Data Visualization Example with lets-plot does not work.

[muthenberg]

Hi,

I would like to do some data visualization using krangl and lets-plot. I tried to get the example working. For this I created a new jupyter-lab notebook with a single section containing the following code from the example:

%use krangl(0.17)
%use lets-plot

var sleepDataExt = sleepData.addColumn("rem_proportion"){it["sleep_rem"]/it["sleep_total"]}
sleepDataExt.letsPlot {x="sleep_total"; y="rem_proportion" } + geomPoint()

Upon execution I get an error message stating: Line_58.jupyter-kts (5:64 - 75) Type mismatch: inferred type is geomPoint but Feature was expected

Did I do something wrong? Is this a known bug? Is there a workaround?

Thanks and regards

[holgerbrandl]

Please use the latest version 0.18.2. For me this seems to work, could you confirm?

[muthenberg]

I changed the Code to:

%use krangl(0.18.4)
%use lets-plot

var sleepDataExt = sleepData.addColumn("rem_proportion"){it["sleep_rem"]/it["sleep_total"]}
sleepDataExt.letsPlot {x="sleep_total"; y="rem_proportion" } + geomPoint()

But I still get:

Line_69.jupyter-kts (4:64 - 75) Type mismatch: inferred type is geomPoint but Feature was expected

On the terminal where my Jupyter-Lab is running I get the following output related to this error message. Is this of any use to you?

334831555 [main] DEBUG SocketWrapper - [SHELL] snd>: msg[f92e6a1e-84bb-45dd-bf52-e446681faeae] 
{
  "header": {
    "msg_id": "42739e09-1c8c-4632-81d4-f1f28c5a3cf4",
    "msg_type": "execute_reply",
    "session": "f92e6a1e-84bb-45dd-bf52-e446681faeae",
    "username": "",
    "version": "5.3",
    "date": "2022-08-29T10:58+0200"
  },
  "parent_header": {
    "msg_id": "e0382a18-f211-439f-9fc3-88c199dc4c92",
    "msg_type": "execute_request",
    "session": "f92e6a1e-84bb-45dd-bf52-e446681faeae",
    "username": "",
    "version": "5.2",
    "date": "2022-08-29T08:58:08.204Z"
  },
  "metadata": null,
  "content": {
    "status": "error",
    "execution_count": 12,
    "ename": "org.jetbrains.kotlinx.jupyter.exceptions.ReplCompilerException",
    "evalue": "Line_69.jupyter-kts (4:64 - 75) Type mismatch: inferred type is geomPoint but Feature was expected",
    "traceback": [
      "org.jetbrains.kotlinx.jupyter.repl.impl.JupyterCompilerImpl.compileSync(JupyterCompilerImpl.kt:174)",
      "org.jetbrains.kotlinx.jupyter.repl.impl.InternalEvaluatorImpl.eval(InternalEvaluatorImpl.kt:99)",
      "org.jetbrains.kotlinx.jupyter.repl.impl.CellExecutorImpl$execute$1$result$1.invoke(CellExecutorImpl.kt:71)",
      "org.jetbrains.kotlinx.jupyter.repl.impl.CellExecutorImpl$execute$1$result$1.invoke(CellExecutorImpl.kt:69)",
      "org.jetbrains.kotlinx.jupyter.ReplForJupyterImpl.withHost(repl.kt:635)",
      "org.jetbrains.kotlinx.jupyter.repl.impl.CellExecutorImpl.execute(CellExecutorImpl.kt:69)",
      "org.jetbrains.kotlinx.jupyter.repl.CellExecutor$DefaultImpls.execute$default(CellExecutor.kt:15)",
      "org.jetbrains.kotlinx.jupyter.ReplForJupyterImpl$evalEx$1.invoke(repl.kt:444)",
      "org.jetbrains.kotlinx.jupyter.ReplForJupyterImpl$evalEx$1.invoke(repl.kt:433)",
      "org.jetbrains.kotlinx.jupyter.ReplForJupyterImpl.withEvalContext(repl.kt:397)",
      "org.jetbrains.kotlinx.jupyter.ReplForJupyterImpl.evalEx(repl.kt:433)",
      "org.jetbrains.kotlinx.jupyter.ReplForJupyterImpl.eval(repl.kt:485)",
      "org.jetbrains.kotlinx.jupyter.messaging.ProtocolKt$shellMessagesHandler$2$res$1.invoke(protocol.kt:321)",
      "org.jetbrains.kotlinx.jupyter.messaging.ProtocolKt$shellMessagesHandler$2$res$1.invoke(protocol.kt:320)",
      "org.jetbrains.kotlinx.jupyter.JupyterExecutorImpl$runExecution$execThread$1.invoke(execution.kt:33)",
      "org.jetbrains.kotlinx.jupyter.JupyterExecutorImpl$runExecution$execThread$1.invoke(execution.kt:31)",
      "kotlin.concurrent.ThreadsKt$thread$thread$1.run(Thread.kt:30)"
    ],
    "additionalInfo": {
      "lineStart": 4,
      "colStart": 64,
      "lineEnd": 4,
      "colEnd": 75,
      "message": "Type mismatch: inferred type is geomPoint but Feature was expected",
      "path": "Line_69.jupyter-kts"
    }
  }
}

[alshan]

As geomPoint does of course extend Feature, the failure

Type mismatch: inferred type is geomPoint but Feature was expected

was likely caused by class loading conflict I reported here: #143

As a workaround: any usage of Lets-Plot before any usage of Krangl API will secure loading of Lets-Plot classes from correct jars. I usually just insert LetsPlot.getInfo() just after %use lets-plot. For example: https://nbviewer.org/github/JetBrains/lets-plot-kotlin/blob/master/docs/examples/jupyter-notebooks/geom_violin.ipynb

[muthenberg]

If I change to:

%use krangl(0.18.4)
%use lets-plot
LetsPlot.getInfo()

var sleepDataExt = sleepData.addColumn("rem_proportion"){it["sleep_rem"]/it["sleep_total"]}
sleepDataExt.letsPlot {x="sleep_total"; y="rem_proportion" } + geomPoint()

the error unfortunately still persists.

I also tried to load lets plot before krangl:

%use lets-plot
LetsPlot.getInfo()
%use krangl(0.18.4)

var sleepDataExt = sleepData.addColumn("rem_proportion"){it["sleep_rem"]/it["sleep_total"]}
sleepDataExt.letsPlot {x="sleep_total"; y="rem_proportion" } + geomPoint()

This doesn't solve the problem either. :(

[alshan]

Which Lets-Plot version does LetsPlot.getInfo() report? I believe that krangl v0.18.4 has already switched to the latest Lets-Plot Kotlin API v4.0.0.

If LetsPlot.getInfo() reports an older version then you need to tell Kotlin kernel to use the latest one. There are two options:

• Use the %useLatestDescriptors line magic.
• Provide the required version manually: %use lets-plot(api=4.0.0, lib=2.4.0, js=2.4.0)

Does this help?

[muthenberg]

Ok. Some of that advice seems to have fixed it. At first I still encountered the problem and needed to reset the kernel. After that it worked. Thank you.