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<p>Hi list -
</p>
<p>I can't find a method to use a Number input as a part of raster calculator expression in Model Designer.</p>
<p>Using QGIS version 3.42, in Model Designer I've:</p>
<ul>
<li>Defined a Number Input field: <i>my_number</i></li>
<li>Defined a Raster Layer selector : <i>my_raster</i></li>
<li>Defined a Rater Calculator algorithm: <i>multiplication</i></li>
</ul>
<p>Now the crucial question: How to use the number from my number input in an expression inside Raster Calculator?</p>
<p>Ex. for a simple multiplication: <i>"A@1" * parameter('my_number')</i> or <i>"A@1" * @my_number</i> </p>
<p>Whatever I do, I get an error message like this:</p>
<p><span style=" font-weight:600;">Algorithm 'model' starting…</span></p>
<p></p>
<p
style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;">Input parameters:</p>
<p
style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;"><span
style=" font-family:'Courier New';">{ 'my_number' : 22, 'my_raster' : 'D:/gis/gis_analyser/flis_volumen/normaliseret.tif', 'resultat' : 'TEMPORARY_OUTPUT' }</span></p>
<p
style="-qt-paragraph-type:empty; margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;">
</p>
<p
style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;"><span
style=" color:#777777;">Prepare algorithm: native:modelerrastercalc_1</span></p>
<p
style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;">Running multiplication [1/1]</p>
<p
style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;">Input Parameters:</p>
<p
style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;"><span
style=" font-family:'Courier New';">{ CELL_SIZE: None, CREATION_OPTIONS: None, CRS: None, EXPRESSION: '"A@1" * parameter(\'my_number\')', EXTENT: None, LAYERS: ['D:/gis/gis_analyser/flis_volumen/normaliseret.tif'], OUTPUT: 'TEMPORARY_OUTPUT' }</span></p>
<p
style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;"><span
style=" color:#ff0000;">Error encountered while running multiplication: Error parsing formula.</span></p>
<p
style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;"><span
style=" color:#ff0000;">Execution failed after 0.04 seconds</span></p>
<br>
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<p></p>
<style type="text/css">p, li { white-space: pre-wrap; }</style>
<p> The error message indicate an error in my expression: <i>"A@1" * parameter('my_number')</i></p>
So, how do i declare and use a Number Input inside a raster
calculator expression ?? <br>
<p>
</p>
<pre class="moz-signature" cols="72">--
Med venlig hilsen / Best regards
Bo Victor Thomsen</pre>
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