:orphan:
# KSP_DIVERGED_BREAKDOWN
A breakdown in the Krylov method was detected so the method could not continue to enlarge the Krylov space. Could be due to a singular matrix or preconditioner. In `KSPHPDDM`, this is also returned when some search directions within a block are colinear. 


## See Also
 [](ch_ksp), `KSPSolve()`, `KSPGetConvergedReason()`, `KSPConvergedReason`, `KSPSetTolerances()`

## Level
beginner

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

## Examples
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex77.c.html">src/ksp/ksp/tutorials/ex77.c</A><BR>


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