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<p>Hi,</p>
<p>I get the expected 4070327.25 166078.93 4891298.61 result with
proj 6.0.0, 7.2.1, 9.2.0 and master</p>
<p>There's no grid involved in this operation, just inverse LCC
projection on the RGF93 datum</p>
<p>I also tried to reproduce your issue if the PROJ < 6 IGNF file
is found in the PROJ resource path(s) (non nominal situation -
this file is not needed any more, and will generally lead to
suboptimal results. Its content is included in the proj.db file),
but even with that I get the expected result. So no idea why you
get wrong results<br>
</p>
<p>Even</p>
<p><br>
</p>
<div class="moz-cite-prefix">Le 26/05/2023 à 20:54, Nicolas
Bellaiche a écrit :<br>
</div>
<blockquote type="cite"
cite="mid:1554747504.7324762.1685127274306.JavaMail.zimbra@ign.fr">
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<div style="font-family: arial, helvetica, sans-serif; font-size:
12pt; color: #000000">
<div>Hi all,</div>
<div><br data-mce-bogus="1">
</div>
<div>I'm migrating my C++ code from PROJ4 to PROJ9 and I meet a
worrying issue with the computation. Some of my regress tests
don't pass so I've tested with cs2cs and gets the same
difference:</div>
<div><br data-mce-bogus="1">
</div>
<div>
<p style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);
font-style: normal; font-variant-caps: normal; font-weight:
normal; letter-spacing: normal; orphans: auto; text-align:
start; text-indent: 0px; text-transform: none; white-space:
normal; widows: auto; word-spacing: 0px;
-webkit-text-size-adjust: auto; -webkit-text-stroke-width:
0px; text-decoration: none; margin: 0px; font-stretch:
normal; font-size: 11px; line-height: normal; font-family:
menlo;" data-mce-style="caret-color: #000000; color:
#000000; font-style: normal; font-variant-caps: normal;
font-weight: normal; letter-spacing: normal; orphans: auto;
text-align: start; text-indent: 0px; text-transform: none;
white-space: normal; widows: auto; word-spacing: 0px;
-webkit-text-size-adjust: auto; -webkit-text-stroke-width:
0px; text-decoration: none; margin: 0px; font-stretch:
normal; font-size: 11px; line-height: normal; font-family:
menlo;"><span class="Apple-converted-space">PROJ4</span></p>
<p style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);
font-style: normal; font-variant-caps: normal; font-weight:
normal; letter-spacing: normal; orphans: auto; text-align:
start; text-indent: 0px; text-transform: none; white-space:
normal; widows: auto; word-spacing: 0px;
-webkit-text-size-adjust: auto; -webkit-text-stroke-width:
0px; text-decoration: none; margin: 0px; font-stretch:
normal; font-size: 11px; line-height: normal; font-family:
menlo;" data-mce-style="caret-color: #000000; color:
#000000; font-style: normal; font-variant-caps: normal;
font-weight: normal; letter-spacing: normal; orphans: auto;
text-align: start; text-indent: 0px; text-transform: none;
white-space: normal; widows: auto; word-spacing: 0px;
-webkit-text-size-adjust: auto; -webkit-text-stroke-width:
0px; text-decoration: none; margin: 0px; font-stretch:
normal; font-size: 11px; line-height: normal; font-family:
menlo;"><span class="Apple-converted-space"> </span>echo<span
class="Apple-converted-space"> </span><span class="Object"
role="link" id="OBJ_PREFIX_DWT157_com_zimbra_phone"
style="color: #005a95; text-decoration: none; cursor:
pointer;" data-mce-style="color: #005a95; text-decoration:
none; cursor: pointer;"><a href="callto:652760.73700000"
style="color: #005a95; text-decoration: none; cursor:
pointer;" data-mce-href="callto:652760.73700000"
