Include the constant "Tau", the circle constant

[jdunham]

Please add the circle constant tau, to the Math & Scientific Constants palette.  Happy Tau day!  (see more at http://tauday.com/)

[X.]

[RavensFan]

Yes.  Let's clutter up the palette with a constant that nobody has ever heard of before.  Or ever actually used.  I guess if it wasn't June 28, I would have never heard of it either.

[labview4steve]

Tau is a useful number!
I like the idea of adding LOTS more constants to thisTab... Almost everyday I used various engineering or scientific Constants.... We could have an entire Tab devoted to the different Pi ratios anyone wanted, or electrical constants , or physical or engineering constants...

Also, how is this tab already cluttered?
There are only 5 Pi ratios, 5 Logarithim, 4 physical, and 3 chemical constants.
There are hardly ANY that people use...
We could have an astronomical Tab (ie planet mass, orbital time, etc),
More Physical (ie electron mass, neutron mass etc),
Engineering tabs.<<< This one ESPECIALLY - its used in engineering mostly isn't it?

As far a no one hearing of it or ever using it, thats like saying who's ever heard of or used planks constant, or fourier or linear programming, or any of the other functions in labview that YOU have never used.
That's pretty silly!
Getting that out of the way, X-) has already pointed out that it exists already under a different name. ie (2 times Pi) = t (tau)  ... So I think what jdunham may have been suggesting was to RE-LABEL the icon to the  - but like Ravens Fan he may have not properly looked at the Tab and seen that its already there just disguised!

[jdunham]

Oh, I know it's there, it just has the wrong graphic.  I was going to also suggest adding  (tau/2) as well, but I thought no one would take it seriously 

It seems like if NI can make an alternate graphic for feedback nodes (the "Z-1" appearance), they could do the right thing by Tau as well.

[labview4steve]

Update:

One of the most common constants used (unless you design space probes) would be:

Acceleration due to gravity g = 9.80665 m/s²

But, instead we have:
the UNIVERSAL Gravitational constant G = 6.67384(80)×10−11
 m³·kg⁻¹·s⁻²

Why? Did Nasa want this instead?
Surely the most common ones would be there first.

I checked a site that has a list of many fundamental constants:
http://physics.nist.gov/cgi-bin/cuu/Category?view=html&All+values.x=67&All+values.y=12
whichs lists over a hundred by the looks of it.

But also has a list of the most common fundamental constants used in science.

There are 15 listed that don't appear in the labview Constants Tab and many are more common than the ones we have.. ie:

atomic mass constant
Boltzmann constant
conductance quantum
electric constant
electron mass
electron volt
Faraday constant
fine-structure constant
inverse fine-structure constant
magnetic constant
magnetic flux quantum
Planck constant over 2 pi
proton mass
proton-electron mass ratio
Stefan-Boltzmann constant

yet we only have these 7 (out of hundreds?):

Planck constant
elementary charge
speed of light in vacuum
Newtonian constant of gravitation
Avogadro constant
Rydberg constant
molar gas constant.

Wikipedia has a list of many constants...
http://en.wikipedia.org/wiki/Physical_constant
And some additional on this page... (some are duplicated)
http://www.chemie.fu-berlin.de/chemistry/general/constants_en.html

Why do we have the constants we have and not others? It seems rather arbitrary, except Pi and e of course!... But we could have many many more.

[labview4steve]

Ok, jdunham, you would probably be right...no one would take it seriously....
I agree with you though about it in general.
What about lots of constants in general like I suggested?

[Brian_Powell]

By the way, in June 2011, CODATA released updated values for the physical "constants".  As we've done in the past, we will update the constants in LabVIEW as needed to reflect the world's latest estimates of these values.  I haven't checked to see which ones might affect LabVIEW.

In what way do you think we should handle compatibility?  Do you still want to be able to use the 2006 values?  2002 values?  If you come up with a good suggestion, I'd post it as a new idea.  I suspect this "tau" discussion is going to be declined before long. 🙂

[Darin.K]

If you are looking for constants to update, how about looking at tau (2 pi), tau/2 (pi) and tau/4 (pi/2).  I would expect these values to be as close as possible to the very-well-known values (do not need CODATA) for all representations.  If you examine the EXT values of these constants, they are off by ~75 epsilon (pi), ~150 epsilon (2 pi) or ~300 epsilon (pi/2).  You only get 0-2 more digits by going to EXT.

Of course it is tricky to examine the actual values because any attempt to display an EXT number by creating an indicator or constant seems to lop off the precision to match DBL precision. 

Not only could tau be the more natural choice for the circle constant, it could also have a more accurate value than the current 2 pi approximation.

[X.]

R U sure?

pi_tagoras    = 3.14159 26535 89793 23846...

pi_LabVIEW = 3.14159 26535 89793 11000 (20 decimal places DBL)

epsilon         = 0.00000 00000 00000 22204

So the "error" seems within epsilon to me.

This is what I used (LV 2010 SP1):

[Darin.K]

Did you try EXT?