# KSP_DIVERGED_DTOL
norm(r) >= dtol*norm(b) 

See `KSPNormType` and `KSPSetNormType()` for possible norms that may be used. By default
for left preconditioning it is the 2-norm of the preconditioned residual, and the
2-norm of the residual for right preconditioning




## See Also
 `KSP_CONVERGED_ATOL`, `KSP_DIVERGED_RTOL`, `KSPSolve()`, `KSPGetConvergedReason()`, `KSPConvergedReason`, `KSPSetTolerances()`


## Level
beginner

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/include/petscksp.h.html#KSP_DIVERGED_DTOL">include/petscksp.h</A>


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[Index of all KSP routines](index.md)  
[Table of Contents for all manual pages](/docs/manualpages/index.md)  
[Index of all manual pages](/docs/manualpages/singleindex.md)  
