I have an existing R script that performs various operations, and I'm looking to create a C sub function to optimize a specific part of it. My goal is to integrate this C sub function within R Desktop for improved performance and efficiency.
For example, let's assume that I want to sum the elements obtained by multiplying the vector x and y. In R, I can achieve this with the following code:
# R code
x <- c(1, 2, 3)
y <- c(4, 5, 6)
z <- sum(x * y)
The same operation using oneMKL can be performed like this:
#include <stdio.h>
#include <mkl.h>
int main() {
double x[] = {1.0, 2.0, 3.0};
double y[] = {4.0, 5.0, 6.0};
double z;
// Perform vector multiplication and summation using Intel MKL
z = cblas_ddot(3, x, 1, y, 1);
printf("Result: %lf\n", z);
return 0;
}
After compiling the .c function using CMD, I get:
C:\Program Files (x86)\Intel\oneAPI>cd C:/Users/Administrator/Desktop
C:\Users\Administrator\Desktop>icx -o example example.c /Qmkl /MD
Intel(R) oneAPI DPC++/C++ Compiler for applications running on Intel(R) 64, Version 2023.1.0 Build 20230320
Copyright (C) 1985-2023 Intel Corporation. All rights reserved.
C:\Users\Administrator\Desktop>example.exe
Result: 32.000000
What I want to do is replace the 4th line of the Rscript code with a .c function. I'm facing two problems:
1) Convert the C Function for General Inputs:
I don't know if I have defined the function correctly.
#include <stdio.h>
#include <mkl.h>
void multiplyAndSum(double *x, double *y, int length, double *result) {
*result = cblas_ddot(length, x, 1, y, 1);
}
2) Calling the C Function in R:
I don't know how to call the .c function in step 1 within R. Is there a way to compile the function and run it explicitly within R Desktop, without using the command prompt (cmd)
Please, I understand that my question may be quite basic, but my knowledge is limited. I would greatly appreciate a step-by-step answer, ideally.
