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This leverages all the goodness of ValueHelpers, including obeying local formatting conventions. To avoid breaking old skins, the VH versions have been given new names.
696 lines
21 KiB
Markdown
696 lines
21 KiB
Markdown
# Appendix
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## Aggregation types {#aggregation_types}
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<table>
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<caption>Aggregation types</caption>
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<tbody>
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<tr class="first_row">
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<td>Aggregation type</td>
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<td>Meaning</td>
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</tr>
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<tr>
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<td class="first_col code">avg</td>
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<td>The average value in the aggregation period.</td>
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</tr>
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<tr>
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<td class="first_col code">avg_ge(val)</td>
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<td>The number of days where the average value is greater than or equal to <em>val</em>. Aggregation
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period must be one day or longer. The argument <span class="code">val</span> is a
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<a href="#ValueTuple"><span class="code">ValueTuple</span></a>.
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</td>
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</tr>
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<tr>
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<td class="first_col code">avg_le(val)</td>
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<td>The number of days where the average value is less than or equal to <em>val</em>. Aggregation period
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must be one day or longer. The argument <span class="code">val</span> is a
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<a href="#ValueTuple"><span class="code">ValueTuple</span></a>.
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</td>
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</tr>
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<tr>
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<td class="first_col code">count</td>
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<td>The number of non-null values in the aggregation period.
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</td>
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</tr>
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<tr>
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<td class="first_col code">diff</td>
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<td>The difference between the last and first value in the aggregation period.
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</td>
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</tr>
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<tr>
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<td class="first_col code">exists</td>
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<td>Returns <span class="code">True</span> if the observation type exists in the database.</td>
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</tr>
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<tr>
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<td class="first_col code">first</td>
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<td>The first non-null value in the aggregation period.</td>
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</tr>
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<tr>
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<td class="first_col code">firsttime</td>
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<td>The time of the first non-null value in the aggregation period.
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</td>
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</tr>
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<tr>
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<td class="first_col code">gustdir</td>
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<td>The direction of the max gust in the aggregation period.
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</td>
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</tr>
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<tr>
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<td class="first_col code">has_data</td>
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<td>Returns <span class="code">True</span> if the observation type exists in the database and is
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non-null.
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</td>
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</tr>
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<tr>
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<td class="first_col code">last</td>
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<td>The last non-null value in the aggregation period.</td>
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</tr>
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<tr>
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<td class="first_col code">lasttime</td>
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<td>The time of the last non-null value in the aggregation period.
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</td>
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</tr>
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<tr>
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<td class="first_col code">max</td>
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<td>The maximum value in the aggregation period.</td>
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</tr>
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<tr>
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<td class="first_col code">maxmin</td>
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<td>The maximum daily minimum in the aggregation period. Aggregation period must be one day or longer.
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</td>
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</tr>
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<tr>
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<td class="first_col code">maxmintime</td>
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<td>The time of the maximum daily minimum.</td>
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</tr>
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<tr>
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<td class="first_col code">maxsum</td>
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<td>The maximum daily sum in the aggregation period. Aggregation period must be one day or longer.
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</td>
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</tr>
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<tr>
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<td class="first_col code">maxsumtime</td>
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<td>The time of the maximum daily sum.</td>
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</tr>
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<tr>
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<td class="first_col code">maxtime</td>
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<td>The time of the maximum value.</td>
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</tr>
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<tr>
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<td class="first_col code">max_ge(val)</td>
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<td>The number of days where the maximum value is greater than or equal to <em>val</em>. Aggregation
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period must be one day or longer. The argument <span class="code">val</span> is a
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<a href="#ValueTuple"><span class="code">ValueTuple</span></a>.
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</td>
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</tr>
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<tr>
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<td class="first_col code">max_le(val)</td>
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<td>The number of days where the maximum value is less than or equal to <em>val</em>. Aggregation period
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must be one day or longer. The argument <span class="code">val</span> is a
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<a href="#ValueTuple"><span class="code">ValueTuple</span></a>.