data-mce-style="color: #005a95; text-decoration: none;
cursor: pointer;" moz-do-not-send="true">652760.73700000</a></span><span
class="Apple-converted-space"> </span><span class="Object"
role="link" id="OBJ_PREFIX_DWT158_com_zimbra_phone"
style="color: #005a95; text-decoration: none; cursor:
pointer;" data-mce-style="color: #005a95; text-decoration:
none; cursor: pointer;"><a href="callto:7033791.24300000
43" style="color: #005a95; text-decoration: none;
cursor: pointer;" data-mce-href="callto:7033791.24300000
43" data-mce-style="color: #005a95; text-decoration:
none; cursor: pointer;" moz-do-not-send="true">7033791.24300000
43</a></span>.64200000 | cs2cs +init=IGNF:LAMB93 +to
+init=IGNF:RGF93: </p>
<p style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);
font-style: normal; font-variant-caps: normal; font-weight:
normal; letter-spacing: normal; orphans: auto; text-align:
start; text-indent: 0px; text-transform: none; white-space:
normal; widows: auto; word-spacing: 0px;
-webkit-text-size-adjust: auto; -webkit-text-stroke-width:
0px; text-decoration: none; margin: 0px; font-stretch:
normal; font-size: 11px; line-height: normal; font-family:
menlo;" data-mce-style="caret-color: #000000; color:
#000000; font-style: normal; font-variant-caps: normal;
font-weight: normal; letter-spacing: normal; orphans: auto;
text-align: start; text-indent: 0px; text-transform: none;
white-space: normal; widows: auto; word-spacing: 0px;
-webkit-text-size-adjust: auto; -webkit-text-stroke-width:
0px; text-decoration: none; margin: 0px; font-stretch:
normal; font-size: 11px; line-height: normal; font-family:
menlo;">4070327.25<span class="Apple-tab-span" style="white-space: pre;" data-mce-style="white-space: pre;"> </span><span
class="Object" role="link"
id="OBJ_PREFIX_DWT159_com_zimbra_phone" style="color:
#005a95; text-decoration: none; cursor: pointer;"
data-mce-style="color: #005a95; text-decoration: none;
cursor: pointer;"><a href="callto:166078.93 4891298.61"
style="color: #005a95; text-decoration: none; cursor:
pointer;" data-mce-href="callto:166078.93 4891298.61"
data-mce-style="color: #005a95; text-decoration: none;
cursor: pointer;" moz-do-not-send="true">166078.93
4891298.61</a></span></p>
<p style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);
font-style: normal; font-variant-caps: normal; font-weight:
normal; letter-spacing: normal; orphans: auto; text-align:
start; text-indent: 0px; text-transform: none; white-space:
normal; widows: auto; word-spacing: 0px;
-webkit-text-size-adjust: auto; -webkit-text-stroke-width:
0px; text-decoration: none; margin: 0px; font-stretch:
normal; font-size: 11px; line-height: normal; font-family:
menlo; min-height: 13px;" data-mce-style="caret-color:
#000000; color: #000000; font-style: normal;
font-variant-caps: normal; font-weight: normal;
letter-spacing: normal; orphans: auto; text-align: start;
text-indent: 0px; text-transform: none; white-space: normal;
widows: auto; word-spacing: 0px; -webkit-text-size-adjust:
auto; -webkit-text-stroke-width: 0px; text-decoration: none;
margin: 0px; font-stretch: normal; font-size: 11px;
line-height: normal; font-family: menlo; min-height: 13px;"><br>
</p>
<p style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);
font-style: normal; font-variant-caps: normal; font-weight:
normal; letter-spacing: normal; orphans: auto; text-align:
start; text-indent: 0px; text-transform: none; white-space:
normal; widows: auto; word-spacing: 0px;
-webkit-text-size-adjust: auto; -webkit-text-stroke-width:
0px; text-decoration: none; margin: 0px; font-stretch:
normal; font-size: 11px; line-height: normal; font-family:
menlo; min-height: 13px;" data-mce-style="caret-color:
#000000; color: #000000; font-style: normal;
font-variant-caps: normal; font-weight: normal;
letter-spacing: normal; orphans: auto; text-align: start;
text-indent: 0px; text-transform: none; white-space: normal;
widows: auto; word-spacing: 0px; -webkit-text-size-adjust:
auto; -webkit-text-stroke-width: 0px; text-decoration: none;
margin: 0px; font-stretch: normal; font-size: 11px;
line-height: normal; font-family: menlo; min-height: 13px;">PROJ7
or PROJ9</p>
<p style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);
font-style: normal; font-variant-caps: normal; font-weight:
normal; letter-spacing: normal; orphans: auto; text-align:
start; text-indent: 0px; text-transform: none; white-space:
normal; widows: auto; word-spacing: 0px;
-webkit-text-size-adjust: auto; -webkit-text-stroke-width:
0px; text-decoration: none; margin: 0px; font-stretch:
normal; font-size: 11px; line-height: normal; font-family:
menlo;" data-mce-style="caret-color: #000000; color:
#000000; font-style: normal; font-variant-caps: normal;
font-weight: normal; letter-spacing: normal; orphans: auto;
text-align: start; text-indent: 0px; text-transform: none;
white-space: normal; widows: auto; word-spacing: 0px;
-webkit-text-size-adjust: auto; -webkit-text-stroke-width:
0px; text-decoration: none; margin: 0px; font-stretch:
normal; font-size: 11px; line-height: normal; font-family:
menlo;"><span class="Apple-converted-space"> </span>echo<span
class="Apple-converted-space"> </span><span class="Object"
role="link" id="OBJ_PREFIX_DWT160_com_zimbra_phone"
style="color: #005a95; text-decoration: none; cursor:
pointer;" data-mce-style="color: #005a95; text-decoration:
none; cursor: pointer;"><a href="callto:652760.73700000"
style="color: #005a95; text-decoration: none; cursor:
pointer;" data-mce-href="callto:652760.73700000"
data-mce-style="color: #005a95; text-decoration: none;
cursor: pointer;" moz-do-not-send="true">652760.73700000</a></span><span
class="Apple-converted-space"> </span><span class="Object"
role="link" id="OBJ_PREFIX_DWT161_com_zimbra_phone"
style="color: #005a95; text-decoration: none; cursor:
pointer;" data-mce-style="color: #005a95; text-decoration:
none; cursor: pointer;"><a href="callto:7033791.24300000
43" style="color: #005a95; text-decoration: none;
cursor: pointer;" data-mce-href="callto:7033791.24300000
43" data-mce-style="color: #005a95; text-decoration:
none; cursor: pointer;" moz-do-not-send="true">7033791.24300000
43</a></span>.64200000 | cs2cs +init=IGNF:LAMB93 +to
+init=IGNF:RGF93:<span class="Apple-converted-space"> </span></p>
<p style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);
font-style: normal; font-variant-caps: normal; font-weight:
normal; letter-spacing: normal; orphans: auto; text-align:
start; text-indent: 0px; text-transform: none; white-space:
normal; widows: auto; word-spacing: 0px;
-webkit-text-size-adjust: auto; -webkit-text-stroke-width:
0px; text-decoration: none; margin: 0px; font-stretch:
normal; font-size: 11px; line-height: normal; font-family:
menlo;" data-mce-style="caret-color: #000000; color:
#000000; font-style: normal; font-variant-caps: normal;
font-weight: normal; letter-spacing: normal; orphans: auto;
text-align: start; text-indent: 0px; text-transform: none;
white-space: normal; widows: auto; word-spacing: 0px;
-webkit-text-size-adjust: auto; -webkit-text-stroke-width:
0px; text-decoration: none; margin: 0px; font-stretch:
normal; font-size: 11px; line-height: normal; font-family:
