Correctly handle GINI negative calibration values #488
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GINI calibration values can be negative (for the data value range), and GEMPAK uses the left most bit of the stored integer to designate the signedness. Fixes Unidata#480 Minor addition - since the long_name attribute was there and so close, go ahead an add the standard_name attribute to the x and y coordinate variables.
| // 0x7FFFFFFF -> left-most bit is zero, all the rest are 1's. | ||
| // The bit-wise & results in flipping the first bit of "mind" (because we know it is 1 at this point, and | ||
| // 1 & 0 -> 0) while retaining the rest of the pattern of mind (because 0 & 1 -> 0, 1 & 1 -> 1). | ||
| // To negate, just use the negative sign...we could do (mind & 0x7FFFFFFF) + 1, but let's not hang out |
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I don't understand the "+1" bit here
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Missed the tilde...should be ~(mind & 0x7FFFFFFF) + 1 Update incoming
dopplershift
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Sep 22, 2020
lesserwhirls
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Oct 8, 2020
Backport of Unidata/netcdf-java#488 GINI calibration values can be negative (for the data value range), and GEMPAK uses the left most bit of the stored integer to designate the signedness. Fixes Unidata/netcdf-java#480. Minor addition - since the `long_name` attribute was there and so close, go ahead an add the `standard_name` attribute to the `x` and `y` coordinate variables.
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GINI calibration values can be negative (for the data value range), and GEMPAK uses the left most bit of the stored integer to designate the signedness. Fixes #480
Minor addition - since the
long_nameattribute was there and so close, go ahead an add thestandard_nameattribute to thexandycoordinate variables.This change is