LabVIEW
part of a bigger code
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Message Edited by krispiekream on 06-09-2008 06:13 PM
krispiekream wrote:
i am trying to learn how to use less sequence structures, and dont try to use local variables.
i have a part of a code i want to simplify. can someone give me pointers on doing so. thanks in advance
- Well, your error out should be an indicator instead of a control. Now simply hook it up to the error out of your subVI.
- That entire case structure handling the error makes no sense. Simply hook up the error terminal and delete the case structure, unbundle, and related code.
- Follow established coding guidelines and use an error-in and error-out.
- It makes little sense to accumulate your pressure array inside a local variable. Use a chart instead of a graph and none of this is needed. If you show the digital display of the chart, you can even eliminate the numeric pressure indicator.
- Keep the representation of you diagram constants consistent. Don't randomly mix blue and yellow. (While LabVIEW will coerce it for you, ignoring representations is a sign of shoddy coding and raises doubt on the competence of the programmer).
- Same for the wire going to the case structure. Use a "not equal zero" and true/false cases for example.
- Can you include the subVI?
- I don't understand your locking gymnastics. It does not seem safe. What else is writing to these globals? (for example there is no obvious guarantee that the lock state is not modified from elsewhere in the time between it is checked outside the case and set inside the case. You could use an action engine instead, that can check AND set (if unset) in one operation or return a set failure (if set).
- How is this VI being called or run? Are you using the "contunous run" button perhaps?
krispiekream wrote:
this is needed because i want to keep all the pressure on a graph and let it run for days. therefore days later i can see how it changed.
What is the data rate? It can be very expensive to accumulate an infinite, and ever growing amount of data in a local variable. If you want to keep a record of the data, you should stream it to disk and still only use a chart.
If you keep the data history only in memory (chart, local variabel, shift register), you will loose it all if the computer crashes e.g. on the third day. Not a good idea!
That's the function of the digital display of a chart, you still don't need a seperate indicator. Always keep the code simple!
krispiekream wrote:
i need the numeric pressure indicator to know what is the current pressure reading. ?
