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[Lapack] Doubts regarding DGEQRF and DORGQR functions

Dear Sir,I am an amateur with LAPACK and I am confused about using the CLAPACK 
functions DGEQRF and DORGQR. Assuming I have a (10 x 2) matrix as the input 
matrix, how would I call the above functions?From my understanding, the input 
matrix should be converted to a 1D matrix in a column-major arrangement. So the 
input matrix (say A) becomes  a (1 x 20) matrix. Let,M = 10 (number of rows)N = 
2 (number of columns)LDA = ? (Leading Dimension of A. How do I calculate 
this?)TAU = (1 x MIN(M,N)) arrayWORK = ? (If I choose LWORK = -1, what should 
be the size of WORK?)LWORK = ? (How do I choose this value? Is it 
intuitive?)INFO (just declared, not defined)__CLPK_integer info1 = dgeqrf_(&M, 
&N, A, &LDA, TAU, WORK, &LWORK, &INFO);These calculations give me the desired 
value of R (from A) but how do I calculate Q? I don't clearly understand the 
working from the comments in the code.I would greatly appreciate your help in 
this regard.Thanks in advance,Nevine 
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