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I am trying to plot polygons in WKT format I have in an array onto a single layer and add it to my map. I can post 1 polygon by referencing an entry in the entry (array[0]) and I have managed to plot many polygons from an array in straightforward coordinate format but I cannot manage many polygons from an array in WKT format! This is where I've got to, mainly referencing this article: https://gis.stackexchange.com/a/141792/80756 which is the closest thing I can find to what I need:

// example array
fields = [];
fields.push('POLYGON((0.37865281105041504 52.715357357381926,0.3784811496734619 52.71480491657922,0.3788459300994873 52.71480491657922,0.37882447242736816 52.715370355904795,0.37865281105041504 52.715357357381926))');
fields.push('POLYGON((0.37668943405151367 52.71364151836265,0.37785887718200684 52.71366101691244,0.37789106369018555 52.714271967057215,0.37796616554260254 52.714414954153405,0.3783094882965088 52.714382457127265,0.3783094882965088 52.71463593328936,0.377429723739624 52.714655431394654,0.3774082660675049 52.714453950552866,0.37659287452697754 52.71446694934492,0.37668943405151367 52.71364151836265))');
fields.push('POLYGON((0.37491917610168457 52.71521437337461,0.3757345676422119 52.71533136032452,0.37583112716674805 52.714876409312474,0.37500500679016113 52.714791917887844,0.37491917610168457 52.71521437337461))');
fields.push('POLYGON((0.37282705307006836 52.71657920160306,0.37366390228271484 52.7165727025222,0.37358880043029785 52.715461345456504,0.3727841377258301 52.71552633787724,0.37282705307006836 52.71657920160306))');

// Set format
var format = new ol.format.WKT();

var polyCoords = [];
for (var i in fields) {
    polyCoords.push(format.readFeature(fields[i]).getGeometry().transform('EPSG:4326', 'EPSG:3857'));
}

var feature = new ol.Feature({
    geometry: new ol.geom.Polygon([polyCoords])
})

var fields_layer = new ol.layer.Vector({
  source: new ol.source.Vector({
    features: [feature]
  })
});

// add field layer to map (map is globally defined and I know this part works)
map.addLayer(fields_layer);

I'm new to OL3.

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to use geometries as WKT in OL3 you'll have to call an ol.format.WKT() and readGeometry, like this :

var wktFormat= new ol.format.WKT();
yourGeometry=wkt.readGeometry(yourWKTGeometry);
// and that's it you have a valid ol3 geometry now

in your code you are calling readFeature while you have a geometry instead

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