python-data/exercises/ex03a_xr_groupby.ipynb

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   "source": [
    "# Exercise 3a: Grouping"
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    "## Aim: Work with data which has been grouped."
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   "source": [
    "Find the teaching resources here: https://tutorial.xarray.dev/fundamentals/03.2_groupby_with_xarray.html"
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    "### Issues Covered:\n",
    "- Grouping data with `.groupby()`\n",
    "- Finding the mean of grouped data."
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    "## GroupBy processing"
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   "source": [
    "Our ocean model dataset has no time dimension, so for this exercise we are going to use the NOAA ERSSST dataset from the tutorial. Load it using the command below."
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   "source": [
    "import xarray as xr\n",
    "ds = xr.tutorial.load_dataset(\"ersstv5\")"
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    "Have a quick explore of the dataset and see what it contains."
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   "source": [
    "Q1. First, lets group our dataset by year."
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    "Q2. Lets take the mean of each group, to give the annual mean."
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    "Q3. To see what we've done, lets plot the mean for the year 1960."
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    "Q4. Next, lets plot an annual mean time seties for the point in the Atlantic ocean latitude=-50.625, longitude=0."
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