"""
演示
    张量元素类型的转换

设计到的API:
    data.to(torch.float32)
    data.type(torch.DoubleTensor)
    data.half/double/float/short/int/long()
需要掌握：
    data.to(dtype,device)

"""

# 导包
import torch

# 设置设备
device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
print(f"device:{device}")
# 1.定义函数，演示 张量的元素类型转换
def demo01():
    # 1.创建张量时，指定元素类型
    t1 = torch.tensor([[1,2,3],[4,5,6]], dtype=torch.float32)
    print(f"t1:{t1}, shape: {t1.shape}, dtype: {t1.dtype}, device: {t1.device}")
    # 2.使用data.to实现张量元素类型转换
    t2 = t1.to(dtype=torch.float64)
    print(f"t2:{t2}, shape: {t2.shape}, dtype: {t2.dtype}, device: {t2.device}")
    t2 = t2.to(device)
    print(f"t2:{t2}, shape: {t2.shape}, dtype: {t2.dtype}, device: {t2.device}")
    # 3.使用data.type实现张量元素类型转换
    t3 = t1.type(dtype=torch.float64)
    print(f"t3:{t3}, shape: {t3.shape}, dtype: {t3.dtype}, device: {t3.device}")
    # 4.使用data.double实现张量元素类型转换
    t4 = t1.double()
    print(f"t4:{t4}, shape: {t4.shape}, dtype: {t4.dtype}, device: {t4.device}")

# 测试
if __name__ == '__main__':
    demo01()