fix: write binary table keeping data

column.go

@@ -417,12 +417,15 @@ func (col *Column) writeBin(table *Table, icol int, irow int64, ptr interface{})
 		}
 
 	case reflect.Array:
+		rvPtr := reflect.New(rv.Type()).Elem()
+		rvPtr.Set(rv)
 
 		beg := table.rowsz*int(irow) + col.offset
 		end := beg + (col.dtype.dsize * col.dtype.len)
 
 		w := newWriter(table.data[beg:end])
-		switch slice := rv.Slice(0, rv.Len()).Interface().(type) {
+
+		switch slice := rvPtr.Slice(0, rv.Len()).Interface().(type) {
 		case []bool:
 			w.writeBools(slice)
 

table.go

@@ -412,12 +412,10 @@ func (t *Table) writeMap(data map[string]interface{}) error {
 
 	for _, icol := range icols {
 		col := t.Col(icol)
-		val := reflect.New(col.Type())
-		err = col.write(t, icol, t.nrows, val.Interface())
+		err = col.write(t, icol, t.nrows, data[col.Name])
 		if err != nil {
 			return err
 		}
-		data[col.Name] = val.Elem().Interface()
 	}
 	return err
 }

table_test.go

@@ -2046,6 +2046,10 @@ func TestTableMapsRW(t *testing.T) {
 				},
 				{
 					Name:   "E",
+					Format: "10A",
+				},
+				{
+					Name:   "F",
 					Format: "2D",
 				},
 			},
@@ -2056,28 +2060,32 @@ func TestTableMapsRW(t *testing.T) {
 					"B": float64(10),
 					"C": []int64{10, 10},
 					"D": []float64{10, 10},
-					"E": [2]float64{10, 10},
+					"E": string("10"),
+					"F": [2]float64{10, 10},
 				},
 				{
 					"A": int64(11),
 					"B": float64(11),
 					"C": []int64{11, 11},
 					"D": []float64{11, 11},
-					"E": [2]float64{11, 11},
+					"E": string("11"),
+					"F": [2]float64{11, 11},
 				},
 				{
 					"A": int64(12),
 					"B": float64(12),
 					"C": []int64{12, 12},
 					"D": []float64{12, 12},
-					"E": [2]float64{12, 12},
+					"E": string("12"),
+					"F": [2]float64{12, 12},
 				},
 				{
 					"A": int64(13),
 					"B": float64(13),
 					"C": []int64{13, 13},
 					"D": []float64{13, 13},
-					"E": [2]float64{13, 13},
+					"E": string("13"),
+					"F": [2]float64{13, 13},
 				},
 			},
 		},