pytorch-第一章基本操作-基本使用方法 (1.torch.empty, 2.torch.rand, 3.torch.zeros, 4.torch.tensor, 5.x.new_ones，6.torch.rand_like, 7.torch.randn, 8.torch.from_numpy, 9.x.view(改變維度))

import torch


x = torch.empty(5, 3) # 生成空的矩陣
print(x)

x = torch.rand(5, 4) # 生成隨機矩陣
print(x)


x = torch.zeros(5, 4, dtype=torch.long) # 生成空矩陣
print(x)

x = torch.tensor([5, 3]) # 將列表轉換維tensor類型
print(x)

x = x.new_ones([5, 3], dtype=torch.double) # 構造全1的數組
print(x)
x = torch.rand_like(x, dtype=torch.float) # 生成相同維度的隨機矩陣
print(x.size())

y = torch.rand(5, 3) # 構造隨機的矩陣
print(x + y)

torch.add(x, y) # 進行矩陣的相加操作

# 索引
print(x[:, 1])

# view操作可以改變矩陣維度

x = torch.randn(4, 4)
y = x.view(16)
z = x.view(-1, 8)

a = torch.ones(5)  # tensor
b = a.numpy()  # 將tensor轉換為numpy格式

import numpy as np
a = np.ones([3, 2])
b = torch.from_numpy(a) # 將a轉換為tensor格式
print(b)