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</td>
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</tr>
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<tr>
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<td class="first_col code">meanmax</td>
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<td>The average daily maximum in the aggregation period. Aggregation period must be one day or longer.
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</td>
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</tr>
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<tr>
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<td class="first_col code">meanmin</td>
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<td>The average daily minimum in the aggregation period. Aggregation period must be one day or longer.
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</td>
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</tr>
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<tr>
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<td class="first_col code">min</td>
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<td>The minimum value in the aggregation period.</td>
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</tr>
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<tr>
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<td class="first_col code">minmax</td>
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<td>The minimum daily maximum in the aggregation period. Aggregation period must be one day or longer.
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</td>
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</tr>
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<tr>
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<td class="first_col code">minmaxtime</td>
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<td>The time of the minimum daily maximum.</td>
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</tr>
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<tr>
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<td class="first_col code">minsum</td>
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<td>The minimum daily sum in the aggregation period. Aggregation period must be one day or longer.
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</td>
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</tr>
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<tr>
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<td class="first_col code">minsumtime</td>
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<td>The time of the minimum daily sum.</td>
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</tr>
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<tr>
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<td class="first_col code">mintime</td>
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<td>The time of the minimum value.</td>
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</tr>
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<tr>
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<td class="first_col code">min_ge(val)</td>
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<td>The number of days where the minimum value is greater than or equal to <em>val</em>. Aggregation
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period must be one day or longer. The argument <span class="code">val</span> is a
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<a href="#ValueTuple"><span class="code">ValueTuple</span></a>.
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</td>
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</tr>
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<tr>
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<td class="first_col code">min_le(val)</td>
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<td>The number of days where the minimum value is less than or equal to <em>val</em>. Aggregation period
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must be one day or longer. The argument <span class="code">val</span> is a
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<a href="#ValueTuple"><span class="code">ValueTuple</span></a>.
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</td>
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</tr>
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<tr>
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<td class="first_col code">not_null</td>
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<td>
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Returns truthy if any value over the aggregation period is non-null.
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</td>
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</tr>
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<tr>
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<td class="first_col code">rms</td>
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<td>The root mean square value in the aggregation period.
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</td>
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</tr>
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<tr>
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<td class="first_col code">sum</td>
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<td>The sum of values in the aggregation period.</td>
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</tr>
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<tr>
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<td class="first_col code">sum_ge(val)</td>
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<td>The number of days where the sum of value is greater than or equal to <em>val</em>. Aggregation
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period must be one day or longer. The argument <span class="code">val</span> is a
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<a href="#ValueTuple"><span class="code">ValueTuple</span></a>.
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</td>
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</tr>
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<tr>
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<td class="first_col code">sum_le(val)</td>
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<td>The number of days where the sum of value is less than or equal to <em>val</em>. Aggregation period
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must be one day or longer. The argument <span class="code">val</span> is a
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<a href="#ValueTuple"><span class="code">ValueTuple</span></a>.
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</td>
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</tr>
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<tr>
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<td class="first_col code">tderiv</td>
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<td>
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The time derivative between the last and first value in the aggregation period. This is the
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difference in value divided by the difference in time.
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</td>
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</tr>
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<tr>
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<td class="first_col code">vecavg</td>
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<td>The vector average speed in the aggregation period.</td>
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</tr>
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<tr>
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<td class="first_col code">vecdir</td>
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<td>The vector averaged direction during the aggregation period.
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</td>
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</tr>
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</tbody>
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</table>
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## Units {#units}
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WeeWX offers three different *unit systems*:
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<table>
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<caption>The standard unit systems used within WeeWX</caption>
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<tr class="first_row">
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<td>Name</td>
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<td>Encoded value</td>
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<td>Note</td>
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</tr>
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<tr>
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<td class="first_col code">US</td>
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<td>0x01</td>
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<td>U.S. Customary</td>
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</tr>
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<tr>
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<td class="first_col code">METRICWX</td>
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<td>0x11</td>
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<td>Metric, with rain related measurements in <span class="code">mm</span> and speeds in <span
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class="code">m/s</span>
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</td>
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</tr>
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<tr>
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<td class="first_col code">METRIC</td>
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<td>0x10</td>
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<td>Metric, with rain related measurements in <span class="code">cm</span> and speeds in <span
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class="code">km/hr</span>
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</td>
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</tr>
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</table>
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The table below lists all the unit groups, their members, which units
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are options for the group, and what the defaults are for each standard
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unit system.
