I want to realize IFFT function by CUDA. Input data is complex. The real numbers are imported from phase_init_befroe_R.csv, and the imaginary numbers are imported from phase_init_before_C.csv. Then I run the cufftExecC2C or the cufftExecZ2Z function. The result is saved in out_R.csv and out_C.csv. out_R.csv is what I want.
When the macro SINGLE is defined, all the data will be single-precision. Here is the result drawn by Matlab command imagesc(csvread("out_R.csv"):

All files are uploaded to Google Driver. Here is the link:https://drive.google.com/drive/folders/1aQZOxVAFe82W9LyvYzfgmfkas8vsqC2Q?usp=sharing

When the macro SINGLE is not defined, all the data will be in double-precision. Drawn by Matlab command imagesc(csvread("out_R.csv")):

I verify the result using Matlab. Whether the data is single- or double-precision in Matlab, the result is same. And it is similar to the second image.

Why is single-precision data leading to wrong out_R.csv?

#include <iostream>
#include <cufft.h>
#include <fstream>

#pragma comment(lib,"cufft.lib")

#define ROW 120
#define COL 160

using namespace std;

// change precision between single and double
//#define SINGLE

#ifdef SINGLE
#define REAL cufftReal
#define COMPLEX cufftComplex
#else
#define REAL cufftDoubleReal
#define COMPLEX cufftDoubleComplex
#endif


// read file csv file
template <typename T>
void readData(T* inputData, const char* fileName)
{
    ifstream file;
    file.open(fileName);
    if(file.is_open())
    {
        for(int i = 0; i<ROW*COL; ++i)
        {
                file>>*inputData++;
                file.get();
        }
        file.close();
    }
    else{
        printf("Can not open file %s", fileName);
    }
}

// save to csv file
template<typename T>
void saveData(T* inputData, const char* fileName, bool realOrImag)
{
    ofstream file;
    file.open(fileName);
    if(file.is_open())
    {
        for(int i = 0; i<ROW; ++i)
        {
            for(int j=0; j<COL; ++j)
            {
                int index = i*COL+j;
                if(j<COL-1)
                {
                    if(realOrImag)
                    {
                        file<<(*inputData).x<<",";
                    }
                    else{
                        file<<(*inputData).y<<",";
                    }

                    inputData++;
                }
                else
                {
                    if(realOrImag)
                    {
                        file<<(*inputData).x<<"n";

                    }
                    else{
                        file<<(*inputData).y<<"n";
                    }
                    inputData++;
                }
            }
        }
    }
}

template<typename T>
void showData(T* inputData)
{
    for(int i=0; i<6; ++i)
    {
        for(int j = 0; j<3; ++j)
        {
            printf("(%.3f, %.3f)t", inputData[i*COL+j].x, inputData[i*COL+j].y);
        }
        printf("n");
    }
}

int main() {

    // read data from csv file
    REAL *real, *imag;
    real = (REAL*)malloc(ROW*COL*sizeof(REAL));
    imag = (REAL*)malloc(ROW*COL*sizeof(REAL));
    readData(real, R"(C:UsersadminDocumentsMATLABphase_init_before_R.csv)");
    readData(imag, R"(C:UsersadminDocumentsMATLABphase_init_before_C.csv)");

    COMPLEX *in;
    in = (COMPLEX*)malloc(ROW*COL*sizeof(COMPLEX));
    for(int m = 0; m<ROW*COL; ++m)
    {
        in[m] = {real[m], imag[m]};
    }

    // copy form host to device
    COMPLEX *in_dev;
    cudaMalloc(&in_dev, ROW*COL*sizeof(COMPLEX));
    cudaMemcpy(in_dev, in, ROW*COL*sizeof(COMPLEX), cudaMemcpyHostToDevice);

    // IFFT
#ifdef SINGLE
    cufftHandle handle;
    cufftPlan2d(&handle, ROW, COL, CUFFT_C2C);
    cufftExecC2C(handle, in_dev, in_dev, CUFFT_INVERSE);
#else
    cufftHandle handle;
    cufftPlan2d(&handle, ROW, COL, CUFFT_Z2Z);
    cufftExecZ2Z(handle, in_dev, in_dev, CUFFT_INVERSE);
#endif

    // copy from device to host
    COMPLEX *out;
    out = (COMPLEX*)malloc(ROW*COL*sizeof(COMPLEX));
    cudaMemcpy(out, in_dev, ROW*COL*sizeof(COMPLEX), cudaMemcpyDeviceToHost);

    // save to csv file
    saveData(out, R"(C:UsersadminDocumentsMATLABout_R.csv)", true);
    saveData(out, R"(C:UsersadminDocumentsMATLABout_C.csv)", false);

    cudaFree(in_dev);
    free(in);
    free(out);
    free(real);
    free(imag);
    cufftDestroy(handle);

    return 0;
}

At first, to make it work fast, all data is in single precision. But the result is wrong. I checked the syntax and it is correct. So I tried to change the data type from single-precision to double-precision. It happened to produce the correct answer.