Developer Reference for Intel® oneAPI Math Kernel Library for Fortran
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BLAS Level 1 Routines That Can Work With Sparse Vectors
The following BLAS Level 1 routines will give correct results when you pass to them a compressed-form array x(with the increment incx=1):
- ?asum
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sum of absolute values of vector elements
 - ?copy
 -  
    
copying a vector
 - ?nrm2
 -  
    
Euclidean norm of a vector
 - ?scal
 -  
    
scaling a vector
 - i?amax
 -  
    
index of the element with the largest absolute value for real flavors, or the largest sum |Re(x(i))|+|Im(x(i))| for complex flavors.
 - i?amin
 -  
    
index of the element with the smallest absolute value for real flavors, or the smallest sum |Re(x(i))|+|Im(x(i))| for complex flavors.
 
The result i returned by i?amax and i?amin should be interpreted as index in the compressed-form array, so that the largest (smallest) value is x(i); the corresponding index in full-storage array is indx(i).
You can also call ?rotg to compute the parameters of Givens rotation and then pass these parameters to the Sparse BLAS routines ?roti.