         let filePath = tempFilePath()
 
         let file = createFile(filePath)
-        let dims: [UInt64] = [width, height]
+        let dims = [width, height]
         let dataspace = Dataspace(dims: dims)
-        XCTAssertEqual(dataspace.size, width * height)
-        XCTAssertEqual(dataspace.dims, dims)
+        XCTAssertEqual(Int(dataspace.size), width * height)
+        XCTAssertEqual(dataspace.dims.map{ Int($0) }, dims)
 
         let dataset = file.createDataset(datasetName, datatype: Datatype.createDouble(), dataspace: dataspace)
         XCTAssertNil(dataset.offset)

@testable import HDF5Kit

class FileTests: XCTestCase {
    let width = UInt64(100)
    let height = UInt64(100)
    let datasetName = "MyData"

    func writeData(filePath: String, data: [Double]) {

        }

        // Read as Float
        var actual = [Float](count: width*height, repeatedValue: 0.0)
        XCTAssert(dataset.readFloat(&actual))

        for i in 0..<expected.count {
