R language: integrate(function(x){8*x+2/5},0,10)
MATLAB language: vpa(int((8*x+2/5),0,10))
C programming with the GSL:
#include <stdio.h>
#include <math.h>
#include <gsl/gsl_integration.h>
double f(double x,void * params){
double f = 8*x+2./5;
return f;
}
int main (void){
gsl_integration_workspace * g = gsl_integration_workspace_alloc (1000);
double result, error;
gsl_function F;
F.function = &f;
gsl_integration_qags (&F,0,10,0,1e-7,1000,g,&result,&error);
printf("result= %.18f\n",result);
gsl_integration_workspace_free (g);
return 0;
} --------------------------------------------------------------------------------------
# g++ -Wall -I/usr/lib/include -c fun.c
# g++ fun.o -lgsl -lgslcblas -lm -o main.out
# ./main.out