSVR.

\(0 < r\)

max_iter

integer

\(i=100000\)

Sets the maximum number of iterations. Use 0 to specify no limit.

\(0 \le i\)

nu

real

\(r=0.5\)

An upper bound on the fraction of margin errors and a lower bound of the fraction of support vectors. Applies to NuSVC and NuSVR.

\(0 < r \le 1\)

coef0

real

\(r=0\)

Constant in ‘polynomial’ and ‘sigmoid’ kernels.

There are no constraints on \(r\).

tolerance

real

\(r=10^{-3}\)

Convergence tolerance.

\(0 < r\)

seed

integer

\(i=0\)

Seed for random number generation; set to -1 for non-deterministic results.

\(-1 \le i\)

epsilon

real

\(r=0.1\)

Defines the tolerance for errors in predictions by creating an acceptable margin (tube) within which errors are not penalized. Applies to SVR

\(0 \le r\)

max_ws_size

integer

\(i=-1\)

Specifies the maximum working set size. A value divisible by 64 is recommended for optimal performance. Setting -1 automatically selects the optimal size based on the input data.

\(-1 \le i\)

predict probabilities

integer

\(i=0\)

Evaluate class probabilities (in addition to class predictions).Needs to be 1 if calls to predict_proba or predict_log_probaare made after fit.

\(0 \le i \le 1\)

gamma

real

\(r=-1\)

Parameter for ‘rbf’, ‘polynomial’, and ‘sigmoid’ kernels. If the value is less than 0, it is set to 1/(n_features * Var(X)).

\(-1 \le r\)