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<table>
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<caption>Unit groups, members and options</caption>
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<tbody class="code">
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<tr class="first_row">
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<td>Group</td>
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<td>Members</td>
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<td>Unit options</td>
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<td><span class="code">US</span></td>
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<td><span class="code">METRICWX</span></td>
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<td><span class="code">METRIC</span></td>
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</tr>
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<tr>
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<td class="first_col">group_altitude</td>
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<td>altitude<br/> cloudbase
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</td>
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<td>foot <br/> meter
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</td>
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<td>foot</td>
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<td>meter</td>
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<td>meter</td>
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</tr>
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<tr>
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<td class="first_col">group_amp</td>
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<td></td>
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<td>amp</td>
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<td>amp</td>
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<td>amp</td>
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<td>amp</td>
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</tr>
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<tr>
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<td class="first_col">group_angle</td>
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<td></td>
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<td>degree_angle<br/>radian</td>
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<td>degree_angle</td>
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<td>degree_angle</td>
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<td>degree_angle</td>
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</tr>
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<tr>
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<td class="first_col">group_boolean</td>
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<td></td>
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<td>boolean</td>
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<td>boolean</td>
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<td>boolean</td>
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<td>boolean</td>
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</tr>
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<tr>
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<td class="first_col">group_concentration</td>
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<td>no2<br/>pm1_0<br/>pm2_5<br/>pm10_0</td>
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<td>microgram_per_meter_cubed</td>
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<td>microgram_per_meter_cubed</td>
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<td>microgram_per_meter_cubed</td>
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<td>microgram_per_meter_cubed</td>
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</tr>
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<tr>
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<td class="first_col">group_count</td>
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<td>leafWet1<br/>leafWet2<br/>lightning_disturber_count<br/>lightning_noise_count<br/>lightning_strike_count<br/></td>
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<td>count</td>
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<td>count</td>
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<td>count</td>
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<td>count</td>
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</tr>
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<tr>
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<td class="first_col">group_data</td>
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<td></td>
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<td>byte<br/> bit</td>
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<td>byte</td>
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<td>byte</td>
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<td>byte</td>
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</tr>
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<tr>
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<td class="first_col">group_db</td>
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<td>noise</td>
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<td>dB</td>
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<td>dB</td>
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<td>dB</td>
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<td>dB</td>
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</tr>
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<tr>
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<td class="first_col">group_delta_time</td>
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<td>daySunshineDur<br/>rainDur<br/>sunshineDurDoc</td>
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<td>second<br/> minute<br/>hour<br/>day<br/></td>
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<td>second</td>
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<td>second</td>
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<td>second</td>
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</tr>
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<tr>
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<td class="first_col">group_degree_day</td>
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<td>cooldeg<br/> heatdeg<br/> growdeg
