{ "cells": [ { "cell_type": "markdown", "metadata": { "editable": true, "slideshow": { "slide_type": "" }, "tags": [] }, "source": [ "## GRIB: selection using metadata" ] }, { "attachments": {}, "cell_type": "raw", "metadata": { "editable": true, "raw_mimetype": "text/restructuredtext", "slideshow": { "slide_type": "" }, "tags": [] }, "source": [ "We :ref:`read ` a GRIB file containing 18 messages. First we ensure the example file is available." ] }, { "cell_type": "code", "execution_count": 1, "metadata": { "editable": true, "slideshow": { "slide_type": "" }, "tags": [] }, "outputs": [], "source": [ "import earthkit.data as ekd\n", "ekd.download_example_file(\"tuv_pl.grib\")" ] }, { "cell_type": "code", "execution_count": 2, "metadata": {}, "outputs": [], "source": [ "ds = ekd.from_source(\"file\", \"tuv_pl.grib\")" ] }, { "cell_type": "code", "execution_count": 3, "metadata": {}, "outputs": [ { "data": { "text/plain": [ "18" ] }, "execution_count": 3, "metadata": {}, "output_type": "execute_result" } ], "source": [ "len(ds)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "### Using sel" ] }, { "cell_type": "raw", "metadata": { "editable": true, "raw_mimetype": "text/restructuredtext", "slideshow": { "slide_type": "" }, "tags": [] }, "source": [ "Calling :py:meth:`~data.readers.grib.index.GribFieldList.sel` provides a \"view\":" ] }, { "cell_type": "code", "execution_count": 4, "metadata": { "editable": true, "slideshow": { "slide_type": "" }, "tags": [] }, "outputs": [ { "data": { "text/html": [ "
\n", "\n", "\n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", "
centreshortNametypeOfLevelleveldataDatedataTimestepRangedataTypenumbergridType
0ecmftisobaricInhPa5002018080112000an0regular_ll
1ecmfuisobaricInhPa5002018080112000an0regular_ll
2ecmfvisobaricInhPa5002018080112000an0regular_ll
\n", "
" ], "text/plain": [ " centre shortName typeOfLevel level dataDate dataTime stepRange \\\n", "0 ecmf t isobaricInhPa 500 20180801 1200 0 \n", "1 ecmf u isobaricInhPa 500 20180801 1200 0 \n", "2 ecmf v isobaricInhPa 500 20180801 1200 0 \n", "\n", " dataType number gridType \n", "0 an 0 regular_ll \n", "1 an 0 regular_ll \n", "2 an 0 regular_ll " ] }, "execution_count": 4, "metadata": {}, "output_type": "execute_result" } ], "source": [ "a = ds.sel(level=500)\n", "a.ls()" ] }, { "cell_type": "code", "execution_count": 5, "metadata": {}, "outputs": [ { "data": { "text/plain": [ "earthkit.data.readers.grib.index.GribMaskFieldList" ] }, "execution_count": 5, "metadata": {}, "output_type": "execute_result" } ], "source": [ "type(a)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "We can use a dict instead of keyword arguments:" ] }, { "cell_type": "code", "execution_count": 6, "metadata": {}, "outputs": [ { "data": { "text/html": [ "
\n", "\n", "\n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", "
centreshortNametypeOfLevelleveldataDatedataTimestepRangedataTypenumbergridType
0ecmfvisobaricInhPa5002018080112000an0regular_ll
\n", "
" ], "text/plain": [ " centre shortName typeOfLevel level dataDate dataTime stepRange \\\n", "0 ecmf v isobaricInhPa 500 20180801 1200 0 \n", "\n", " dataType number gridType \n", "0 an 0 regular_ll " ] }, "execution_count": 6, "metadata": {}, "output_type": "execute_result" } ], "source": [ "a = ds.sel({\"level\": 500, \"shortName\": \"v\"})\n", "a.ls()" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "Lists are accepted:" ] }, { "cell_type": "code", "execution_count": 7, "metadata": {}, "outputs": [ { "data": { "text/html": [ "
\n", "\n", "\n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", "
centreshortNametypeOfLevelleveldataDatedataTimestepRangedataTypenumbergridType
