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Fix off-by-one calculation of number of points - #42
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When changing a linear scan positioner step size (PnSI), the number of points (NPTS) is sometimes incorrectly calculated as one less than it should be. For example, with positioner 1 configured as SCAN MODE: LINEAR START: 0.0 CENTER: -0.7 END: -1.4 STEP: -0.05 WIDTH: -1.4 ABS/REL: RELATIVE , NPTS is calculated as 28, but that's wrong; it should be 29. This miscalculation occurs when assigning the result of the calculated NPTS double expression to the NPTS variable of type epicsInt32. In the above example, the calculated NPTS double expression evaluates to 28.9999999999999964 , but when assigned to the NPTS variable of type epicsInt32, the value becomes 28 which is of course wrong. Fix this and similar NPTS variable assignments by rounding the result of the double expression before assigning to the NPTS variable of type epicsInt32.
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When changing a linear scan positioner step size (PnSI), the number of points (NPTS) is sometimes incorrectly calculated as one less than it should be. Fix this and similar NPTS variable assignments by rounding the result of the
doubleexpression before assigning to the NPTS variable of typeepicsInt32. See also the Same sscan record step size for all positioners not possible? EPICS Tech-Talk mailing list thread.