LibTest/typed_data/ByteData/getFloat32_A01_t01.dart

/*
 * Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 * for details. All rights reserved. Use of this source code is governed by a
 * BSD-style license that can be found in the LICENSE file.
 */
/**
 * @assertion double getFloat32(int byteOffset, [Endianness endian = Endianness.BIG_ENDIAN])
 * Returns the floating point number represented by the four bytes at
 * the specified [byteOffset] in this object, in IEEE 754
 * single-precision binary floating-point format (binary32).
 * @description Checks that the correct value is returned.
 * @author msyabro
 */

import "dart:typed_data";
import "../../../Utils/expect.dart";

main() {
  var f32 = new Float32List.fromList([.0, .12, 0.123e32, -0.312e-31, 10.0, 1.401298464324817e-45, 1.1754943508222875e-38]);
  var u32 = new Uint32List.fromList([0x62e7a17b, 0xf7ec7100, 0xe7180101, 0x1f83ccbb]);
  var sizeInBytes =  Float32List.BYTES_PER_ELEMENT;

  var byteDataFromF32 = new ByteData.view(f32.buffer);
  for(int i = 0; i < byteDataFromF32.lengthInBytes / sizeInBytes; ++i) {
    Expect.approxEquals(f32[i], byteDataFromF32.getFloat32(i*sizeInBytes, Endianness.LITTLE_ENDIAN),(f32[i]/1e7).abs());
  }

  var byteDataFromU32 = new ByteData.view(u32.buffer);
  var expectedBigEndian = [1.6813055904049544e+36, 1.0462418034594343e-38, 2.3711424564181874e-38, -0.006241216789931059];
  var expectedLittleEndian = [2.136416887544574e+21, -9.591202897651812e+33, -7.178182241978538e+23, 5.581935619425446e-20];
  for(int i = 0; i < byteDataFromU32.lengthInBytes / sizeInBytes; ++i) {
    Expect.approxEquals(expectedBigEndian[i], byteDataFromU32.getFloat32(i*sizeInBytes, Endianness.BIG_ENDIAN),
                        (expectedBigEndian[i]/1e7).abs());
    Expect.approxEquals(expectedLittleEndian[i], byteDataFromU32.getFloat32(i*sizeInBytes, Endianness.LITTLE_ENDIAN),
                        (expectedLittleEndian[i]/1e7).abs());
  }
}