0ecmftisobaricInhPa8502018080112000an0regular_ll
1ecmfuisobaricInhPa8502018080112000an0regular_ll
2ecmfvisobaricInhPa8502018080112000an0regular_ll
3ecmftisobaricInhPa5002018080112000an0regular_ll
4ecmfuisobaricInhPa5002018080112000an0regular_ll
5ecmfvisobaricInhPa5002018080112000an0regular_ll
\n", "
" ], "text/plain": [ " centre shortName typeOfLevel level dataDate dataTime stepRange \\\n", "0 ecmf t isobaricInhPa 850 20180801 1200 0 \n", "1 ecmf u isobaricInhPa 850 20180801 1200 0 \n", "2 ecmf v isobaricInhPa 850 20180801 1200 0 \n", "3 ecmf t isobaricInhPa 500 20180801 1200 0 \n", "4 ecmf u isobaricInhPa 500 20180801 1200 0 \n", "5 ecmf v isobaricInhPa 500 20180801 1200 0 \n", "\n", " dataType number gridType \n", "0 an 0 regular_ll \n", "1 an 0 regular_ll \n", "2 an 0 regular_ll \n", "3 an 0 regular_ll \n", "4 an 0 regular_ll \n", "5 an 0 regular_ll " ] }, "execution_count": 7, "metadata": {}, "output_type": "execute_result" } ], "source": [ "a = ds.sel(level=[500, 850])\n", "a.ls()" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "Slices can define closed intervals, so they are treated as inclusive of both the start and stop values, unlike normal Python indexing:" ] }, { "cell_type": "code", "execution_count": 8, "metadata": {}, "outputs": [ { "data": { "text/html": [ "
\n", "\n", "\n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", "
centreshortNametypeOfLevelleveldataDatedataTimestepRangedataTypenumbergridType
0ecmftisobaricInhPa8502018080112000an0regular_ll
1ecmftisobaricInhPa7002018080112000an0regular_ll
2ecmftisobaricInhPa5002018080112000an0regular_ll
\n", "
" ], "text/plain": [ " centre shortName typeOfLevel level dataDate dataTime stepRange \\\n", "0 ecmf t isobaricInhPa 850 20180801 1200 0 \n", "1 ecmf t isobaricInhPa 700 20180801 1200 0 \n", "2 ecmf t isobaricInhPa 500 20180801 1200 0 \n", "\n", " dataType number gridType \n", "0 an 0 regular_ll \n", "1 an 0 regular_ll \n", "2 an 0 regular_ll " ] }, "execution_count": 8, "metadata": {}, "output_type": "execute_result" } ], "source": [ "a = ds.sel(param=\"t\", level=slice(500, 850))\n", "a.ls()" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "### Using isel" ] }, { "cell_type": "raw", "metadata": { "editable": true, "raw_mimetype": "text/restructuredtext", "slideshow": { "slide_type": "" }, "tags": [] }, "source": [ ":py:meth:`~data.readers.grib.index.GribFieldList.isel` works similarly to :py:meth:`~data.readers.grib.index.GribFieldList.sel` but takes indices instead of values. Please note that the index values are sorted for :py:meth:`~data.readers.grib.index.GribFieldList.sel`." ] }, { "cell_type": "code", "execution_count": 9, "metadata": { "editable": true, "slideshow": { "slide_type": "" }, "tags": [] }, "outputs": [ { "data": { "text/html": [ "
\n", "\n", "\n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", "
centreshortNametypeOfLevelleveldataDatedataTimestepRangedataTypenumbergridType
0ecmftisobaricInhPa3002018080112000an0regular_ll
1ecmfuisobaricInhPa3002018080112000an0regular_ll
2ecmfvisobaricInhPa3002018080112000an0regular_ll
\n", "
" ], "text/plain": [ " centre shortName typeOfLevel level dataDate dataTime stepRange \\\n", "0 ecmf t isobaricInhPa 300 20180801 1200 0 \n", "1 ecmf u isobaricInhPa 300 20180801 1200 0 \n", "2 ecmf v isobaricInhPa 300 20180801 1200 0 \n", "\n", " dataType number gridType \n", "0 an 0 regular_ll \n", "1 an 0 regular_ll \n", "2 an 0 regular_ll " ] }, "execution_count": 9, "metadata": {}, "output_type": "execute_result" } ], "source": [ "a = ds.isel(level=0)\n", "a.ls()" ] }, { "cell_type": "code", "execution_count": 10, "metadata": {}, "outputs": [ { "data": { "text/html": [ "
