# Block randomization

**URL:** <https://discourse.psychopy.org/t/block-randomization/40452>\
**Category:** Builder\
**Created:** [June 17, 2024, 5:08pm UTC](https://discourse.psychopy.org/t/block-randomization/40452 "2024-06-17T17:08:57Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Guillaume\_GALLIOU](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.psychopy.org/guillaume_galliou/32/41461_2.png) [@Guillaume\_GALLIOU](https://discourse.psychopy.org/u/Guillaume_GALLIOU)\
**Post date:** [June 17, 2024, 5:08pm UTC](https://discourse.psychopy.org/t/block-randomization/40452/1 "2024-06-17T17:08:57Z")

</div>

Hello everyone

I suspect that this problem must have been widely studied but I have a block randomization problem.

**OS** (e.g. Win10): windows 10  
**PsychoPy version** (e.g. 1.84.x): Pyschopy 2023.2.3  
**Standard Standalone? (y/n)** If not then what?:  
**What are you trying to achieve?:**  
For experimental reasons, I have to randomize 12 different routines (a set image followed by a different image). the 12 routines must each return 5 times randomly.  
**What did you try to make it work?:**  
Coding is certainly very good, but I must recognize a glaring lack of skills on this subject. So I would prefer to use the builder.  
I built the program like this

 ![image](https://us1.discourse-cdn.com/flex002/uploads/psychopy/original/3X/7/9/7995b3977b7ca9a1ac032dfe20df69f8841762e7.png)

Each routine is made up of the same diagram  
 ![image](https://us1.discourse-cdn.com/flex002/uploads/psychopy/original/3X/4/d/4d5fc58a7da8e44f6e9bbeb8a5f66bccc0736adc.png)

and my randomization trial is this one  
 ![image](https://us1.discourse-cdn.com/flex002/uploads/psychopy/original/3X/f/5/f51f0a196c01611a6db9348c61a403adf2909107.png)

with an excel file like this  
 ![image](https://us1.discourse-cdn.com/flex002/uploads/psychopy/original/3X/5/a/5a060c60276a6ef6803431115b18fabb283b0347.png)

**What specifically went wrong when you tried that?:**  
There is no error message, I just have 5 times the same order of routines which follow one another.  
How to make the 5 times different.  
Thank you for your help