<div>Hi everyone,</div><div> </div><div>I'm flirted around this problem for a while, so I hope I'm not bein annoying by being repetative, but I've been tearing my hair out trying to do it. The problem is that I have a file of lines (geometry). in a table called temp4 The format of the table is, simplified,</div>
<div> </div><div>line</div><div>start_time</div><div>end_time</div><div>series (I generated this as a count of the seconds difference between the above time fields. I thought it would be useful)</div><div> </div><div>So for example my table (temp4) might look like this:</div>
<div> </div><div>line || start_time || end_time || series</div><div>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~</div><div>line_geom || 12:07:17 || 12:07:20 || 3</div>
<div>line_geom || 12:07:17 || 12:07:20 || 2</div><div>line_geom || 12:07:17 || 12:07:20 || 1</div><div> </div><div>line_geom || 12:07:21 || 12:07:26 || 6</div>
<div><div>line_geom || 12:07:21 || 12:07:26 || 5</div><div>line_geom || 12:07:21 || 12:07:26 || 4</div><div>line_geom || 12:07:21 || 12:07:26 || 3</div>
<div><div>line_geom || 12:07:21 || 12:07:26 || 2</div><div>line_geom || 12:07:21 || 12:07:26 || 1</div><div> </div></div></div>
<div> </div><div>Now what I want to do is split the lines into points, with a point for each second. Evenly spaced along the line. So if the line is 10 metres long and the difference between the start and end is 10 seconds then I want to create 9 points at 10% along the line, 20% along the line, 30% along the line etc up to a point which is 100% along the line i.e. the end of the line. I don't need a new point at the start of the line as I have that stored already.</div>
<div> </div><div>So I've been trying something like this, but it's wrong. But maybe along the right lines.</div><div> </div><div>SELECT st_line_interpolate_point(line, 1/series::float)) as new_point<br>FROM temp4</div>
<div> </div><div>Taking the first few rows of my data, the percentages along the lines I want to generate are as follows. I need to find a way to get these values into the st_line_interpolate_line function.</div><div> </div>
<div><div>line || start_time || end_time || series || percentage along line</div><div>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~</div>
<div>line_geom || 12:07:17 || 12:07:20 || 3 || 0.33%</div><div>line_geom || 12:07:17 || 12:07:20 || 2 || 0.67 </div>
<div>line_geom || 12:07:17 || 12:07:20 || 1 || 100% </div></div><div> </div><div>Sorry for the long explanation. Hope that you understand where I am coming from. Grateful for any ideas please!</div>
<div> </div><div>Thanks</div><div> </div><div>James</div>