Charts: stratified random samplin base on a target

[reza1615]

Now the random sampling for charts doest apply stratified
sampling based on target.
It would be helpful to have a drop down to set the target column and generate stratified samples based on that.
It will help to have the same distribution of the whole data set.

[harshithakolipaka]

hey, I would like to work on this issue. Can you help me direct to the source code so that I can add the feature

[aschonfeld]

@harshithakolipaka thanks for your interest in this feature! Ok so to give you some background on how this will work you'll have to update the run_query function to have a boolean named parameter stratified_random_sample. So it will look something like this

run_query(
          handle_predefined(data_id),
          query,
          global_state.get_context_variables(data_id),
          pct=inputs.get("load"),
          pct_type=inputs.get("load_type"),
          stratified_random_sample=True
)

The run_query function is located here

The idea is that you'll want to check this boolean parameter and if its True then you'll run your random sampling code. You'll want to run it on the df parameter passed into run_query, it's the dataframe you've loaded into D-Tale. You'll probably want to call that function before anything else in run_query. Lastly, your random sampling function will return a dataframe that will later be used in the rest of the run_query function.

Honestly, if you'd just like to provide the random sampling function I can plug in the rest and make sure you still get credit for the code you've committed. Let me know if you have any other questions. Thanks

[aschonfeld]

@reza1615 I'm looking to implement this but wanted to know which of these two solutions were more suitable:

• https://stackoverflow.com/a/44115314
• https://stackoverflow.com/a/74493296 (and if this one what should the value of sampling_rate be set to and would an input be made available on the UI for this?)

[reza1615]

@reza1615 I'm looking to implement this but wanted to know which of these two solutions were more suitable:

• https://stackoverflow.com/a/44115314
• https://stackoverflow.com/a/74493296 (and if this one what should the value of sampling_rate be set to and would an input be made available on the UI for this?)

Hi, the second one. The sampling_rate is the ratio that we choose to down sample data. already you have it for down sampling. for example if user select 30% from UI the sample_rate is 0.3

[reza1615]

[aschonfeld]

@reza1615 @harshithakolipaka just realeased v2.15.0 with this feature. Let me
Know if you have any issues