\n", "\n", "\n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", "
centreshortNametypeOfLevelleveldataDatedataTimestepRangedataTypenumbergridType
0ecmfuisobaricInhPa5002018080112000an0regular_ll
\n", "
" ], "text/plain": [ " centre shortName typeOfLevel level dataDate dataTime stepRange \\\n", "0 ecmf u isobaricInhPa 500 20180801 1200 0 \n", "\n", " dataType number gridType \n", "0 an 0 regular_ll " ] }, "execution_count": 10, "metadata": {}, "output_type": "execute_result" } ], "source": [ "a = ds.isel({\"level\": 2, \"shortName\": 1})\n", "a.ls()" ] }, { "cell_type": "code", "execution_count": 11, "metadata": {}, "outputs": [ { "data": { "text/html": [ "
\n", "\n", "\n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", "
centreshortNametypeOfLevelleveldataDatedataTimestepRangedataTypenumbergridType
0ecmftisobaricInhPa7002018080112000an0regular_ll
1ecmftisobaricInhPa5002018080112000an0regular_ll
\n", "
" ], "text/plain": [ " centre shortName typeOfLevel level dataDate dataTime stepRange \\\n", "0 ecmf t isobaricInhPa 700 20180801 1200 0 \n", "1 ecmf t isobaricInhPa 500 20180801 1200 0 \n", "\n", " dataType number gridType \n", "0 an 0 regular_ll \n", "1 an 0 regular_ll " ] }, "execution_count": 11, "metadata": {}, "output_type": "execute_result" } ], "source": [ "a = ds.isel(level=[2,3], param=0)\n", "a.ls()" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "Slices are used as in normal Python indexing: " ] }, { "cell_type": "code", "execution_count": 12, "metadata": {}, "outputs": [ { "data": { "text/html": [ "
\n", "\n", "\n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", "
centreshortNametypeOfLevelleveldataDatedataTimestepRangedataTypenumbergridType
0ecmftisobaricInhPa8502018080112000an0regular_ll
1ecmftisobaricInhPa7002018080112000an0regular_ll
2ecmftisobaricInhPa5002018080112000an0regular_ll
\n", "
" ], "text/plain": [ " centre shortName typeOfLevel level dataDate dataTime stepRange \\\n", "0 ecmf t isobaricInhPa 850 20180801 1200 0 \n", "1 ecmf t isobaricInhPa 700 20180801 1200 0 \n", "2 ecmf t isobaricInhPa 500 20180801 1200 0 \n", "\n", " dataType number gridType \n", "0 an 0 regular_ll \n", "1 an 0 regular_ll \n", "2 an 0 regular_ll " ] }, "execution_count": 12, "metadata": {}, "output_type": "execute_result" } ], "source": [ "a = ds.isel(level=slice(2,5), param=0)\n", "a.ls()" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "### Using order_by" ] }, { "cell_type": "raw", "metadata": { "editable": true, "raw_mimetype": "text/restructuredtext", "slideshow": { "slide_type": "" }, "tags": [] }, "source": [ "Calling :py:meth:`~data.readers.grib.index.GribFieldList.order_by` provides a \"view\":" ] }, { "cell_type": "code", "execution_count": 13, "metadata": { "editable": true, "slideshow": { "slide_type": "" }, "tags": [] }, "outputs": [ { "data": { "text/plain": [ "earthkit.data.readers.grib.index.GribMaskFieldList" ] }, "execution_count": 13, "metadata": {}, "output_type": "execute_result" } ], "source": [ "b = a.order_by()\n", "type(b)" ] }, { "cell_type": "code", "execution_count": 14, "metadata": {}, "outputs": [ { "data": { "text/html": [ "
\n", "\n", "\n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", "
centreshortNametypeOfLevelleveldataDatedataTimestepRangedataTypenumbergridType
0ecmftisobaricInhPa8502018080112000an0regular_ll
1ecmftisobaricInhPa7002018080112000an0regular_ll
2ecmftisobaricInhPa5002018080112000an0regular_ll
\n", "