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</td>
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<td>degree_F_day<br/> degree_C_day</td>
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<td>degree_F_day</td>
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<td>degree_C_day</td>
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<td>degree_C_day</td>
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</tr>
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<tr>
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<td class="first_col">group_direction</td>
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<td>gustdir <br/> vecdir <br/> windDir <br/> windGustDir</td>
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<td>degree_compass</td>
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<td>degree_compass</td>
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<td>degree_compass</td>
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<td>degree_compass</td>
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</tr>
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<tr>
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<td class="first_col">group_distance</td>
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<td>windrun<br/>lightning_distance</td>
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<td>mile<br/>km</td>
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<td>mile</td>
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<td>km</td>
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<td>km</td>
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</tr>
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<tr>
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<td class="first_col">group_energy</td>
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<td></td>
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<td>kilowatt_hour<br/>mega_joule<br/>watt_hour<br/>watt_second</td>
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<td>watt_hour</td>
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<td>watt_hour</td>
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<td>watt_hour</td>
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</tr>
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<tr>
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<td class="first_col">group_energy2</td>
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<td></td>
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<td>kilowatt_hour<br/>watt_hour<br/>watt_second</td>
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<td>watt_second</td>
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<td>watt_second</td>
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<td>watt_second</td>
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</tr>
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<tr>
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<td class="first_col">group_fraction</td>
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<td>co<br/>co2<br/>nh3<br/>o3<br/>pb<br/>so2</td>
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<td>ppm</td>
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<td>ppm</td>
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<td>ppm</td>
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<td>ppm</td>
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</tr>
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<tr>
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<td class="first_col">group_frequency</td>
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<td></td>
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<td>hertz</td>
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<td>hertz</td>
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<td>hertz</td>
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<td>hertz</td>
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</tr>
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<tr>
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<td class="first_col">group_illuminance</td>
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<td>illuminance</td>
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<td>lux</td>
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<td>lux</td>
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<td>lux</td>
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<td>lux</td>
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</tr>
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<tr>
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<td class="first_col">group_interval</td>
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<td>interval</td>
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<td>minute</td>
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<td>minute</td>
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<td>minute</td>
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<td>minute</td>
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</tr>
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<tr>
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<td class="first_col">group_length</td>
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<td></td>
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<td>inch<br/> cm
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</td>
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<td>inch</td>
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<td>cm</td>
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<td>cm</td>
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</tr>
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<tr>
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<td class="first_col">group_moisture</td>
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<td>soilMoist1 <br/> soilMoist2 <br/> soilMoist3 <br/> soilMoist4
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</td>
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<td>centibar</td>
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<td>centibar</td>
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<td>centibar</td>
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<td>centibar</td>
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</tr>
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<tr>
