Set point geometry of a list of points in PYQGIS

Question

I want to create a temporary point layer from a list of points. The point list is:

arr_error = [[547162.6286000004, 187063.95659999922]]

vl = QgsVectorLayer('Point', 'Error_point', 'memory')
    pr = vl.dataProvider()
    pr.addAttributes([QgsField("Name", QVariant.String)])
    vl.updateFields()
    for x in arr_error:
        
        fet = QgsFeature()
        pt = QgsPointXY(x[0],x[1])
        
        fet.setGeometry(QgsGeometry.fromPointXY(pt))
        fet.setAttributes(['Error'])
        pr.addFeatures([fet])
    vl.updateExtents()
    QgsProject.instance().addMapLayers([vl])

This creates a layer, feature is added to layer. But geometry is not being set. What mistake i am doing in the code??

Answer 1

You need to define a Coordinate Reference System for your layer. You can do this when you define your QgsVectorLayer object like this:

vl = QgsVectorLayer('Point?crs=EPSG:3857', 'Error_point', 'memory')

Or subsequently like this:

vl = QgsVectorLayer('Point', 'Error_point', 'memory')
vl.setCrs(QgsCoordinateReferenceSystem('EPSG:3857'))

Note: I just used EPSG:3857 for this example, to show the syntax. Of course, you should use whatever CRS your point coordinates are actually in.