test_inversef.c on tough matrix to invert 
initializing big matrix, n=2, n*n=4 
data 
AA[0][0]=0.5 
AA[0][1]=0.333333 
AA[1][0]=0.333333 
AA[1][1]=0.25 
inverse 
AI[0][0]=18 
AI[0][1]=-24 
AI[1][0]=-24 
AI[1][1]=36 
AI[2][2]=36 
sum of error=5.16573e-07, avg error=1.29143e-07 
initializing big matrix, n=4, n*n=16 
data 
AA[0][0]=0.5 
AA[0][1]=0.333333 
AA[0][2]=0.25 
AA[0][3]=0.2 
AA[1][0]=0.333333 
AA[1][1]=0.25 
AA[1][2]=0.2 
AA[1][3]=0.166667 
AA[2][0]=0.25 
AA[2][1]=0.2 
AA[2][2]=0.166667 
AA[2][3]=0.142857 
AA[3][0]=0.2 
AA[3][1]=0.166667 
AA[3][2]=0.142857 
AA[3][3]=0.125 
inverse 
AI[0][0]=200.021 
AI[0][1]=-1200.15 
AI[0][2]=2100.29 
AI[0][3]=-1120.17 
AI[1][0]=-1200.15 
AI[1][1]=8101.08 
AI[1][2]=-15122.1 
AI[1][3]=8401.19 
AI[2][0]=2100.3 
AI[2][1]=-15122.1 
AI[2][2]=29404.1 
AI[2][3]=-16802.3 
AI[3][0]=-1120.17 
AI[3][1]=8401.21 
AI[3][2]=-16802.3 
AI[3][3]=9801.34 
AI[4][4]=9801.34 
sum of error=0.00125556, avg error=7.84726e-05 
initializing big matrix, n=8, n*n=64 
AI[8][8]=1.97304e+07 
sum of error=245.283, avg error=3.83254 
initializing big matrix, n=16, n*n=256 
AI[16][16]=1.91754e+08 
sum of error=3168.64, avg error=12.3775 
initializing big matrix, n=32, n*n=1024 
AI[32][32]=2.58953e+08 
sum of error=5329.34, avg error=5.20444 
initializing big matrix, n=64, n*n=4096 
AI[64][64]=1.26137e+08 
sum of error=25111, avg error=6.13062 
initializing big matrix, n=128, n*n=16384 
AI[128][128]=1.56788e+08 
sum of error=137508, avg error=8.39282 
initializing big matrix, n=256, n*n=65536 
AI[256][256]=1.15113e+10 
sum of error=7.47318e+07, avg error=1140.32 
initializing big matrix, n=512, n*n=262144 
AI[512][512]=4.38153e+09 
sum of error=1.93808e+07, avg error=73.9319 
initializing big matrix, n=1024, n*n=1048576 
AI[1024][1024]=-1.08234e+09 
sum of error=4.6584e+07, avg error=44.426 
finished test_inversef.c