如何在ASSOCIATE塊中保留Fortran數組邊界？

Question

我想在聯想塊保存數組邊界爲：

integer a(2:4,2) 
associate (b => a(:,1)) 
    print *, lbound(b), ubound(b) 
end associate 

我想到的是b和2的4界限，但實際上他們是1和3。這個怎麼做？提前致謝！

Answer 1

您關聯到一個子陣，它的邊界始終從1開始嘗試

print *, lbound(a(:,1),1) 

AFAIK你不能在associate結構使用指針重映射伎倆。具體做法是：「If the selector is an array, the associating entity is an array with a lower bound for each dimension equal to the value of the intrinsic LBOUND(selector).」

但是，你當然可以用指針

integer,target :: a(2:4,2) 

integer,pointer :: c(:) 


associate (b => a(:,1)) 
    print *, lbound(b), ubound(b) 
end associate 

c(2:4) => a(:,1) 
print *, lbound(c), ubound(c) 

end 

Answer 2

我認爲要保持數組邊界更優雅的方式將做到以下幾點：

integer,target :: a(2:4,2) 
integer,pointer :: b(:) 

b(lbound(a,1):) => a(:,1)