Geohash: Difference between revisions

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@@ Line 907: / Line 907: @@
 Geohash for: 57.64911 N, 10.40744 E, precision = 11 : u4pruydqqvj
 </pre>
+=={{header|Vlang}}==
+{{trans|go}}
+<lang vlang>struct Location {
+    lat f64
+    lng f64
+}
+fn (loc Location) str() string { return "[$loc.lat, $loc.lng]" }
+struct Range {
+    lower f64
+    upper f64
+}
+const g_base32 = "0123456789bcdefghjkmnpqrstuvwxyz"
+fn encode_geo_hash(loc Location, prec int) string {
+    mut lat_range := Range{-90, 90}
+    mut lng_range := Range{-180, 180}
+    mut hash := ''
+    mut hash_val := u32(0)
+    mut bits := 0
+    mut even := true
+    for hash.len < prec {
+        mut val := loc.lat
+        mut rng := lat_range
+        if even {
+            val = loc.lng
+            rng = lng_range
+        }
+        mid := (rng.lower + rng.upper) / 2
+        if val > mid {
+            hash_val = (hash_val << 1) + 1
+            rng = Range{mid, rng.upper}
+            if even {
+                lng_range = Range{mid, lng_range.upper}
+            } else {
+                lat_range = Range{mid, lat_range.upper}
+            }
+        } else {
+            hash_val <<= 1
+            if even {
+                lng_range = Range{lng_range.lower, mid}
+            } else {
+                lat_range = Range{lat_range.lower, mid}
+            }
+        }
+        even = !even
+        if bits < 4 {
+            bits++
+        } else {
+            bits = 0
+            hash+=g_base32[hash_val..hash_val+1]
+            hash_val = u32(0)
+        }
+    }
+    return hash.str()
+}
+fn main() {
+    locs := [Location{51.433718, -0.214126},
+        Location{51.433718, -0.214126},
+        Location{57.64911, 10.40744},
+    ]
+    precs := [2, 9, 11]
+    for i, loc in locs {
+        geohash := encode_geo_hash(loc, precs[i])
+        println("geohash for $loc, precision ${precs[i]:-2} = $geohash")
+    }
+}</lang>
+{{out}}
+<pre>geohash for [51.433718, -0.214126], precision 2  = gc
+geohash for [51.433718, -0.214126], precision 9  = gcpue5hp4
+geohash for [57.649110, 10.407440], precision 11 = u4pruydqqvj</pre>
 =={{header|Wren}}==