DECEMBER 2019 MACWORLD 35that’s not
recommended for
political decision
making, it can be
useful when you’re
tweaking sizes for a
wall hanging or how
many miles a day to
drive for a trip.
New in version 3
are two features that
require adhering more
closely to syntax than
most of others in the
app. A “rule of three”
feature in which
Soulver can fill in the blank. This is great
for proportions. You state one of these in
the form “number is to number as number
is to what,” as in 9 is to 16 as 27 is
to what (answer: 48).
With dates, you can’t enter arbitrary
calculations, as Soulver relies on an Apple
math library for dates. But you can find a
lot of results that would otherwise involve
manually counting off days or weeks on a
calculator. June 1, 2019 - 6 weeks, for
instances, gives you April 20.
A common issue for those of us who
transfer large files over networks and the
internet is getting a decent estimate of the
span of time that copying those items will
take or what the capacity of my throughput
is. I turn to Soulver regularly for this, as it
accepts calculations like:
> (120 Mb/second) × 100 hours
in TB (5.4TB)
> 1 TB / (120 Mb/second) in
hours (18.5 hours)
Capitalization remains important in
units here as in others: a megabyte (a
million bytes) is capital M and B (MB), while
megabit (a million bits) is capital M and
lowercase b (Mb). While this long-running
similarity can be a problem in other realms,
it’s easy to be off by a factor of eight here.
Soulver shows a lot of numbers after
the decimal point for results that don’t
divide or multiply neatly, which is called
precision. The default is 10 digits, which is
useful for certain kinds of mathematical
results and scientific calculation, but far tooDate and time calculations have some limits, but beat looking at a
calendar and counting on one’s fingers.