How to use in Python

Using ncplot is very easy. It let’s you plot the contents of a NetCDF automatically. To plot a file in Python, preferably a Jupyter notebook, do the following:

from ncplot import view
view("https://psl.noaa.gov/thredds/dodsC/Datasets/COBE2/sst.mon.ltm.1981-2010.nc")

/home/robert/anaconda3/envs/nc/lib/python3.6/site-packages/xarray/coding/times.py:427: SerializationWarning: Unable to decode time axis into full numpy.datetime64 objects, continuing using cftime.datetime objects instead, reason: dates out of range
  dtype = _decode_cf_datetime_dtype(data, units, calendar, self.use_cftime)
/home/robert/anaconda3/envs/nc/lib/python3.6/site-packages/numpy/core/_asarray.py:83: SerializationWarning: Unable to decode time axis into full numpy.datetime64 objects, continuing using cftime.datetime objects instead, reason: dates out of range
  return array(a, dtype, copy=False, order=order)
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
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WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
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If you only want to plot a specific variable, you can do the following:

If you want to plot a list of variables, do the following:

view("https://psl.noaa.gov/thredds/dodsC/Datasets/COBE2/sst.mon.ltm.1981-2010.nc", "sst")

/home/robert/anaconda3/envs/nc/lib/python3.6/site-packages/xarray/coding/times.py:427: SerializationWarning: Unable to decode time axis into full numpy.datetime64 objects, continuing using cftime.datetime objects instead, reason: dates out of range
  dtype = _decode_cf_datetime_dtype(data, units, calendar, self.use_cftime)
/home/robert/anaconda3/envs/nc/lib/python3.6/site-packages/numpy/core/_asarray.py:83: SerializationWarning: Unable to decode time axis into full numpy.datetime64 objects, continuing using cftime.datetime objects instead, reason: dates out of range
  return array(a, dtype, copy=False, order=order)
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace

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There are built in ways to access xarray objects. To read a file in just do the following:

import xarray as xr
import ncplot.xarray
ds = xr.open_dataset("https://psl.noaa.gov/thredds/dodsC/Datasets/COBE2/sst.mon.ltm.1981-2010.nc")
ds.ncplot.view()

/home/robert/anaconda3/envs/nc/lib/python3.6/site-packages/xarray/coding/times.py:427: SerializationWarning: Unable to decode time axis into full numpy.datetime64 objects, continuing using cftime.datetime objects instead, reason: dates out of range
  dtype = _decode_cf_datetime_dtype(data, units, calendar, self.use_cftime)
/home/robert/anaconda3/envs/nc/lib/python3.6/site-packages/numpy/core/_asarray.py:83: SerializationWarning: Unable to decode time axis into full numpy.datetime64 objects, continuing using cftime.datetime objects instead, reason: dates out of range
  return array(a, dtype, copy=False, order=order)
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace
WARNING:param.ParameterizedMetaclass: Use method 'params' via param namespace

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How to use as a command line tool

ncplot operates as a command line tool, letting you view the contents of a NetCDF file on a website. This feature only works in development version right now. All you need to do is provide the file you want to look at:

$ ncplot https://psl.noaa.gov/thredds/dodsC/Datasets/COBE2/sst.mon.ltm.1981-2010.nc