<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body style="overflow-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;">If I remember correctly I once did this using genarr<div>I just only used the first few records. </div><div>This is a bit wasteful, but an option. </div><div><br></div><div>Matt</div><div><div><br><blockquote type="cite"><div>On Feb 17, 2023, at 9:42 AM, Patrick Heimbach <heimbach@MIT.EDU> wrote:</div><br class="Apple-interchange-newline"><div><meta charset="UTF-8"><div class="WordSection1" style="page: WordSection1; caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><div style="margin: 0in; font-size: 11pt; font-family: Calibri, sans-serif;"><span style="font-size: 12pt;">Dan,<o:p></o:p></span></div><div style="margin: 0in; font-size: 11pt; font-family: Calibri, sans-serif;"><span style="font-size: 12pt;"><o:p> </o:p></span></div><div style="margin: 0in; font-size: 11pt; font-family: Calibri, sans-serif;"><span style="font-size: 12pt;">Should not be a problem and has been done way back.<o:p></o:p></span></div><div style="margin: 0in; font-size: 11pt; font-family: Calibri, sans-serif;"><span style="font-size: 12pt;"><o:p> </o:p></span></div><div style="margin: 0in; font-size: 11pt; font-family: Calibri, sans-serif;"><span style="font-size: 12pt;">Main thing is to make sure you specify corresponding control variable both in the code and in the argument list of the AD tool. Probably easiest is to add that variable in ctrl.h.<o:p></o:p></span></div><div style="margin: 0in; font-size: 11pt; font-family: Calibri, sans-serif;"><span style="font-size: 12pt;">And then of course also have somewhere to write the adjoint variable. Bottom line, don’t use the gentim, genarr array as controls.<o:p></o:p></span></div><div style="margin: 0in; font-size: 11pt; font-family: Calibri, sans-serif;"><span style="font-size: 12pt;"><o:p> </o:p></span></div><div style="margin: 0in; font-size: 11pt; font-family: Calibri, sans-serif;"><span style="font-size: 12pt;">Remember how we bypassed writing control variables to file initially when getting OpenAD to work. Very much the same steps (but easier) apply here.<o:p></o:p></span></div><div style="margin: 0in; font-size: 11pt; font-family: Calibri, sans-serif;"><span style="font-size: 12pt;"><o:p> </o:p></span></div><div style="margin: 0in; font-size: 11pt; font-family: Calibri, sans-serif;"><span style="font-size: 12pt;">p.<o:p></o:p></span></div><div style="margin: 0in; font-size: 11pt; font-family: Calibri, sans-serif;"><span style="font-size: 12pt;"><o:p> </o:p></span></div><div style="border-style: solid none none; border-top-width: 1pt; border-top-color: rgb(181, 196, 223); padding: 3pt 0in 0in;"><p class="MsoNormal" style="margin: 0in 0in 12pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;"><b><span style="font-size: 12pt;">From:<span class="Apple-converted-space"> </span></span></b><span style="font-size: 12pt;">MITgcm-support <<a href="mailto:mitgcm-support-bounces@mitgcm.org" style="color: blue; text-decoration: underline;">mitgcm-support-bounces@mitgcm.org</a>> on behalf of Daniel Goldberg <<a href="mailto:Dan.Goldberg@ed.ac.uk" style="color: blue; text-decoration: underline;">Dan.Goldberg@ed.ac.uk</a>><br><b>Date:<span class="Apple-converted-space"> </span></b>Friday, February 17, 2023 at 11:30 AM<br><b>To:<span class="Apple-converted-space"> </span></b>MITgcm Support <<a href="mailto:mitgcm-support@mitgcm.org" style="color: blue; text-decoration: underline;">mitgcm-support@mitgcm.org</a>><br><b>Subject:<span class="Apple-converted-space"> </span></b>[MITgcm-support] using (zero-d) scalars as controls with state estimate/optimisation<o:p></o:p></span></p></div><div><div style="margin: 0in 0in 0in 0.5in; font-size: 11pt; font-family: Calibri, sans-serif; background-color: white;"><span style="font-size: 12pt;">Hello All<o:p></o:p></span></div></div><div><div style="margin: 0in 0in 0in 0.5in; font-size: 11pt; font-family: Calibri, sans-serif; background-color: white;"><span style="font-size: 12pt;"><o:p> </o:p></span></div></div><div><div style="margin: 0in 0in 0in 0.5in; font-size: 11pt; font-family: Calibri, sans-serif; background-color: white;"><span style="font-size: 12pt;">As in the subject, I am wondering if any MITgcm/adjoint users have ever used a (zero-dimensional) scalar (either static, or time dependent) as a control, and have any examples of doing so or any advice as to whether it is a good idea. As far as I know, it is only possible to use 2D and 3D static and time varying fields.