" ], "text/plain": [ " centre shortName typeOfLevel level dataDate dataTime stepRange \\\n", "0 ecmf t isobaricInhPa 850 20180801 1200 0 \n", "1 ecmf t isobaricInhPa 700 20180801 1200 0 \n", "2 ecmf t isobaricInhPa 500 20180801 1200 0 \n", "\n", " dataType number gridType \n", "0 an 0 regular_ll \n", "1 an 0 regular_ll \n", "2 an 0 regular_ll " ] }, "execution_count": 14, "metadata": {}, "output_type": "execute_result" } ], "source": [ "b.ls()" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "The sorting keys can be specified as a list:" ] }, { "cell_type": "code", "execution_count": 15, "metadata": {}, "outputs": [ { "data": { "text/html": [ "
\n", "\n", "\n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", "
centreshortNametypeOfLevelleveldataDatedataTimestepRangedataTypenumbergridType
0ecmftisobaricInhPa8502018080112000an0regular_ll
1ecmftisobaricInhPa7002018080112000an0regular_ll
2ecmftisobaricInhPa5002018080112000an0regular_ll
\n", "
" ], "text/plain": [ " centre shortName typeOfLevel level dataDate dataTime stepRange \\\n", "0 ecmf t isobaricInhPa 850 20180801 1200 0 \n", "1 ecmf t isobaricInhPa 700 20180801 1200 0 \n", "2 ecmf t isobaricInhPa 500 20180801 1200 0 \n", "\n", " dataType number gridType \n", "0 an 0 regular_ll \n", "1 an 0 regular_ll \n", "2 an 0 regular_ll " ] }, "execution_count": 15, "metadata": {}, "output_type": "execute_result" } ], "source": [ "b = a.order_by([\"shortName\"])\n", "b.ls()" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "We can prescribe the actual order within a key. It only works when all the possible values are specified:" ] }, { "cell_type": "code", "execution_count": 16, "metadata": {}, "outputs": [ { "data": { "text/html": [ "
\n", "\n", "\n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", "
centreshortNametypeOfLevelleveldataDatedataTimestepRangedataTypenumbergridType
0ecmftisobaricInhPa8502018080112000an0regular_ll
1ecmftisobaricInhPa7002018080112000an0regular_ll
2ecmftisobaricInhPa5002018080112000an0regular_ll
\n", "
" ], "text/plain": [ " centre shortName typeOfLevel level dataDate dataTime stepRange \\\n", "0 ecmf t isobaricInhPa 850 20180801 1200 0 \n", "1 ecmf t isobaricInhPa 700 20180801 1200 0 \n", "2 ecmf t isobaricInhPa 500 20180801 1200 0 \n", "\n", " dataType number gridType \n", "0 an 0 regular_ll \n", "1 an 0 regular_ll \n", "2 an 0 regular_ll " ] }, "execution_count": 16, "metadata": {}, "output_type": "execute_result" } ], "source": [ "a = a.order_by(shortName=[\"v\", \"t\", \"u\"])\n", "a.ls()" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "### Combining sel and order_by" ] }, { "cell_type": "code", "execution_count": 17, "metadata": {}, "outputs": [ { "data": { "text/html": [ "
\n", "\n", "\n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", " \n", "
centreshortNametypeOfLevelleveldataDatedataTimestepRangedataTypenumbergridType
0ecmftisobaricInhPa8502018080112000an0regular_ll
1ecmftisobaricInhPa5002018080112000an0regular_ll
2ecmfuisobaricInhPa8502018080112000an0regular_ll
3ecmfuisobaricInhPa5002018080112000an0regular_ll
4ecmfvisobaricInhPa8502018080112000an0regular_ll
5ecmfvisobaricInhPa5002018080112000an0regular_ll
\n", "
" ], "text/plain": [ " centre shortName typeOfLevel level dataDate dataTime stepRange \\\n", "0 ecmf t isobaricInhPa 850 20180801 1200 0 \n", "1 ecmf t isobaricInhPa 500 20180801 1200 0 \n", "2 ecmf u isobaricInhPa 850 20180801 1200 0 \n", "3 ecmf u isobaricInhPa 500 20180801 1200 0 \n", "4 ecmf v isobaricInhPa 850 20180801 1200 0 \n", "5 ecmf v isobaricInhPa 500 20180801 1200 0 \n", "\n", " dataType number gridType \n", "0 an 0 regular_ll \n", "1 an 0 regular_ll \n", "2 an 0 regular_ll \n", "3 an 0 regular_ll \n", "4 an 0 regular_ll \n", "5 an 0 regular_ll " ] }, "execution_count": 17, "metadata": {}, "output_type": "execute_result" } ], "source": [ "a = ds.sel(level=[500, 850]).order_by([\"shortName\"])\n", "a.ls()" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "### Using