How do I generate a number between 1-180 (VEX EXP)

Programming Support VEXcode V5 Tech Support
1

How do I generate a number between 1-180 in vex exp

2

Depends on what language you are coding in.
Blocks is the easiest:
image

Python:
urandom.randint(1, 180)

C++ is more complicated:

#include <time.h> //for time

int main() {
  srand(time(NULL)); //set random seed
  
  Brain.Screen.print((rand() % 180)+1); //get random from 0 + 179 and then add 1 to result
}

I’m not sure how well this would work though because I don’t know how system time works on EXP, @jpearman might know a better way of doing this.

Side Note

When I tried this code using Mersenne twister:

Code 
//include random library
#include <random>

int main() {
  //setup random number generator
  std::random_device dev;
  std::mt19937 rng(dev());
  std::uniform_int_distribution<std::mt19937::result_type> dist180(1,180);

  //call random number
  Brain.Screen.print(dist180(rng));

}

I get this error:

Error

unix build for platform vexexp

CXX src/main.cpp

In file included from src/main.cpp:49:

In file included from /home/ubuntu/cloudcompiler/Tools/sdk/vexexp/20240219_10_00_00/gcc/include/c++/7.3.1/random:38:

/home/ubuntu/cloudcompiler/Tools/sdk/vexexp/20240219_10_00_00/gcc/include/c++/7.3.1/cmath:45:15: fatal error: ‘math.h’ file not found

#include_next <math.h>

^~~~~~~~

1 error generated.

make: *** [vex/mkrules.mk:13: build/src/main.o] Error 1

make process closed with exit code : 2

Does anyone know why this is happening?

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3

You must be using the cloud compiler, it still seems to on on an old version of the build system. That’s caused by an issue with toolchain include path order.

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4

Yeah, I’m on cloud compiler. Would that not be an issue on other platforms?

5

The desktop apps were updated, as was VSCode. I thought the cloud compile system had been, but apparently not. It’s an issue with #include_next in the system headers. It’s probably an issue for IQ2 as well, but using C++ standard library on IQ2 is often not viable due to lack of memory. I don’t think this was ever an issue for V5 (older version of system headers).

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