<o:p></o:p></span></div></div><div><div style="margin: 0in 0in 0in 0.5in; font-size: 11pt; font-family: Calibri, sans-serif; background-color: white;"><span style="font-size: 12pt;"><o:p> </o:p></span></div></div><div><div style="margin: 0in 0in 0in 0.5in; font-size: 11pt; font-family: Calibri, sans-serif; background-color: white;"><span style="font-size: 12pt;">I know that it is possible to ensure that gradients of a genarr2d or gentim2d control are spatially constant e.g. by using a global sum of the control array and adding to a scalar -- but this does not reduce the size of the gradient passed to lsopt or m1qn3, so im not sure if the results would be similar to a case where we simply consider the gradient of a scalar. So Im not sure if this is a suitable replacement. Apologies if what Im saying is unclear.<o:p></o:p></span></div></div><div><div style="margin: 0in 0in 0in 0.5in; font-size: 11pt; font-family: Calibri, sans-serif; background-color: white;"><span style="font-size: 12pt;"><o:p> </o:p></span></div></div><div><div style="margin: 0in 0in 0in 0.5in; font-size: 11pt; font-family: Calibri, sans-serif; background-color: white;"><span style="font-size: 12pt;">Many thanks<o:p></o:p></span></div></div><div><div style="margin: 0in 0in 0in 0.5in; font-size: 11pt; font-family: Calibri, sans-serif; background-color: white;"><span style="font-size: 12pt;">Dan<o:p></o:p></span></div></div><div><div><div style="margin: 0in 0in 0in 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;"><span style="font-size: 12pt;"><o:p> </o:p></span></div></div><div id="Signature"><div><div style="margin: 0in 0in 0in 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;"><span style="font-size: 12pt; font-family: Arial, sans-serif; color: rgb(34, 34, 34); background-color: white;">--</span><o:p></o:p></div><div><div><div><div><div style="margin: 0in 0in 0in 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;"><span style="font-size: 9.5pt; font-family: Arial, sans-serif; color: rgb(34, 34, 34);">Daniel Goldberg, PhD (he/him)</span><span style="font-size: 12pt; font-family: Arial, sans-serif; color: rgb(34, 34, 34);"><o:p></o:p></span></div></div><div><div style="margin: 0in 0in 0in 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;"><span style="font-size: 9.5pt; font-family: Arial, sans-serif; color: rgb(34, 34, 34);">Reader in Glaciology</span><span style="font-size: 12pt; font-family: Arial, sans-serif; color: rgb(34, 34, 34);"><o:p></o:p></span></div><div><div style="margin: 0in 0in 0in 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;"><span style="font-size: 9.5pt; font-family: Arial, sans-serif; color: rgb(34, 34, 34);">School of Geosciences, University of Edinburgh<br></span><span style="font-size: 9.5pt; font-family: Arial, sans-serif;">Geography Building, Drummond Street, Edinburgh EH8 9XP</span><span style="font-size: 9.5pt; font-family: Arial, sans-serif; color: rgb(34, 34, 34);"><br><br><br>em: <a href="mailto:dan.goldberg@ed.ac.uk" target="_blank" style="color: blue; text-decoration: underline;"><span style="color: rgb(17, 85, 204);">dan.goldberg@ed.ac.uk</span></a><br>web: <a href="https://urldefense.com/v3/__https://www.geos.ed.ac.uk/homes/dgoldber__;!!Mih3wA!EGxZ86OBYCNtL6yyR4cNDPGTG5FICOeWgmBvGtvHnGGjKdMToSCEjmoB-1ziqdqmltaVzxT4YZsu_0q4ZkI$" target="_blank" style="color: blue; text-decoration: underline;"><span style="color: rgb(17, 85, 204);">https://www.geos.ed.ac.uk/homes/dgoldber</span></a><o:p></o:p></span></div></div></div></div></div></div></div></div></div><div style="margin: 0in 0in 0in 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;">The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336. Is e buidheann carthannais a th’ ann an Oilthigh Dhùn Èideann, clàraichte an Alba, àireamh clàraidh SC005336.<o:p></o:p></div></div><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;">_______________________________________________</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;">MITgcm-support mailing list</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><a href="mailto:MITgcm-support@mitgcm.org" style="color: blue; text-decoration: underline; font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: 400; 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;">MITgcm-support@mitgcm.org</a><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><a href="https://urldefense.com/v3/__http://mailman.mitgcm.org/mailman/listinfo/mitgcm-support__;!!Mih3wA!EGxZ86OBYCNtL6yyR4cNDPGTG5FICOeWgmBvGtvHnGGjKdMToSCEjmoB-1ziqdqmltaVzxT4YZsul5YFsw0$" style="color: blue; text-decoration: underline; font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: 400; 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;">https://urldefense.com/v3/__http://mailman.mitgcm.org/mailman/listinfo/mitgcm-support__;!!Mih3wA!EGxZ86OBYCNtL6yyR4cNDPGTG5FICOeWgmBvGtvHnGGjKdMToSCEjmoB-1ziqdqmltaVzxT4YZsul5YFsw0$</a><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;"></span></div></blockquote></div><br></div></body></html>