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| Code Block | ||
|---|---|---|
| ||
precip = read("precip.grib")
n = count(precip) # the number of fields in the fieldset
precip_3h = precip[2, n] - precip[1, n-1]
return precip_3h |
Visualise the macro.
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If you drop the precip_shade visdef icon into the plot, it may become blank! There is one more trick: we have created a derived field, and this changes the automatic scaling algorithm used when plotting. Precipitation is stored in metres, but we want to display it in mm. Modify the precip_shade icon and set:
| Grib Scaling of Derived Fields | On |
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