# xarray.core.accessor_str.StringAccessor.islower

#### StringAccessor.islower()[[source]](https://github.com/pydata/xarray/blob/main/xarray/core/accessor_str.py#L961-L984)

Check whether all characters in each string are lowercase.

* **Returns:**
  **islower** ([array](https://numpy.org/doc/stable/glossary.html#term-array) of [`bool`](https://docs.python.org/3/builtins/functions.html#bool)) – Array of boolean values with the same shape as the original array indicating whether all characters of each
  element of the string array are lowercase (True) or not (False).

### Examples

<div class="try_examples_button_container"><button class="try_examples_button" onclick="window.tryExamplesShowIframe('948b8a8c-a8f2-4ce0-a941-1450a51d0426','e8bf74fd-b648-4cf6-b57a-85fe1319b00c','6de7ff24-7cb9-4a8e-a0db-7a7befdfd20b','../lite/tree/../notebooks/index.html?path=9bfbf0fe_b121_47f8_90c9_470eeecccdd1.ipynb','None')">Try it in your browser!</button></div>
```pycon
>>> da = xr.DataArray(["temperature", "HUMIDITY", "pREciPiTaTioN"], dims="x")
>>> da
<xarray.DataArray (x: 3)> Size: 156B
array(['temperature', 'HUMIDITY', 'pREciPiTaTioN'], dtype='<U13')
Dimensions without coordinates: x
>>> islower = da.str.islower()
>>> islower
<xarray.DataArray (x: 3)> Size: 3B
array([ True, False, False])
Dimensions without coordinates: x
```

<div id="6de7ff24-7cb9-4a8e-a0db-7a7befdfd20b" class="try_examples_outer_iframe  hidden"><div class="try_examples_button_container"><button class="try_examples_button" onclick="window.tryExamplesHideIframe('948b8a8c-a8f2-4ce0-a941-1450a51d0426','6de7ff24-7cb9-4a8e-a0db-7a7befdfd20b')">Go Back</button><button class="try_examples_button" onclick="window.openInNewTab('948b8a8c-a8f2-4ce0-a941-1450a51d0426','6de7ff24-7cb9-4a8e-a0db-7a7befdfd20b')">Open In Tab</button></div><div id="e8bf74fd-b648-4cf6-b57a-85fe1319b00c" class="jupyterlite_sphinx_iframe_container"></div></div><script>document.addEventListener("DOMContentLoaded", function() {window.loadTryExamplesConfig("../try_examples.json");});</script>