menlo;">4070355.05<span class="Apple-tab-span" style="white-space: pre;" data-mce-style="white-space: pre;"> </span><span
class="Object" role="link"
id="OBJ_PREFIX_DWT162_com_zimbra_phone" style="color:
#005a95; text-decoration: none; cursor: pointer;"
data-mce-style="color: #005a95; text-decoration: none;
cursor: pointer;"><a href="callto:166080.07 4891332.24"
style="color: #005a95; text-decoration: none; cursor:
pointer;" data-mce-href="callto:166080.07 4891332.24"
data-mce-style="color: #005a95; text-decoration: none;
cursor: pointer;" moz-do-not-send="true">166080.07
4891332.24</a></span></p>
<p style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);
font-style: normal; font-variant-caps: normal; font-weight:
normal; letter-spacing: normal; orphans: auto; text-align:
start; text-indent: 0px; text-transform: none; white-space:
normal; widows: auto; word-spacing: 0px;
-webkit-text-size-adjust: auto; -webkit-text-stroke-width:
0px; text-decoration: none; margin: 0px; font-stretch:
normal; font-size: 11px; line-height: normal; font-family:
menlo;" data-mce-style="caret-color: #000000; color:
#000000; font-style: normal; font-variant-caps: normal;
font-weight: normal; letter-spacing: normal; orphans: auto;
text-align: start; text-indent: 0px; text-transform: none;
white-space: normal; widows: auto; word-spacing: 0px;
-webkit-text-size-adjust: auto; -webkit-text-stroke-width:
0px; text-decoration: none; margin: 0px; font-stretch:
normal; font-size: 11px; line-height: normal; font-family:
menlo;"><span class="Object" role="link" style="color:
#005a95; text-decoration: none; cursor: pointer;"
data-mce-style="color: #005a95; text-decoration: none;
cursor: pointer;"><br data-mce-bogus="1">
</span></p>
<p style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);
font-style: normal; font-variant-caps: normal; font-weight:
normal; letter-spacing: normal; orphans: auto; text-align:
start; text-indent: 0px; text-transform: none; white-space:
normal; widows: auto; word-spacing: 0px;
-webkit-text-size-adjust: auto; -webkit-text-stroke-width:
0px; text-decoration: none; margin: 0px; font-stretch:
normal; font-size: 11px; line-height: normal; font-family:
menlo;" data-mce-style="caret-color: #000000; color:
#000000; font-style: normal; font-variant-caps: normal;
font-weight: normal; letter-spacing: normal; orphans: auto;
text-align: start; text-indent: 0px; text-transform: none;
white-space: normal; widows: auto; word-spacing: 0px;
-webkit-text-size-adjust: auto; -webkit-text-stroke-width:
0px; text-decoration: none; margin: 0px; font-stretch:
normal; font-size: 11px; line-height: normal; font-family:
menlo;"><span class="Object" role="link" style="color:
#005a95; text-decoration: none; cursor: pointer;"
data-mce-style="color: #005a95; text-decoration: none;
cursor: pointer;"><br data-mce-bogus="1">
</span></p>
</div>
<div><br data-mce-bogus="1">
</div>
<div>I suspect that PROJ7 and PROJ9 don't read properly the
geoid file but I'm not sure. Someone can help me tracking and
fixing this problem?</div>
<div><br>
Thanks,</div>
<div><br data-mce-bogus="1">
</div>
<div>Nicolas Bellaiche</div>
<div>Institut Géographique National France</div>
</div>
<br>
<fieldset class="moz-mime-attachment-header"></fieldset>
<pre class="moz-quote-pre" wrap="">_______________________________________________
PROJ mailing list
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</pre>
</blockquote>
<pre class="moz-signature" cols="72">--
<a class="moz-txt-link-freetext" href="http://www.spatialys.com">http://www.spatialys.com</a>
My software is free, but my time generally not.</pre>
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