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<div class="">On 15 Jun 2019, at 17:22, Haas, Roland <<a href="mailto:rhaas@illinois.edu" class="">rhaas@illinois.edu</a>> wrote:</div>
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The alternative is to introduce a helper grid function where you<br class="">
manually zero out the regions you do not care about then compute the<br class="">
norm of that grid function.<br class="">
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<div>Perhaps a mask would be of use here?</div>
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-- <br class="">
Ian<b class=""><span class="Apple-converted-space"> </span></b>Hinder<br class="">
Research Software Engineer<br class="">
University of Manchester, UK</div>
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