QGIS Polygon Fill – Filling Gaps Between Polygons

fillgappolygonpolygon-creationqgis

Here are my polygons of town blocks.

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The colored towns are considered as areas where they have the same post code.

What I eventually want is to make seamless polygons where there are no gaps between polygons (please see the screenshot below)

enter image description here

What functions should I use to complete my mission?

Best Answer

@Pil Kwon, since you have the same "post-code", therefore in QGIS I can suggest using a "Convex Hull":

Vector > Geoprocessing Tools > Convex Hull

Hint: Create Convex Hulls based on a field.

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