Darren's Weekly Nugget 05/11/2009

[Darren]

There was a lot of buzz over on LAVA last week regarding some neat LabVIEW behavior that I assumed everybody already knew.  So here's a nugget to make it official.

When you drop a Numeric Constant on the block diagram (my Quick Drop shortcut for numeric constant is 'nc'), its data type is I32.  If you want to change the data type to DBL, you don't have to go through the Right-click > Representation menu.  Instead, simply type a value in the constant that has a decimal point in it.  Even if you don't want to specify a fractional value, but you still want to change the data type, just end your number with a decimal point.  For example, if you drop the constant, and you want it to have a DBL value of "1", then just type "1." into the constant, and there you go...blue to orange in the blink of an eye!  

[PaulG.]

Very sweet.

[Harold_Timmis]

lol that one of the first things i learned with labview 🙂

[RavensFan]

---

Harold Timmis wrote:

lol that one of the first things i learned with labview 🙂

---

That's funny.  That is the most recent thing I've learned with LabVIEW.

I hadn't heard about this one before and is so simple, but good to know.

[altenbach]

---

Darren wrote:

Even if you don't want to specify a fractional value, but you still want to change the data type, just end your number with a decimal point.

---

Yes, use it all the time. Has been around forever. (Just tried in LabVIEW 4.0.1 and it works) 😄

Here's a wish for improvent: Once I do this, I would prefer if "adapt to datatype" would become disabled. Right now, everything can be nicely wired up in all orange, but if I then change the constant to e.g. 2, it turns blue and forces coercion dot. I need to remember to enter the decimal point every time I edit the constant.

LabVIEW should be smart enought to not automatically change the datatype if a coercion would result. 🙂

[Harold_Timmis]

yeah my manager taught me it.

[Spectre_Dave]

I have used this for years - Very handy

[Thoric]

Yup, been using this one since as far back as I can remember

Any way to easily change the representation from I32 to, say, U16 ?

[Darren]

---

Thoric wrote:

Any way to easily change the representation from I32 to, say, U16 ?

---

Other than using the right-click Representation menu, not really.  I would look for another U16 data type (wire, terminal, constant,etc.) and right-click > Create Constant I guess.

-D

[smercurio_fc]

I've also known about that for a while, but can't remember how and when I learned about it. The trick also works for making a complex constant by typing "0+0i" when you drop the numeric constant. The datatype will automatically be changed to CDB. Not sure if this was introduced at the same time, though, so I don't know how far back this goes.