l still don't understand 'N' , 'T' . Any clarifications please ?

TRANSA = 'N' or 'n',  op( A ) = A.

 TRANSA = 'T' or 't',  op( A ) = A'.

TRANSB = 'N' or 'n',  op( B ) = B.

 TRANSB = 'T' or 't',  op( B ) = B'.

 TRANSB = 'C' or 'c',  op( B ) = B'.


On Wed, Jul 20, 2016 at 3:36 PM, Steven G. Johnson <[email protected]>
wrote:

>
>
> On Wednesday, July 20, 2016 at 9:33:37 AM UTC-4, Ahmed Mazari wrote:
>>
>> l'm new to julia. l want to use the Blas package. To do so, the meaning
>> of the two first parameters of gemm function are less evident for me What
>> the parameters 'N', 'T' represent?
>>
>
> Those exactly correspond to arguments to the Fortran dgemm subroutine (
> http://www.math.utah.edu/software/lapack/lapack-blas/dgemm.html).  They
> indicate whether the matrices are to be treated as transposed.
>
>
>>  BLAS.gemm!('N', 'T', lr,  alpha, A, B, beta, C)
>>
>> What is the difference between BLAS.gemm and BLAS.gemm! ?
>>
>
> The convention in Julia is that appending an exclamation mark (e.g. gemm!)
> indicates that the function modifies one of its arguments in-place, whereas
> gemm allocates a new array for the result.
>

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