CLAD Homework 5 Solutions
1. C
Modifying the SubVI to have Error clusters that can be used from the calling
VI will ensure that the SubVI executes when you want it to, when it receives
the required error in input. Utilizing error clusters in subVIs is the best way of
enforcing data flow since it also allows for proper error handling.
2. D
Since automatic error handling is enabled in the main VI, and the error
terminals of the subVI are not wired, LabVIEW automatically handles the error
by displaying a dialog.
3. D
Icons cannot be edited from the functions palette. SubVI icons can be edited
by right-clicking the icon in the upper right of the VI and selecting Edit Icon.
4. A
The documentation window in VI Properties is the only place to edit the
information about the VI that appears in Context Help.
5. D
LabVIEW represents arrays as a list of bytes containing a header and array
data. The header contains a 4-byte integer for each dimension that specifies
the length of that dimension. Following the header is the actual array data. In
the question, the array has two dimensions. There are 4 bytes in the header
for each dimension for a total of 8 bytes in the header. Since the array is
composed of 8-bit, or 1-byte integers, there is a total of 9 bytes of actual array
data. This makes a total of 17 bytes being written to file.
6. C, D
A bold input in the Context Help window indicates a Required input. Because
of the nature of Required inputs, the VI will have a broken run arrow if the
input is unwired.
7. D
Even though automatic error handling is enabled, all of the functions have
error clusters wired to their outputs. This prevents LabVIEW from interrupting
execution and displaying a dialog to the user even though an error has
occurred. If any of the functions had no error cluster wired to their outputs,
then LabVIEW would display a dialog and suspend execution.
8. A
A single Boolean value uses one byte of memory in LabVIEW. Answer A is
the correct answer because the Boolean Array to Number converts 8 Boolean
values, or 8 bytes, into a single 8-bit integer value, or 1 Byte. Thus the total
amount of data written is 1 byte. Answer B writes 1 byte for each Boolean
value, and answers C and D write strings. Each character in a string uses 1
byte, so answers C and D each write multiple bytes of data to the file.
9. A
Tab-delimited ASCII are text files that can be read in Excel. Since most
people are very familiar with Excel, it is a great way to share information.
10. B
Polymorphic VIs adapt to different data types. A polymorphic VI is a collection
of VIs with the same connector pane patterns. Each VI in the collection is an
instance of the polymorphic VI, and each instance has at least one input or
output terminal that accepts a different data type than in the other instances.
To create a Polymorphic VI, you must select File >> New… >> Polymorphic
VI and then configure it to use the VIs that you want.