Algorithm 1: DBSCAN algorithm pseudo-code

Input: Sample set $\mathit{D}=\left\{{\mathit{x}}_{\mathbf{1}},{\mathit{x}}_{\mathbf{2}},\cdots \cdots ,{\mathit{x}}_{\mathit{m}}\right\}$, neighborhood parameters $\left(\mathit{E}\mathit{p}\mathit{s},\mathit{M}\mathit{i}\mathit{n}\mathit{p}\mathit{t}\mathit{s}\right)$

Workflow:

Initializing the core object set: $\Omega =\varnothing$;

forj = 1, 2……, m

Determine the number of samples ${\mathit{N}}_{\mathit{E}\mathit{p}\mathit{s}}\left({\mathit{x}}_{\mathit{j}}\right)$ in the $\mathit{E}\mathit{p}\mathit{s}$-neighborhood of sample ${\mathit{x}}_{\mathit{j}}$;

if ${\mathit{N}}_{\mathit{E}\mathit{p}\mathit{s}}\left({\mathit{x}}_{\mathit{j}}\right)\ge \mathit{M}\mathit{i}\mathit{n}\mathit{p}\mathit{t}\mathit{s}$

Put sample ${\mathit{x}}_{\mathit{j}}$ into the core sample set: $\mathbf{\Omega }=\Omega \cup \left\{{\mathit{x}}_{\mathit{j}}\right\}$;

end if

end for

Initialize the number of clusters: $\mathit{k}=\mathbf{0}$;

Initialize the set of unaccessed samples: $\mathit{\Gamma }=\mathit{D}$;

while$\Omega \ne \varnothing$

Sample sets not currently being accessed:${\mathit{\Gamma }}_{\mathit{o}\mathit{l}\mathit{d}}=\mathit{\Gamma }$;

Randomly select core objects $\mathit{c}\in \Omega$, initializing the queue $\mathit{Q}=\langle \mathit{c}\rangle$;

Γ = Γ$\backslash \left\{\mathit{c}\right\}$;

While $\mathit{Q}\ne \varnothing$

Take the first sample q from the queue Q

if ${\mathit{N}}_{\mathit{E}\mathit{p}\mathit{s}}\left(x_j\right)\ge \mathit{M}\mathit{i}\mathit{n}\mathit{p}\mathit{t}\mathit{s}$

Make $\Delta ={\mathit{N}}_{\mathit{E}\mathit{p}\mathit{s}}\left(\mathit{q}\right)\cap \mathit{\Gamma }$,

Put all elements of $\Delta$ into the queue Q;

Γ = Γ \$\Delta$;

end if

end while

k = k + 1, generate clusters ${\mathit{C}}_{\mathit{k}}={\mathit{\Gamma }}_{\mathit{o}\mathit{l}\mathit{d}} \backslash \mathit{\Gamma }$;

$\Omega =\Omega \backslash {\mathit{C}}_{\mathit{k}}$ end while Output: cluster classification $\mathit{C}=\left\{{\mathit{C}}_{\mathbf{1}},{\mathit{C}}_{\mathbf{2}},\cdots ,{\mathit{C}}_{\mathit{k}}\right\}$;