我基本上试图在C代码中转换Matlab代码。这是我以前的question的延伸。使用C读取.mat文件:如何正确读取单元结构
在Matlab中,我已经使用cell-structures
保持matrices (double) of variable sizes
。这里是什么我* .MAT文件supposed to store
玩具例子:
MATLAB代码:
A = [[1 2 3]; [5 7 1]; [3 5 9]];
B = [[2 4];[5 7]];
Creator = 'DKumar';
nFilters = 2;
Filters{1} = [[-1.0 -1.0 -1.0]; [-1.0 8 -1.0]; [-1.0 -1.0 -1.0]];
Filters{2} = 2.0*[[-1.0 -1.0]; [-1.0 8]; [-1.0 -1.0]];
cd('/home/dkumar/CPP_ExampleCodes_DKU/Read_mat_File');
save('Test_FILE.mat', 'A', 'B', 'Creator', 'nFilters', 'Filters');
C代码:功能"matread_Matrix" reads matrices stored in *.mat properly
。这是功能"matread_Cell"
,它应该读取单元结构,是not working
。
#include <stdio.h>
#include <stdlib.h>
#include "/usr/local/MATLAB/R2011b/extern/include/mat.h"
mxArray *arr;
mxArray *C_CELL;
/* declare a 2 x 1 array of pointers to access the cell array in C */
mxArray *cellArray[2];
struct stDoubleMat{
double* pValueInField;
int nRows, nCols;
};
void matread_Matrix(const char *file, const char *FieldName2Read, struct stDoubleMat* poDoubleMat_LOC)
{
printf("Reading file %s...\n\n", file);
//Open file to get directory
MATFile* pmat = matOpen(file, "r");
if (pmat == NULL) {
printf("Error opening file %s\n", file);
return;
}
// extract the specified variable
arr = matGetVariable(pmat, FieldName2Read);
double *pr;
if (arr != NULL && !mxIsEmpty(arr)) {
// copy data
mwSize num = mxGetNumberOfElements(arr);
pr = mxGetPr(arr);
if (pr != NULL) {
poDoubleMat_LOC->pValueInField = pr;
poDoubleMat_LOC->nRows = mxGetM(arr);
poDoubleMat_LOC->nCols = mxGetN(arr);
}
printf("matread_Matrix \n") ;
printf("oDoubleMat_LOC.nRows %i ; oDoubleMat_LOC.nCols %i \n", poDoubleMat_LOC->nRows , poDoubleMat_LOC->nCols);
}else{
printf("nothing to read \n") ;
}
// close the file
matClose(pmat);
return;
}
void matread_Cell(const char *file, const char *FieldName2Read, int CellIndex)
{
printf("Reading file %s...\n\n", file);
//Open file to get directory
MATFile* pmat = matOpen(file, "r");
if (pmat == NULL) {
printf("Error opening file %s\n", file);
return;
}
// extract the specified variable
C_CELL = matGetVariable(pmat, FieldName2Read);
cellArray[CellIndex] = mxGetCell(C_CELL, CellIndex);
double* p2 = (double*)cellArray[CellIndex];
int nRows = mxGetM(cellArray[CellIndex]);
int nCols = mxGetN(cellArray[CellIndex]);
printf(" From inside matread_Cell : nRows %i and nCols %i \n", nRows, nCols);
int i2;
for (i2 = 0; i2 < nRows*nCols; i2++)
{
printf(" copied value : %f \n", *p2);
p2 = p2 +1;
}
// close the file
matClose(pmat);
}
int main(int argc, char **argv)
{
const char *FileName = "/home/dkumar/CPP_ExampleCodes_DKU/Read_mat_File/Test_FILE.mat";
const char *FieldName2Read = "A";
struct stDoubleMat oDoubleMat;
matread_Matrix(FileName, FieldName2Read, &oDoubleMat);
double* v = oDoubleMat.pValueInField;
printf("From main \n");
printf("oDoubleMat.nRows %i ; oDoubleMat.nCols %i \n", oDoubleMat.nRows , oDoubleMat.nCols);
int i;
for (i = 0; i < oDoubleMat.nCols*oDoubleMat.nRows; i++)
{
printf(" copied value : %f \n", *v);
v = v +1;
}
// Reading the structure
const char *FieldName2Read2 = "Filters";
matread_Cell(FileName, FieldName2Read2, 0);
matread_Cell(FileName, FieldName2Read2, 1);
// cleanup the mex-array
mxDestroyArray(arr);
mxDestroyArray(C_CELL);
/* How to delete mxArray of pointer : should this be a array of pointers */
//mxDestroyArray(cellArray[0]);
//mxDestroyArray(cellArray[1]);
return 0;
}
输出:
$ gcc -g -o Test Read_MatFile_DKU_2.c -I/usr/local/MATLAB/R2011b/extern/include -L/usr/local/MATLAB/R2011b/bin/glnxa64 -lmat -lmx
$ ./Test
Reading file /home/dkumar/CPP_ExampleCodes_DKU/Read_mat_File/Test_FILE.mat...
