# Undefined symbol: cblas\_dgemm

**URL:** <https://discuss.hail.is/t/undefined-symbol-cblas-dgemm/1488>\
**Category:** Hail Query & hailctl\
**Created:** [June 24, 2020, 7:24pm UTC](https://discuss.hail.is/t/undefined-symbol-cblas-dgemm/1488 "2020-06-24T19:24:09Z")\
**Posts on this page:** 1\
**Showing post:** 2

<div class="post-metadata">

**Author:** ![danking](https://yyz2.discourse-cdn.com/flex036/user_avatar/discuss.hail.is/danking/32/43_2.png) [@danking](https://discuss.hail.is/u/danking)\
**Post date:** [June 24, 2020, 7:25pm UTC](https://discuss.hail.is/t/undefined-symbol-cblas-dgemm/1488/2 "2020-06-24T19:25:49Z")

</div>

I’m sorry to hear you ran into this problem!

This either means you have incompatible BLAS libraries installed or Hail cannot find your BLAS libraries. Try setting the executor class path to explicitly reference the libraries. If you’re using `spark-submit`, try this:

```bash
--conf spark.executor.extraClassPath="/path/to/libblas.so:/path/to/liblapack.so"

```

You can also set configuration parameters in:

```auto
hl.init(spark_conf={
    "spark.executor.extraClassPath": "/path/to/libblas.so:/path/to/liblapack.so"})

```

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_[View the full topic](https://discuss.hail.is/t/undefined-symbol-cblas-dgemm/1488)._