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<td class="first_col">group_percent</td>
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<td>
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cloudcover<br/>extraHumid1 <br/> extraHumid2 <br/> inHumidity <br/> outHumidity <br/>pop<br/>
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rxCheckPercent<br/>snowMoisture
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</td>
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<td>percent</td>
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<td>percent</td>
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<td>percent</td>
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<td>percent</td>
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</tr>
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<tr>
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<td class="first_col">group_power</td>
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<td></td>
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<td>kilowatt<br/>watt</td>
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<td>watt</td>
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<td>watt</td>
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<td>watt</td>
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</tr>
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<tr>
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<td class="first_col">group_pressure</td>
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<td>
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barometer <br/> altimeter <br/> pressure
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</td>
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<td>
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inHg<br/>mbar<br/>hPa<br/>kPa
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</td>
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<td>inHg</td>
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<td>mbar</td>
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<td>mbar</td>
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</tr>
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<tr>
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<td class="first_col">group_pressurerate</td>
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<td>
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barometerRate <br/> altimeterRate <br/> pressureRate
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</td>
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<td>
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inHg_per_hour <br/> mbar_per_hour <br/> hPa_per_hour <br/> kPa_per_hour
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</td>
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<td>inHg_per_hour</td>
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<td>mbar_per_hour</td>
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<td>mbar_per_hour</td>
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</tr>
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<tr>
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<td class="first_col">group_radiation</td>
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<td>maxSolarRad <br/> radiation</td>
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<td>watt_per_meter_squared</td>
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<td>watt_per_meter_squared</td>
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<td>watt_per_meter_squared</td>
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<td>watt_per_meter_squared</td>
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</tr>
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<tr>
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<td class="first_col">group_rain</td>
|
|
<td>rain<br/>ET<br/>hail<br/>snowDepth<br/>snowRate</td>
|
|
<td>inch <br/> cm <br/> mm
|
|
</td>
|
|
<td>inch</td>
|
|
<td>mm</td>
|
|
<td>cm</td>
|
|
</tr>
|
|
<tr>
|
|
<td class="first_col">group_rainrate</td>
|
|
<td>rainRate <br/> hailRate
|
|
</td>
|
|
<td>inch_per_hour <br/> cm_per_hour <br/> mm_per_hour
|
|
</td>
|
|
<td>inch_per_hour</td>
|
|
<td>mm_per_hour</td>
|
|
<td>cm_per_hour</td>
|
|
</tr>
|
|
<tr>
|
|
<td class="first_col">group_speed</td>
|
|
<td>wind <br/> windGust <br/> windSpeed <br/> windgustvec <br/> windvec
|
|
</td>
|
|
<td>mile_per_hour <br/> km_per_hour <br/> knot <br/> meter_per_second <br/> beaufort
|
|
</td>
|
|
<td>mile_per_hour</td>
|
|
<td>meter_per_second</td>
|
|
<td>km_per_hour</td>
|
|
</tr>
|
|
<tr>
|
|
<td class="first_col">group_speed2</td>
|
|
<td>rms <br/> vecavg
|
|
</td>
|
|
<td>mile_per_hour2 <br/> km_per_hour2 <br/> knot2 <br/> meter_per_second2
|
|
</td>
|
|
<td>mile_per_hour2</td>
|
|
<td>meter_per_second2</td>
|
|
<td>km_per_hour2</td>
|
|
</tr>
|
|
<tr>
|
|
<td class="first_col">group_temperature</td>
|
|
<td>appTemp <br/> dewpoint <br/> extraTemp1 <br/> extraTemp2 <br/> extraTemp3 <br/> heatindex <br/>
|
|
heatingTemp <br/> humidex <br/> inTemp <br/> leafTemp1 <br/> leafTemp2 <br/> outTemp <br/> soilTemp1
|
|
<br/> soilTemp2 <br/> soilTemp3 <br/> soilTemp4 <br/> windchill <br/> THSW
|
|
</td>
|
|
<td>degree_C<br/> degree_F <br/> degree_E<br/> degree_K
|
|
</td>
|
|
<td>degree_F</td>
|
|
<td>degree_C</td>
|
|
<td>degree_C</td>
|
|
</tr>
|
|
<tr>
|
|
<td class="first_col">group_time</td>
|
|
<td>dateTime</td>
|
|
<td>unix_epoch <br/> dublin_jd
|
|
</td>
|
|
<td>unix_epoch</td>
|
|
<td>unix_epoch</td>
|
|
<td>unix_epoch</td>
|
|
</tr>
|
|
<tr>
|
|
<td class="first_col">group_uv</td>
|
|
<td>UV</td>
|
|
<td>uv_index</td>
|
|
<td>uv_index</td>
|
|
<td>uv_index</td>
|
|
<td>uv_index</td>
|
|
</tr>
|
|
<tr>
|
|
<td class="first_col">group_volt</td>
|
|
<td>consBatteryVoltage <br/> heatingVoltage <br/> referenceVoltage <br/> supplyVoltage
|
|
</td>
|
|
<td>volt</td>
|
|
<td>volt</td>
|
|
<td>volt</td>
|
|
<td>volt</td>
|
|
</tr>
|
|
<tr>
|
|
<td class="first_col">group_volume</td>
|
|
<td></td>
|
|
<td>cubic_foot<br/> gallon<br/> liter
|
|
</td>
|
|
<td>gallon</td>
|
|
<td>liter</td>
|
|
<td>liter</td>
|
|
</tr>
|
|
<tr>
|
|
<td class="first_col">group_NONE</td>
|
|
<td>NONE</td>
|
|
<td>NONE</td>
|
|
<td>NONE</td>
|
|
<td>NONE</td>
|
|
<td>NONE</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
|
|
## Durations {#Durations}
|
|
|
|
Rather than give a value in seconds, many durations can be expressed using a shorthand notation.