matread_Matrix
oDoubleMat_LOC.nRows 3 ; oDoubleMat_LOC.nCols 3
From main
oDoubleMat.nRows 3 ; oDoubleMat.nCols 3
copied value : 1.000000
copied value : 5.000000
copied value : 3.000000
copied value : 2.000000
copied value : 7.000000
copied value : 5.000000
copied value : 3.000000
copied value : 1.000000
copied value : 9.000000
Reading file /home/dkumar/CPP_ExampleCodes_DKU/Read_mat_File/Test_FILE.mat...
From inside matread_Cell : nRows 3 and nCols 3
copied value : 0.000000
copied value : 0.000000
copied value : 0.000000
copied value : 0.000000
copied value : 0.000000
copied value : 0.000000
copied value : 0.000000
copied value : 0.000000
copied value : 0.000000
Reading file /home/dkumar/CPP_ExampleCodes_DKU/Read_mat_File/Test_FILE.mat...
From inside matread_Cell : nRows 3 and nCols 2
copied value : 0.000000
copied value : 0.000000
copied value : 0.000000
copied value : 0.000000
copied value : 0.000000
copied value : 0.000000
另外,我不能读取该字段适当地以及:创建者= 'DKumar';
UPDATE:基于@Sherwin的建议
我的C代码:
#include <stdio.h>
#include <stdlib.h>
#include "/usr/local/MATLAB/R2011b/extern/include/mat.h"
mxArray *arr;
mxArray *C_CELL;
/* declare a 2 x 1 array of pointers to access the cell array in C */
mxArray *cellArray[2];
struct stDoubleMat{
double* pValueInField;
int nRows, nCols;
};
void matread_Matrix(MATFile* pmat , const char *FieldName2Read, struct stDoubleMat* poDoubleMat_LOC)
{
// extract the specified variable
arr = matGetVariable(pmat, FieldName2Read);
double *pr;
if (arr != NULL && !mxIsEmpty(arr)) {
// copy data
mwSize num = mxGetNumberOfElements(arr);
pr = mxGetPr(arr);
if (pr != NULL) {
poDoubleMat_LOC->pValueInField = pr;
poDoubleMat_LOC->nRows = mxGetM(arr);
poDoubleMat_LOC->nCols = mxGetN(arr);
}
printf("matread_Matrix \n") ;
printf("oDoubleMat_LOC.nRows %i ; oDoubleMat_LOC.nCols %i \n", poDoubleMat_LOC->nRows , poDoubleMat_LOC->nCols);
}else{
printf("nothing to read \n") ;
}
return;
}
void matread_String(MATFile* pmat , const char *FieldName2Read)
{
// extract the specified variable
arr = matGetVariable(pmat, FieldName2Read);
double *pr;
if (arr != NULL && !mxIsEmpty(arr)) {
// copy data
mwSize num = mxGetNumberOfElements(arr);
pr = mxGetPr(arr);
if (pr != NULL) {
char *p2 = (char*) pr;
// Printing and checking
int i2;
for (i2 = 0; i2 < num; i2++)
{
printf(" copied value : %s \n", p2);
p2 = p2 +1;
}
}
}else{
printf("nothing to read \n") ;
}
return;
}
void matread_Cell(MATFile* pmat , const char *FieldName2Read, int CellIndex)
{
// extract the specified variable
C_CELL = matGetVariable(pmat, FieldName2Read);
cellArray[CellIndex] = mxGetCell(C_CELL, CellIndex);
