# time signature for variable time steps
**URL:** https://discourse.paraview.org/t/time-signature-for-variable-time-steps/2427
**Category:** ParaView Support
**Created:** [August 14, 2019, 8:10am UTC](https://discourse.paraview.org/t/time-signature-for-variable-time-steps/2427 "2019-08-14T08:10:37Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@mmainak](https://discourse.paraview.org/u/mmainak)
#### Post date: [August 14, 2019, 8:10am UTC](https://discourse.paraview.org/t/time-signature-for-variable-time-steps/2427/1 "2019-08-14T08:10:37Z")
Hi. I am outputing vtk file with variable time steps. However the file series are named like data\_parav\_000n.vtk, where n is the time steps. However for a variable time stepping n does not corresponds to the physical time. I am outputing vtk file as rectiliniar grid and the header looks like the following
```
# vtk DataFile Version 3.0data_parav
BINARY
DATASET RECTILINEAR_GRID
DIMENSIONS 1 257 1153
X_COORDINATES 1 float
#### (number)
Y_COORDINATES 257 float
#############(257 numbers)
SCALAR Temp_d float 1
LOOKUP_TABLE default
###########
```
and other scalar parameters
How do I add actual physical time in the paraview time series?
---
### Author:  [@mmainak](https://discourse.paraview.org/u/mmainak)
#### Post date: [August 20, 2019, 8:58am UTC](https://discourse.paraview.org/t/time-signature-for-variable-time-steps/2427/2 "2019-08-20T08:58:32Z")
It’s unfortunate no one is even bother to answer. Had it already been discussed somewhere it would help if you can point it out.
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### Author:  [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [August 20, 2019, 9:31am UTC](https://discourse.paraview.org/t/time-signature-for-variable-time-steps/2427/3 "2019-08-20T09:31:29Z")
.vtk file is a legacy format and do not support specifying the time value.
You can have timesteps as a time series.
[https://www.paraview.org/Wiki/Animating\_legacy\_VTK\_file\_series](https://www.paraview.org/Wiki/Animating_legacy_VTK_file_series)
In any case, I would suggest using a more modern format, like vtu or vtp.
---
### Author:  [@mmainak](https://discourse.paraview.org/u/mmainak)
#### Post date: [August 21, 2019, 12:00am UTC](https://discourse.paraview.org/t/time-signature-for-variable-time-steps/2427/4 "2019-08-21T00:00:52Z")
Thanks Mathieu Westphal