Okay, so I’ve been messing around with R lately, trying to get some C code to work with it. It’s been… an experience. Let me tell you about it.
The Initial Idea
I had this C function, you see, that did some heavy number crunching. It was pretty optimized, but I wanted to use it within R, mostly because R is great for plotting and data analysis, and I am very familiar with it. and you know, making things look pretty. My initial thought was, “Hey, this shouldn’t be too hard, right? There’s gotta be a way to call C from R.” Famous last words.
Diving into the “r mex” Rabbit Hole
I started Googling like a madman. “R call C function,” “R interface with C,” that kind of stuff. I quickly stumbled upon this thing called “r mex”. And soon I found a function in R called “dotC()”, I can use it to call my c function.
It seemed to me that “r mex” is a basic way to compile the c function into a format I can use in R.
The Struggle Begins
First hurdle: I needed to write a wrapper function. This is basically a C function that acts as a bridge between R and my original C code. It takes R objects, converts them to C types, calls my original function, and then converts the results back to R objects. Sounds simple enough, but oh boy, the data type conversions were a pain. R has its own way of handling data, and making sure everything lined up with C’s expectations was… tedious.
- Integer conversions:R’s integers are not as simple as C integers. Got some weird errors there.
- Double conversions: Floating-point numbers, thankfully, were a bit smoother.
- Memory management:This is where things got really tricky. Making sure I didn’t leak memory or accidentally overwrite something important was a constant worry. I spent a good chunk of time just staring at memory addresses, trying to figure out what was going on.
Compilation Nightmares
Then came the compilation. I thought, “I’ll just use a regular C compiler, and It’s good to go!”. Nope. Had to figure out the compiler to use and how to link the R libraries correctly. Different operating systems, different setups… it was a mess. Error messages were cryptic, to say the least. I spent hours tweaking compiler flags, chasing down missing header files, and generally feeling like I was losing my mind.
Finally, Success (Sort Of)
After what felt like an eternity, I finally managed to compile my code. I held my breath, ran the R script, and… it worked! Well, mostly. There were a few glitches here and there, some weird edge cases that I hadn’t accounted for. But the core functionality was there. I could call my C function from R, and it was (relatively) fast.
The Aftermath
So, would I recommend this “r mex” adventure to others? Maybe. If you really need the speed of C and you’re comfortable with low-level programming, it might be worth it. But be prepared for a steep learning curve, a lot of frustration, and a whole bunch of debugging. I swear, I aged a year during this whole process.
But hey, at least I learned something. And I can now proudly say that I’ve wrestled with “r mex” and lived to tell the tale. It’s not pretty, but it’s my story, and it works(Now). Next time, I might just stick to R’s built-in functions, though. My sanity will thank me.