double *p2 = (double*) mxGetPr(cellArray[CellIndex]);
int nRows = mxGetM(cellArray[CellIndex]);
int nCols = mxGetN(cellArray[CellIndex]);
printf(" From inside matread_Cell : nRows %i and nCols %i \n", nRows, nCols);
int i2;
for (i2 = 0; i2 < nRows*nCols; i2++)
{
printf(" copied value : %f \n", *p2);
p2 = p2 +1;
}
}
int main(int argc, char **argv)
{
const char *FileName = "/home/dkumar/CPP_ExampleCodes_DKU/Read_mat_File/Test_FILE.mat";
const char *FieldName2Read = "A";
//Open file to get directory
printf("Reading file %s...\n\n", FileName);
MATFile* pmat = matOpen(FileName, "r");
if (pmat == NULL) {
printf("Error opening file %s\n", FileName);
return;
}
struct stDoubleMat oDoubleMat;
matread_Matrix(pmat, FieldName2Read, &oDoubleMat);
double* v = oDoubleMat.pValueInField;
int i;
for (i = 0; i < oDoubleMat.nCols*oDoubleMat.nRows; i++)
{
printf(" copied value : %f \n", *v);
v = v +1;
}
// Reading the structure
const char *FieldName2Read2 = "Filters";
matread_Cell(pmat, FieldName2Read2, 0);
matread_Cell(pmat, FieldName2Read2, 1);
// Reading the string
const char *FieldName2Read3 = "Creator";
matread_String(pmat, FieldName2Read3);
// cleanup the mex-array
mxDestroyArray(arr);
mxDestroyArray(C_CELL);
/* How to delete mxArray of pointer : should this be a array of pointers */
//mxDestroyArray(cellArray[0]);
//mxDestroyArray(cellArray[1]);
// close the file
matClose(pmat);
return 0;
}
输出:
oDoubleMat.nRows 3 ; oDoubleMat.nCols 3
copied value : 1.000000
copied value : 5.000000
copied value : 3.000000
copied value : 2.000000
copied value : 7.000000
copied value : 5.000000
copied value : 3.000000
copied value : 1.000000
copied value : 9.000000
From inside matread_Cell : nRows 3 and nCols 3
copied value : -1.000000
copied value : -1.000000
copied value : -1.000000
copied value : -1.000000
copied value : 8.000000
copied value : -1.000000
copied value : -1.000000
copied value : -1.000000
copied value : -1.000000
From inside matread_Cell : nRows 3 and nCols 2
copied value : -2.000000
copied value : -2.000000
copied value : -2.000000
copied value : -2.000000
copied value : 16.000000
copied value : -2.000000
copied value : D
copied value :
copied value : K
copied value :
copied value : u
copied value :
copied value :
问题:1)字符串值存储在创造者没有正确显示。
2)如何删除cellArray [2])?
如果你在Matlab之外读取数据,你为什么要将数据保存为“MAT”格式?为什么不将数据(在Matlab中)导出到例如hdf5并使用现有工具读取hdf5二进制数据? – Shai
我从来没有使用hdf5格式,我不知道它是否可以存储和访问单元格结构。 –
Matlab将其MAT文件保存为hdf5格式(适用于版本7.3及以上,AFAIK)。所以,原则上它可以做任何你需要的。你将不得不弄脏自己的手并学习如何连接到hdf5,但考虑到你正在经历与MAT格式相同(痛苦)的过程,我认为你会更好地学习更多功能的工具( HDF5),而不是专注于非常有限的MAT ...但这只是我的看法。 – Shai