实现一个任意1-4维的矩阵类 Tensor
请先阅读主程序，然后实现打印矩阵的函数：
void Tensor_print(int dimensions, const int sizes[], const double data[])
注意
由于只能打印出1维和2维的矩阵，当矩阵大于2维时需要按顺序打出高维矩阵中的各个2维矩阵
EXAMPLE INPUT
1.3
5.1
2.8
6.3
EXAMPLE OUTPUT
Tensor of 5
1.3
1.3
1.3
1.3
1.3
Tensor of 3x4
5.1 5.1 5.1 5.1
5.1 5.1 5.1 5.1
5.1 5.1 5.1 5.1
Tensor of 3x4x5
data[0]
2.8 2.8 2.8 2.8 2.8
2.8 2.8 2.8 2.8 2.8
2.8 2.8 2.8 2.8 2.8
2.8 2.8 2.8 2.8 2.8
data[1]
2.8 2.8 2.8 2.8 2.8
2.8 2.8 2.8 2.8 2.8
2.8 2.8 2.8 2.8 2.8
2.8 2.8 2.8 2.8 2.8
data[2]
2.8 2.8 2.8 2.8 2.8
2.8 2.8 2.8 2.8 2.8
2.8 2.8 2.8 2.8 2.8
2.8 2.8 2.8 2.8 2.8
Tensor of 2x3x4x5
data[0][0]
6.3 6.3 6.3 6.3 6.3
6.3 6.3 6.3 6.3 6.3
6.3 6.3 6.3 6.3 6.3
6.3 6.3 6.3 6.3 6.3
data[0][1]
6.3 6.3 6.3 6.3 6.3
6.3 6.3 6.3 6.3 6.3
6.3 6.3 6.3 6.3 6.3
6.3 6.3 6.3 6.3 6.3
data[0][2]
6.3 6.3 6.3 6.3 6.3
6.3 6.3 6.3 6.3 6.3
6.3 6.3 6.3 6.3 6.3
6.3 6.3 6.3 6.3 6.3
data[1][0]
6.3 6.3 6.3 6.3 6.3
6.3 6.3 6.3 6.3 6.3
6.3 6.3 6.3 6.3 6.3
6.3 6.3 6.3 6.3 6.3
data[1][1]
6.3 6.3 6.3 6.3 6.3
6.3 6.3 6.3 6.3 6.3
6.3 6.3 6.3 6.3 6.3
6.3 6.3 6.3 6.3 6.3
data[1][2]
6.3 6.3 6.3 6.3 6.3
6.3 6.3 6.3 6.3 6.3
6.3 6.3 6.3 6.3 6.3
6.3 6.3 6.3 6.3 6.3主程序 (不能修改)
#include "source.cpp"
#include <iostream>
using namespace std;
void _assert(bool valid, const char err_msg[]) {
if (valid) return;
cout << err_msg << endl;
exit(1);
}
class Tensor
{
private:
double * data;
int sizes[4];
int dimensions;
public:
Tensor(int size0, int size1=-1, int size2=-1, int size3=-1) {
_assert(size0 > 0, "第0维大小必须大于0");
if (size1 != -1) _assert(size1 > 0, "第1维大小必须大于0");
if (size2 != -1) _assert(size2 > 0, "第2维大小必须大于0");
if (size3 != -1) _assert(size3 > 0, "第3维大小必须大于0");
this->dimensions = 1;
this->sizes[0] = size0;
this->sizes[1] = this->sizes[2] = this->sizes[3] = 1;
if (size1 != -1) {
this->dimensions = 2;
this->sizes[1] = size1;
}
if (size2 != -1) {
this->dimensions = 3;
this->sizes[2] = size2;
}
if (size3 != -1) {
this->dimensions = 4;
this->sizes[3] = size3;
}
int totel_size = this->numel();
this->data = new double[totel_size];
for (int i = 0; i < totel_size; ++ i)
this->data[i] = 0;
}
int numel() { // number of elements
return this->sizes[0] * this->sizes[1] * this->sizes[2] * this->sizes[3];
}
void fill(double value) {
for (int i = 0; i < this->numel(); ++ i)
this->data[i] = value;
}
~Tensor() {
delete [] this->data;
}
double & get(int x0, int x1=-1, int x2=-1, int x3=-1) {
// 检查有否越界
_assert(x0 >= 0 && x0 < this->sizes[0], "第0维越界");
_assert((this->dimensions < 2 && x1 == -1) || (x1 >= 0 && x1 < this->sizes[1]), "第1维越界");
_assert((this->dimensions < 3 && x2 == -1) || (x2 >= 0 && x2 < this->sizes[2]), "第2维越界");
_assert((this->dimensions < 4 && x3 == -1) || (x3 >= 0 && x3 < this->sizes[3]), "第3维越界");
int index = x0;
if (this->dimensions > 1) index = index * this->sizes[1] + x1;
if (this->dimensions > 2) index = index * this->sizes[2] + x2;
if (this->dimensions > 3) index = index * this->sizes[3] + x3;
return this->data[index];
}
void print() const {
return Tensor_print(this->dimensions, this->sizes, this->data);
}
};
int main() {
double value;
// 测试1
Tensor t1(5);
cin >> value;
t1.fill(value);
t1.print();
cout << endl;
// 测试2
Tensor t2(3, 4);
cin >> value;
t2.fill(value);
t2.print();
cout << endl;
// 测试3
Tensor t3(3, 4, 5);
cin >> value;
t3.fill(value);
t3.print();
cout << endl;
// 测试4
Tensor t4(2, 3, 4, 5);
cin >> value;
t4.fill(value);
t4.print();
}参考答案
#include <iostream>
using namespace std;
void Tensor_print(int dimensions, const int sizes[], const double data[]){
if(dimensions==1){
cout << "Tensor of "<<sizes[0]<< endl;
for (int i = 0; i <sizes[0]; ++ i){
cout << data[i] <<endl;
}
}
else if(dimensions==2) {
cout << "Tensor of "<<sizes[0]<<"x"<<sizes[1]<< endl;
for (int i = 0; i <sizes[0]; ++ i){
for (int j = 0; j <sizes[1]; ++ j) {
cout << " " << data[i*sizes[1]+j];
}
cout<<endl;
}
}
else if(dimensions==3) {
cout << "Tensor of "<<sizes[0]<<"x"<<sizes[1]<<"x"<<sizes[2]<< endl;
for (int i = 0; i <sizes[0]; ++ i){
cout<<"data["<<i<<"]"<<endl;
for (int j = 0; j <sizes[1]; ++ j) {
for (int k = 0; k <sizes[2]; ++ k) {
cout << " " << data[i*sizes[1]*sizes[2]+j*sizes[2]+k];
}
cout<<endl;
}
}
}
else if(dimensions==4) {
cout << "Tensor of "<<sizes[0]<<"x"<<sizes[1]<<"x"<<sizes[2]<<"x"<<sizes[3]<< endl;
for (int i = 0; i <sizes[0]; ++ i){
for (int j = 0; j <sizes[1]; ++ j) {
cout<<"data["<<i<<"]["<<j<<"]"<<endl;
for (int k = 0; k <sizes[2]; ++ k) {
for (int l = 0; l <sizes[3]; ++ l) {
cout << " " << data[i*sizes[1]*sizes[2]*sizes[3]+j*sizes[2]*sizes[3]+k*sizes[3]+l];
}
cout<<endl;
}
}
}
}
}
//Provided by Yizuodi