Generates some multibeam data

Generate.py

# coding: utf-8
import math
import sqlite3

from matplotlib import pylab as pl

conn = sqlite3.connect('data.db')

c = conn.cursor()
c.execute('DROP TABLE BEAMS')
# Create table
c.execute('''CREATE TABLE IF NOT EXISTS beams
             (x real, y real, z real, deflection real, visited real, cluster real)''')

beams = 30
sonarWidth = 140 #degrees
roll = 5

beamwidth = float(sonarWidth)/float(beams)

depth = 10
x = []
y = []
z = []

linePings = 100

for trackOffsetStep in range(3):
    for alongTrackStep in range(linePings):
        roll = 5*math.cos( (alongTrackStep + linePings*trackOffsetStep) * 5 / 180.0 * math.pi )
        for i in range(beams):
            angle = i*beamwidth - sonarWidth/2.0 + beamwidth/2.0 + roll
            y.append( depth*math.tan(angle/180*math.pi) + trackOffsetStep * 50 )
            z.append( depth )
            x.append( alongTrackStep )
        
            # Insert a row of data
            c.execute("INSERT INTO beams VALUES (?,?,?,?,0,0)",(x[-1],y[-1],z[-1],angle) )
        

#https://en.m.wikipedia.org/wiki/DBSCAN



# Save (commit) the changes
conn.commit()

# We can also close the connection if we are done with it.
# Just be sure any changes have been committed or they will be lost.
conn.close()

pl.plot(x,y,'.')
pl.show()