Before we use any constants, let’s make them easy to find.
Sort by symbol
Good for glancing. E.g. scanning for
c is quicker than hunting for ‘Speed of light’.
Sort by title
Good for browsing. E.g. all the electron related constants are grouped together.
Previously, you have to double-click to insert.
Now you can press:
⌘ ↩ (command-return)
If you want to insert the value instead, press:
⌥ ⌘ ↩ (option-command-return)
The History drawer also has 2 different insertions.
Find out what they are. It’s quite handy.
To illustrate, let’s insert the first 3 constants:
Fine structure constant
Magic Number remembers your recently used constants:
The most recent one is at the top of the list.
Let’s clear the display before we go on. With many constants on the display, it can get confusing.
Press ⌃K (control-K) to insert the top (most recent) constant.
Press again for the next one down.
Repeat again to cycle through the list.
By default, Magic Number remembers the 5 most recent constants. You can have more.
With 10 constants to cycle through, there is another handy shortcut for you.
It cycles through the constants in reverse.
One last thing, you can use these shortcuts anytime without opening the drawer.
You can use the memory feature to make constants.
Memories are like variables. You can use letters a, b, k, m, n.
For example, to set m to 42, enter
m = 42
and press return.
Making it better
Sometimes those letters do not suit our needs. We can:
- Give it a meaningful name
Instead of ‘m’ you can have longer name like ‘mass’.
- Create a custom shortcut
Since memories are also available as menu, you can create a custom shortcut. (See the last tip.)
The mass of deuteron is 3.343586e-27 kg.
Let’s save it for the future.
Enter ‘m = 3.343586e-27’ and hit return:
‘m’ is not a memorable name. Let’s rename it to ‘dm’.
Go to menu: Calculation > Memory Options…
You can see the new name is reflected instantly:
At this point, it’s natural to set a custom shortcut,
maybe option-d for deuteron. But let’s wait a minute.
Since custom shortcut ties to the memory name,
make sure you are happy with the name first.
The current name is OK.
But we can do better. Time for the next tip.
Constants such as Planck temperature has a subscript.
We can make subscript with underscore ‘_’.
For our deuteron mass example:
Let’s try something descriptive:
In math, we often have variables like a1 , a2 , a3 … etc.
If your name ends with a number, it will conveniently become a subscript.
No need for ‘_’.
- In practice you probably use ‘m_d’ as the name for deuteron mass so that it is consistent with constants like electron mass.
- If you really want ‘deuteron_mass’ instead of ‘deuteronmass’,
add ‘_’ before the name so that it becomes ‘_deuteron_mass’.
See the hidden value
Sometimes it’s useful to see the value behind a constant.
Maybe for checking or as a confirmation.
Imagine you are not sure what h is.
Press ⌘I to see its value briefly.
This trick also works for memories and tax rates.