Hi everyone, 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,
line start_time end_time series (I generated this as a count of the seconds difference between the above time fields. I thought it would be useful) So for example my table (temp4) might look like this: line || start_time || end_time || series ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ line_geom || 12:07:17 || 12:07:20 || 3 line_geom || 12:07:17 || 12:07:20 || 2 line_geom || 12:07:17 || 12:07:20 || 1 line_geom || 12:07:21 || 12:07:26 || 6 line_geom || 12:07:21 || 12:07:26 || 5 line_geom || 12:07:21 || 12:07:26 || 4 line_geom || 12:07:21 || 12:07:26 || 3 line_geom || 12:07:21 || 12:07:26 || 2 line_geom || 12:07:21 || 12:07:26 || 1 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. So I've been trying something like this, but it's wrong. But maybe along the right lines. SELECT st_line_interpolate_point(line, 1/series::float)) as new_point FROM temp4 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. line || start_time || end_time || series || percentage along line ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ line_geom || 12:07:17 || 12:07:20 || 3 || 0.33% line_geom || 12:07:17 || 12:07:20 || 2 || 0.67 line_geom || 12:07:17 || 12:07:20 || 1 || 100% Sorry for the long explanation. Hope that you understand where I am coming from. Grateful for any ideas please! Thanks James
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