Missing coercion dot?

[Götz Becker]

Hi again,

I recently found another data conversion I don´t understand. Why isn´t there a coercion dot at the second join numbers?

LV 8.5.1

I know that this isn´t a good style for lowlevel data manipulation, but a hint from LV about the implicit byte that is added would be nice.

[crelf]

On closer inspection, I think you're right - there should be a coercion dot there...

[Aristos Queue]

Reported to LV R&D as CAR #116157.

[Götz Becker]

Thank you for reporting.

After playing a little with join numbers I came to another behavior I wouldn´t have (naively) expected:

(both results are the same)

The implicit type cast of the signed inputs made total sense to me after a second thought and reminded me to always think (at least) twice about the bits and bytes underneath when using the data manipulation primitives.

[silmaril]

QUOTE (Götz Becker @ Jun 17 2008, 12:28 AM)

The implicit type cast of the signed inputs made total sense to me after a second thought and reminded me to always think (at least) twice about the bits and bytes underneath when using the data manipulation primitives.

Yes I agree that this type cast makes sense. Still, it wouldn't hurt to have coercion dots at those inputs, too.

To split some hairs:

In this example, the I16 values are not really coerced, they are typecasted, which should make a difference for negative numbers.

But that seems to be LabVIEW's normal coercion dot behaviour for converting I16 to U16. If you wire a value of -1 to an U16 input you will get 0xFFFF (which is correct, but I would call this a type cast; a coercion should give the result 0 here as I understand this term).

[Ton Plomp]

QUOTE (Götz Becker @ Jun 16 2008, 03:53 PM)

http://lavag.org/old_files/monthly_06_2008/post-1037-1213624138.png' target="_blank">

One question is the U8 converted or typecasted? With a typecast the U8 is placed in the upper byte of the U16.

Ton

[Aristos Queue]

QUOTE (tcplomp @ Jun 17 2008, 05:13 AM)

One question is the U8 converted or typecasted? With a typecast the U8 is placed in the upper byte of the U16.

You're right that conversion and typecast are behaving differently, but that would change on a machine with different endian-ness.