indices" ] }, { "cell_type": "raw", "metadata": { "editable": true, "raw_mimetype": "text/restructuredtext", "slideshow": { "slide_type": "" }, "tags": [] }, "source": [ "To get the unique values for predefined set of metadata keys (the MARS ecCodes keys) we can call :py:meth:`~data.readers.grib.index.GribFieldList.indices`. By default it returns all the keys having valid values:" ] }, { "cell_type": "code", "execution_count": 18, "metadata": { "editable": true, "slideshow": { "slide_type": "" }, "tags": [] }, "outputs": [ { "data": { "text/plain": [ "{'class': ['od'],\n", " 'stream': ['oper'],\n", " 'levtype': ['pl'],\n", " 'type': ['an'],\n", " 'expver': ['0001'],\n", " 'date': [20180801],\n", " 'time': [1200],\n", " 'domain': ['g'],\n", " 'number': [0],\n", " 'levelist': [300, 400, 500, 700, 850, 1000],\n", " 'param': ['t', 'u', 'v'],\n", " 'level': [300, 400, 500, 700, 850, 1000],\n", " 'shortName': ['t', 'u', 'v']}" ] }, "execution_count": 18, "metadata": {}, "output_type": "execute_result" } ], "source": [ "ds.indices()" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "We can use the *squeeze* option to see only the keys having more than one values:" ] }, { "cell_type": "code", "execution_count": 19, "metadata": {}, "outputs": [ { "data": { "text/plain": [ "{'levelist': [300, 400, 500, 700, 850, 1000],\n", " 'param': ['t', 'u', 'v'],\n", " 'level': [300, 400, 500, 700, 850, 1000],\n", " 'shortName': ['t', 'u', 'v']}" ] }, "execution_count": 19, "metadata": {}, "output_type": "execute_result" } ], "source": [ "ds.indices(squeeze=True)" ] }, { "cell_type": "raw", "metadata": { "editable": true, "raw_mimetype": "text/restructuredtext", "slideshow": { "slide_type": "" }, "tags": [] }, "source": [ "We can get the unique values for a given key with :py:meth:`~data.readers.grib.index.GribFieldList.index` :" ] }, { "cell_type": "code", "execution_count": 20, "metadata": { "editable": true, "slideshow": { "slide_type": "" }, "tags": [] }, "outputs": [ { "data": { "text/plain": [ "['t', 'u', 'v']" ] }, "execution_count": 20, "metadata": {}, "output_type": "execute_result" } ], "source": [ "ds.index(\"param\")" ] }, { "cell_type": "code", "execution_count": 21, "metadata": {}, "outputs": [ { "data": { "text/plain": [ "[20180801]" ] }, "execution_count": 21, "metadata": {}, "output_type": "execute_result" } ], "source": [ "ds.index(\"date\")" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "Aliases can be used. E.g. instead of levelist we can use level:" ] }, { "cell_type": "code", "execution_count": 22, "metadata": {}, "outputs": [ { "data": { "text/plain": [ "[300, 400, 500, 700, 850, 1000]" ] }, "execution_count": 22, "metadata": {}, "output_type": "execute_result" } ], "source": [ "ds.index(\"level\")" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "Count the number of fields for each available level:" ] }, { "cell_type": "code", "execution_count": 23, "metadata": {}, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "level=300 len=3\n", "level=400 len=3\n", "level=500 len=3\n", "level=700 len=3\n", "level=850 len=3\n", "level=1000 len=3\n" ] } ], "source": [ "for level in ds.index(\"level\"):\n", " print(f\"level={level} len={len(ds.sel(level=level))}\")" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [] } ], "metadata": { "kernelspec": { "display_name": "Python 3 (ipykernel)", "language": "python", "name": "python3" }, "language_info": { "codemirror_mode": { "name": "ipython", "version": 3 }, "file_extension": ".py", "mimetype": "text/x-python", "name": "python", "nbconvert_exporter": "python", "pygments_lexer": "ipython3", "version": "3.10.13" } }, "nbformat": 4, "nbformat_minor": 4 }