set_calibration
Description:
Adjusts the rate and time of this.
A rate of 1/1 is the normal speed of the clock. Values bigger than 1/1 make the clock go faster.
internal and external are calibration parameters that arrange that
get_time should have been external at internal time
internal. This internal time should not be in the future; that is, it should be less than the value of
get_internal_time when this function is called.
Subsequent calls to get_time will return clock times computed as follows:
``` C time = (internal_time - internal) * rate_num / rate_denom + external ```
This formula is implemented in adjust_unlocked. Of course, it tries to do the integer arithmetic as precisely as possible.
Note that get_time always returns increasing values so when you move the clock backwards, get_time will report the previous value until the clock catches up.
Parameters:
| this |
a Clock to calibrate |
| external |
a reference external time |
| rate_num |
the numerator of the rate of the clock relative to its internal time |
| rate_denom |
the denominator of the rate of the clock |
| internal |
a reference internal time |