:orphan:
# TSMonitorError
Monitors progress of the `TS` solvers by printing the 2 norm of the error at each timestep 
## Synopsis
```
#include "petscts.h"  
PetscErrorCode TSMonitorError(TS ts, PetscInt step, PetscReal ptime, Vec u, PetscViewerAndFormat *vf)
```
Collective


## Input Parameters

- ***ts -*** the `TS` context
- ***step -*** current time-step
- ***ptime -*** current time
- ***u -*** current solution
- ***dctx -*** unused context



## Options Database Key

- ***-ts_monitor_error -*** create a graphical monitor of error history





## Notes
This is not called directly by users, rather one calls `TSMonitorSet()`, with this function as an argument, to cause the monitor
to be used during the `TS` integration.

The user must provide the solution using `TSSetSolutionFunction()` to use this monitor.


## See Also
 [](ch_ts), `TS`, `TSMonitorSet()`, `TSMonitorDefault()`, `VecView()`, `TSSetSolutionFunction()`

## Level
intermediate

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/interface/tsmon.c.html#TSMonitorError">src/ts/interface/tsmon.c</A>


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[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/ts/interface/tsmon.c)


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