Delete

Delete[expr,n] deletes the element at position n in expr. If n is negative, the position is counted from the end. 

Delete[expr,{i,j,…}] deletes the part at position {i,j,…}. 

Delete[expr,{{i1,j1,…},{i2,j2,…},…}] deletes parts at several positions. 

Delete[pos] represents an operator form of Delete that can be applied to an expression.

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