<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body 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">https://gitlab.com/njacadieux</a></div></div><div dir="ltr"><br><blockquote type="cite">Le 3 oct. 2021 à 10:36, Davide Di Mauro <davide.dimauro@alluvium.com.au> a écrit :<br><br></blockquote></div><blockquote type="cite"><div dir="ltr">
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<p class="MsoNormal">Hi all,<o:p></o:p></p>
<p class="MsoNormal">I have two rasters.<o:p></o:p></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)?<o:p></o:p></p>
<p class="MsoNormal">My logic so far is:<o:p></o:p></p>
<p class="MsoNormal">if A - B = A then output cells from A deriving from that evaluation and NoData everywhere else.<o:p></o:p></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.<o:p></o:p></p>
<p class="MsoNormal">Is there a secret ingredient? Can my logic be rewritten differently? or am I way off?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Cheers<o:p></o:p></p>
<p class="MsoNormal">Davide<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b><span style="font-size:8.0pt;color:#404040;mso-fareast-language:EN-AU">Davide Di Mauro</span></b><b><span style="font-size:8.0pt;color:#A6A6A6;mso-fareast-language:EN-AU"> |
</span></b><b><span style="font-size:8.0pt;color:#C2E570;mso-fareast-language:EN-AU">Alluvium Consulting Australia<o:p></o:p></span></b></p>
<p class="MsoNormal"><b><span style="font-size:8.0pt;color:#404040;mso-fareast-language:EN-AU">GIS Specialist & Flood Modeller</span></b><b><span style="font-size:8.0pt;color:#C2E570;mso-fareast-language:EN-AU"><o:p></o:p></span></b></p>
<p class="MsoNormal"><b><span style="font-size:8.0pt;color:#C2E570;mso-fareast-language:EN-AU">M</span></b><span style="font-size:8.0pt;color:black;mso-fareast-language:EN-AU"> 0422 634 107</span><span style="font-size:8.0pt;color:#404040;mso-fareast-language:EN-AU"><o:p></o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:8.0pt;color:#C2E570;mso-fareast-language:EN-AU">E</span></b><span style="font-size:8.0pt;color:#C2E570;mso-fareast-language:EN-AU"> </span><span style="font-size:8.0pt;color:black;mso-fareast-language:EN-AU">
</span><span style="font-size:8.0pt;color:#3B3838;mso-fareast-language:EN-AU"><a href="mailto:davide.dimauro@alluvium.com.au"><span style="color:#0563C1">davide.dimauro@alluvium.com.au</span></a><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:8.0pt;color:#404040;mso-fareast-language:EN-AU"><a href="http://www.alluvium.com.au/"><span style="color:#404040">www.alluvium.com.au</span></a>
</span><span style="font-size:8.0pt;color:#BFBFBF;mso-fareast-language:EN-AU">|</span><span style="font-size:8.0pt;color:#404040;mso-fareast-language:EN-AU"> Suite 12 - 36 Agnes St, Fortitude Valley - 4006</span><span style="font-size:8.0pt;color:#BFBFBF;mso-fareast-language:EN-AU">|</span><span style="color:#BFBFBF;mso-fareast-language:EN-AU">
</span><span style="font-size:8.0pt;color:#404040;mso-fareast-language:EN-AU"><a href="http://www.linkedin.com/company/alluvium-consulting" target="_blank"><span style="color:#404040">LinkedIn</span></a><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:8.0pt;color:#404040;mso-fareast-language:EN-AU"><br>
<b><div><image001.jpg></div></b></span><span style="mso-fareast-language:EN-AU"><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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