linux下GSL安装
背景：
Blei的hlda的C语言实现需要使用C语言的科学计算包GSL，因此决定安装。由于在windows下安装极其繁琐，先在Linux上安装之。
系统环境：
/usr/local/lib
If you ever happen to want to link against installed libraries
in a given directory, LIBDIR, you must either use libtool, and
specify the full pathname of the library, or use the `-LLIBDIR'
flag during linking and do at least one of the following:
- add LIBDIR to the `LD_LIBRARY_PATH' environment variable
during execution
- add LIBDIR to the `LD_RUN_PATH' environment variable
during linking
- use the `-Wl,--rpath -Wl,LIBDIR' linker flag
- have your system administrator add LIBDIR to `/etc/ld.so.conf'
See any operating system documentation about shared libraries for
more information, such as the ld(1) and ld.so(8) manual pages.
#include <stdio.h>
#include <gsl_rng.h>
#include <gsl_randist.h>
int main (int argc, char *argv[])
{
/* set up GSL RNG */
gsl_rng *r = gsl_rng_alloc(gsl_rng_mt19937);
/* end of GSL setup */
int i,n;
double gauss,gamma;
n=atoi(argv[1]);
for (i=0;i<n;i++)
{
gauss=gsl_ran_gaussian(r,2.0);
gamma=gsl_ran_gamma(r,2.0,3.0);
printf("%2.4f %2.4f\n", gauss,gamma);
}
return(0);
}（1）第一反应是直接 gcc gsl_test.c
显示错误是：gsl_test.c:2: fatal error: gsl_rng.h: 没有那个文件或目录
（2）这个错误是说没有找到头文件，然后加上头文件的位置，gcc -I/usr/local/include/gsl gsl_test.c
显示错误是：gsl_test.c:(.text+0x12): undefined reference to `gsl_rng_mt19937' ...
（3）这个错误是说没有找到gsl_rng_mt19937的定义，查看了http://www.daniweb.com/software-development/cpp/threads/289812/cant-link-gsl-properly，这里说需要加上-lgsl，即链接到gsl，找到 libgsl.so.
使用命令：gcc -I/usr/local/include/gsl -lgsl gsl_test.c
（4）显示错误是：//usr/local/lib/libgsl.so: undefined reference to `cblas_ctrmv'
查看了http://sourceware.org/ml/gsl-discuss/2003-q2/msg00123.html，是说错误是由于没有链接libgslcblas.so引起的，再加上-lgslcblas可以解决问题。
使用命令：gcc -I/usr/local/include/gsl -lgsl -lgslcblas gsl_test.c。
或者命令：gcc -I/usr/local/include/gsl -L/usr/local/lib -lgsl -lgslcblas gsl_test.c
这个时候出现了产出物a.out。
（5）运行a.out
./a.out 出现错误“段错误”
(6)查看源文件，发现还需要输入参数
./a.out 10
结果是：
0.2678 6.9645
3.3488 1.6894
1.9950 2.1575
-4.7934 6.1648
-0.0782 4.0292
1.7871 11.6031
-2.5931 7.7629
0.3634 1.3344
-1.0965 11.1658
0.0142 3.5412
彻底搞定，done#