在DolphinDB database中有如下矩阵:
m=take(1 2 3 4,12) join take(int(),4) join take(1 2 3 4,8) join take(int(),8) join 1 2 3 4 $ 12:3
for(i in 0..(m.rows()-1)){ for(j in 0..(m.cols()-1)){ if(isNull(m[i,j])==true){ m[i,j]=1 break } } }