<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>
<body>
<p>Hi Francois<br>
</p>
<div class="moz-cite-prefix">Am 21.03.2021 um 19:15 schrieb François
Lacombe:<br>
</div>
<blockquote type="cite"
cite="mid:CAG0ygLcqx21H+V7ayaDYnnvU6Ov8Xr1Cso11vapo47NP1_sicg@mail.gmail.com">
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<div dir="ltr">
<div>Thank you Darafei</div>
<div><br>
</div>
<div>You link points me to an OverpassAPI endpoint and I don't
get how I'm able to produce augmented diff from an osc file.</div>
</div>
</blockquote>
<p>You can't. <br>
</p>
<p>Essentially you have two choices</p>
<p>- have a database that has all the required current state /
geometries, then you can generate all the geometry changes from
that plus the osc file.</p>
<p>- you use Overpass augmented diffs instead of the osc diff feed
(arguably augmented diffs are overkill for this, but it is what we
have). The augmented diffs contain all the necessary information
plus some to recreated the geometry changes.</p>
<p>Simon<br>
</p>
<p><br>
</p>
<blockquote type="cite"
cite="mid:CAG0ygLcqx21H+V7ayaDYnnvU6Ov8Xr1Cso11vapo47NP1_sicg@mail.gmail.com">
<div dir="ltr">
<div>Osmchange is mentioned as a reader of augmented diff, but
not as a producer.</div>
<div><br>
</div>
<div>Any extra elaboration will be welcome, all the best</div>
<div><br>
</div>
<div>François</div>
</div>
<br>
<div class="gmail_quote">
<div dir="ltr" class="gmail_attr">Le dim. 21 mars 2021 à 18:17,
Darafei "Komяpa" Praliaskouski <<a
href="mailto:me@komzpa.net" moz-do-not-send="true">me@komzpa.net</a>>
a écrit :<br>
</div>
<blockquote class="gmail_quote" style="margin:0px 0px 0px
0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div dir="auto"><a
href="https://wiki.openstreetmap.org/wiki/Overpass_API/Augmented_Diffs"
target="_blank" moz-do-not-send="true">https://wiki.openstreetmap.org/wiki/Overpass_API/Augmented_Diffs</a></div>
<br>
<div class="gmail_quote">
<div dir="ltr" class="gmail_attr">нд, 21 сак 2021, 20:01
карыстальнік François Lacombe <<a
href="mailto:fl.infosreseaux@gmail.com" target="_blank"
moz-do-not-send="true">fl.infosreseaux@gmail.com</a>>
напісаў:<br>
</div>
<blockquote class="gmail_quote" style="margin:0px 0px 0px
0.8ex;border-left:1px solid
rgb(204,204,204);padding-left:1ex">
<div dir="ltr">
<div>Hi all</div>
<div><br>
</div>
<div>For the needs of ProjetDuMois statistics computing
chain, I'm looking for an appropriate logic to get
geometries associated with osm changes in an osc file,
particularly for past versions.</div>
<div><br>
</div>
<div>According to this discussion, it sounds to not be
easy.</div>
<div><a
href="https://help.openstreetmap.org/questions/58931/osc-to-osm-change-file-to-osm-osmium/58948"
rel="noreferrer" target="_blank"
moz-do-not-send="true">https://help.openstreetmap.org/questions/58931/osc-to-osm-change-file-to-osm-osmium/58948</a></div>
<div><br>
</div>
<div>Currently, we convert an OSC file to CSV without
any geometry information</div>
<div><a
href="https://github.com/vdct/ProjetDuMois/blob/master/db/10_project_update.js#L275"
rel="noreferrer" target="_blank"
moz-do-not-send="true">https://github.com/vdct/ProjetDuMois/blob/master/db/10_project_update.js#L275</a></div>
<div>with following xslt sheet</div>
<div><a
href="https://github.com/vdct/ProjetDuMois/blob/master/db/osc2csv.xslt"
rel="noreferrer" target="_blank"
moz-do-not-send="true">https://github.com/vdct/ProjetDuMois/blob/master/db/osc2csv.xslt</a></div>
<div><br>
</div>
<div>We now aim to group and count changes against some
administrative boundaries. As a given feature can
change of admin area between two versions, we must
filter the changes we're interested in, intersect each
of them with selected admin boundaries and finally
count how may they are in each admin boundary.<br>
</div>
<div><br>
</div>
<div>Despite I'll be able to get lat/lon for nodes,
rebuild linestrings for ways will be tricky as we'll
have to not only check against nodes ids but
timestamps as well.<br>
</div>
<div><br>
</div>
<div>It's not a problem to do that each day with daily
updates but issues occurs when we drop the database
and try to get back 2 or 3 month with no geometry
history at all.<br>
</div>
<div>See this chart (in French) : <a
href="https://github.com/vdct/ProjetDuMois/issues/188#issuecomment-802221915"
rel="noreferrer" target="_blank"
moz-do-not-send="true">https://github.com/vdct/ProjetDuMois/issues/188#issuecomment-802221915</a></div>
<div><br>
</div>
<div>I'll be happy to discuss about such process here as
I think someone may already had to solve it.</div>
<div>Thanks in advance, all the best</div>
<div><br>
</div>
<div>François</div>
</div>
_______________________________________________<br>
dev mailing list<br>
<a href="mailto:dev@openstreetmap.org" rel="noreferrer"
target="_blank" moz-do-not-send="true">dev@openstreetmap.org</a><br>
<a href="https://lists.openstreetmap.org/listinfo/dev"
rel="noreferrer noreferrer" target="_blank"
moz-do-not-send="true">https://lists.openstreetmap.org/listinfo/dev</a><br>
</blockquote>
</div>
</blockquote>
</div>
<br>
<fieldset class="mimeAttachmentHeader"></fieldset>
<pre class="moz-quote-pre" wrap="">_______________________________________________
dev mailing list
<a class="moz-txt-link-abbreviated" href="mailto:dev@openstreetmap.org">dev@openstreetmap.org</a>
<a class="moz-txt-link-freetext" href="https://lists.openstreetmap.org/listinfo/dev">https://lists.openstreetmap.org/listinfo/dev</a>
</pre>
</blockquote>
</body>
</html>