<div dir="ltr">In case Nicolas' answer wasn't detailed enough I would use the SAGA invert data/no-data with the no-data value set to 1 on your raster A layer. This will create a mask with 1 in all the cells that were no-data and no-data in all the other cells. Then using the raster calculator run Mask Layer * Layer B = only cells that were no-data in Layer A. <br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Sun, Oct 3, 2021 at 12:50 PM Nicolas Cadieux <<a href="mailto:njacadieux.gitlab@gmail.com">njacadieux.gitlab@gmail.com</a>> wrote:<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">Hi,<div>I would create a mask with raster A where any value = 1 and nodata = 0. Then multiply the raster B by the mask. Anything that comes back as zero contains no data in raster A. <br><br><div dir="ltr">Nicolas Cadieux<div><a href="https://gitlab.com/njacadieux" target="_blank">https://gitlab.com/njacadieux</a></div></div><div dir="ltr"><br><blockquote type="cite">Le 3 oct. 2021 à 10:36, Davide Di Mauro <<a href="mailto:davide.dimauro@alluvium.com.au" target="_blank">davide.dimauro@alluvium.com.au</a>> a écrit :<br><br></blockquote></div><blockquote type="cite"><div dir="ltr">
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<p class="MsoNormal">Hi all,<u></u><u></u></p>
<p class="MsoNormal">I have two rasters.<u></u><u></u></p>
<p class="MsoNormal">I need to output cells of one raster that are not present in the other. How would I go in order to achieve that using the raster calculator (i.e. avoiding Python)?<u></u><u></u></p>
<p class="MsoNormal">My logic so far is:<u></u><u></u></p>
<p class="MsoNormal">if A - B = A then output cells from A deriving from that evaluation and NoData everywhere else.<u></u><u></u></p>
<p class="MsoNormal">The problem is that in the raster calculator I can only evaluate the subtraction and the equality does not evaluate in the same way of the subtraction, even if computed in a different instance.<u></u><u></u></p>
<p class="MsoNormal">Is there a secret ingredient? Can my logic be rewritten differently? or am I way off?<u></u><u></u></p>
<p class="MsoNormal"><u></u> <u></u></p>
<p class="MsoNormal">Cheers<u></u><u></u></p>
<p class="MsoNormal">Davide<u></u><u></u></p>
<p class="MsoNormal"><u></u> <u></u></p>
<p class="MsoNormal"><b><span style="font-size:8pt;color:rgb(64,64,64)">Davide Di Mauro</span></b><b><span style="font-size:8pt;color:rgb(166,166,166)"> |
</span></b><b><span style="font-size:8pt;color:rgb(194,229,112)">Alluvium Consulting Australia<u></u><u></u></span></b></p>
<p class="MsoNormal"><b><span style="font-size:8pt;color:rgb(64,64,64)">GIS Specialist & Flood Modeller</span></b><b><span style="font-size:8pt;color:rgb(194,229,112)"><u></u><u></u></span></b></p>
<p class="MsoNormal"><b><span style="font-size:8pt;color:rgb(194,229,112)">M</span></b><span style="font-size:8pt;color:black"> 0422 634 107</span><span style="font-size:8pt;color:rgb(64,64,64)"><u></u><u></u></span></p>
<p class="MsoNormal"><b><span style="font-size:8pt;color:rgb(194,229,112)">E</span></b><span style="font-size:8pt;color:rgb(194,229,112)"> </span><span style="font-size:8pt;color:black">
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<p class="MsoNormal"><span style="font-size:8pt;color:rgb(64,64,64)"><br>
<b></b></span></p><div><b><image001.jpg></b></div><span><u></u><u></u></span><p></p>
<p class="MsoNormal"><u></u> <u></u></p>
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