|
|
For example, in a skin configuration file `skin.conf`, a value for `aggregate_interval` can be
|
|
given as either
|
|
|
|
aggregate_interval = 3600
|
|
|
|
or
|
|
|
|
aggregate_interval = 1h
|
|
|
|
The same notation can be used in trends. For example:
|
|
|
|
<p>Barometer trend over the last 2 hours: $trend(time_delta='2h').barometer</p>
|
|
|
|
Here is a summary of the notation:
|
|
|
|
| Example | Meaning |
|
|
|---------|--------------------|
|
|
| `10800` | 3 hours |
|
|
| `3h` | 3 hours |
|
|
| `1d` | 1 day |
|
|
| `2w` | 2 weeks |
|
|
| `1m` | 1 month |
|
|
| `1y` | 1 year |
|
|
| `hour` | Synonym for `1h` |
|
|
| `day` | Synonym for `1d` |
|
|
| `week` | Synonym for `1w` |
|
|
| `month` | Synonym for `1m` |
|
|
| `year` | Synonym for `1y` |
|
|
|
|
|
|
|
|
## Class `ValueTuple` {#ValueTuple}
|
|
|
|
A value, along with the unit it is in, can be represented by a 3-way
|
|
tuple called a "value tuple". They are used throughout WeeWX. All
|
|
WeeWX routines can accept a simple unadorned 3-way tuple as a value
|
|
tuple, but they return the type `ValueTuple`. It is useful
|
|
because its contents can be accessed using named attributes. You can
|
|
think of it as a unit-aware value, useful for converting to and from
|
|
other units.
|
|
|
|
The following attributes, and their index, are present:
|
|
|
|
<table>
|
|
<tr class="first_row">
|
|
<td>Index</td>
|
|
<td>Attribute</td>
|
|
<td>Meaning</td>
|
|
</tr>
|
|
<tr>
|
|
<td>0</td>
|
|
<td class="code">value</td>
|
|
<td>The data value(s). Can be a series (e.g., <span class="code">[20.2, 23.2, ...]</span>) or a scalar
|
|
(e.g., <span class="code">20.2</span>)
|
|
</td>
|
|
</tr>
|
|
<tr>
|
|
<td>1</td>
|
|
<td class="code">unit</td>
|
|
<td>The unit it is in (<span class="code">"degree_C"</span>)</td>
|
|
</tr>
|
|
<tr>
|
|
<td>2</td>
|
|
<td class="code">group</td>
|
|
<td>The unit group (<span class="code">"group_temperature"</span>)</td>
|
|
</tr>
|
|
</table>
|
|
|
|
It is valid to have a datum value of `None`.
|
|
|
|
It is also valid to have a unit type of `None` (meaning there is no
|
|
information about the unit the value is in). In this case, you won't be
|
|
able to convert it to another unit.
|
|
|
|
Here are some examples:
|
|
|
|
``` python
|
|
from weewx.units import ValueTuple
|
|
|
|
freezing_vt = ValueTuple(0.0, "degree_C", "group_temperature")
|
|
body_temperature_vt = ValueTuple(98.6, "degree_F", group_temperature")
|
|
station_altitude_vt = ValueTuple(120.0, "meter", "group_altitude")
|
|
|
|
```
|
|
|
|
## Class `ValueHelper` {#ValueHelper}
|
|
|
|
Class `ValueHelper` contains all the information necessary to do
|
|
the proper formatting of a value, including a unit label.
|
|
|
|
### Instance attribute
|
|
|
|
#### ValueHelper.value_t
|
|
|
|
Returns the `ValueTuple` instance held internally.
|
|
|
|
### Instance methods
|
|
|
|
#### ValueHelper.__str__()
|
|
|
|
Formats the value as a string, including a unit label, and returns it.
|
|
|
|
#### ValueHelper.format(format_string=None, None_string=None, add_label=True, localize=True)
|
|
|
|
Format the value as a string, using various specified options, and
|
|
return it. Unless otherwise specified, a label is included.
|
|
|
|
Its parameters:
|
|
|
|
- `format_string` A string to be used for formatting. It must
|
|
include one, and only one, [format
|
|
specifier](https://docs.python.org/3/library/string.html#formatspec).
|
|
|
|
- `None_string` In the event of a value of Python `None`, this string
|
|
will be substituted. If `None`, then a default string from
|
|
`skin.conf` will be used.
|
|
|
|
- `add_label` If truthy, then an appropriate unit label will be
|
|
attached. Otherwise, no label is attached.
|
|
|
|
- `localize` If truthy, then the results will be localized. For
|
|
example, in some locales, a comma will be used as the decimal specifier.
|