You should just test both approaches and find out if the performance difference is acceptable. In a recent thread on this group, there was an example of creating many pynodes vs using cmds. At lower numbers you may not perceive a difference. At higher numbers it could be seconds vs subseconds
On Thu, 12 Mar 2015 4:08 PM Panupat Chongstitwattana <panup...@gmail.com> wrote: > Thank you every one. > > The current script I trying this is about retrieving hundreds or even > thousands of names from Json/SQL and adjust maybe 1 or 2 attributes of > each. Looping through strings creating PyNode over and over only to perform > 1 operation... would this bother you or do you think it shouldn't matter? I > get a feeling PyMel maybe more suitable for scripts that manipulate fewer > number of objects where you're adjusting many attributes. > > > > On Thursday, March 12, 2015 at 12:44:54 AM UTC+7, Geordie Martinez wrote: > >> If you'd like to learn more about pymel this is a great book. >> check out Practical Maya Programming with Python: >> http://www.amazon.com/Practical-Programming-Python-Robert-Galanakis/dp/ >> 1849694729/ref=sr_1_1?ie=UTF8&qid=1426095687&sr=8-1& >> keywords=practical+maya+programming+with+python >> >> and I hear these videos are okay ;) (shameless plug) >> http://www.cgcircuit.com/course/intro-to-pymel-part-1 >> >> >> >> >> >> On Wed, Mar 11, 2015 at 6:21 AM, Paul Molodowitch <elro...@gmail.com> >> wrote: >> > From a functional standpoint, there isn't a difference. There may be a >>> performance difference, but unless you're making thousands, I wouldn't >>> worry about it. >>> >>> Generally speaking, if I usually expect it to exist, and want to use it >>> as a PyNode if it does, I'll do the try/except thing. One note though - >>> you should probably do: >>> >>> try: >>> pmc.PyNode(string) >>> except pmc.MayaNodeError: >>> print "something" >>> >>> It's bad practice to have blanket except statements** - particularly if >>> you're "expecting" a certain type of error. Get in the habit of having >>> targeted try excepts, and you'll save yourself from headaches down the road. >>> >>> - Paul >>> >>> **There are always exceptions, of course - for instance, if you're >>> running an app and don't want an unknown error to bring everything to a >>> halt, it can make sense to have some generic high-level try/except >>> statements. And in those cases, you'll probably want to at least print >>> some sort of warning or traceback, or maybe log it to an error log, or >>> email a bug report, etc. Also, even then, it's better to do "except >>> Exception as e:" or "except Exception:" instead of "except:", because the >>> latter will catch strange things you almost certainly don't want to - ie, >>> if the user presses ctrl-c, or even if you've explicitly tried to call >>> sys.exit! >>> >>> >>> On Wed, Mar 11, 2015 at 12:32 AM, Panupat Chongstitwattana < >>> panu...@gmail.com> wrote: >>> >>>> Ah thank you. Such a silly mistake :( >>>> >>>> Is there any draw back if I don't check objExists but instead go for >>>> this? >>>> >>>> try: >>>> PyNode(string) >>>> except: >>>> print "something" >>>> >>>> >>>> >>>> On Wednesday, March 11, 2015 at 2:02:06 PM UTC+7, Justin Israel wrote: >>>>> >>>>> You have a typo between the two ways you format the string : >>>>> >>>>> tmpname = "%smaster_crtl" % sel.namespace() >>>>> tmp = "%smaster_ctrl" % selects[0].namespace() >>>>> >>>>> crtl vs ctrl >>>>> >>>>> On Wed, 11 Mar 2015 7:02 PM Panupat Chongstitwattana < >>>>> panu...@gmail.com> wrote: >>>>> >>>>>> Hi. >>>>>> >>>>>> I ran into another problem. objExists is returning different result >>>>>> when I put it in a for loop. >>>>>> >>>>>> selects = pmc.selected() >>>>>> >>>>>> for sel in selects: >>>>>> tmpname = "%smaster_crtl" % sel.namespace() >>>>>> print tmpname >>>>>> print pmc.objExists(tmpname) >>>>>> # SC05A_0110_ECh_LoopAnim_v002:SC05A_0020_Extra_Cheer_LoopAnim >>>>>> _v001:exMaleHair001:master_ctrl >>>>>> # False >>>>>> >>>>>> tmp = "%smaster_ctrl" % selects[0].namespace() >>>>>> print tmp >>>>>> print pmc.objExists(tmp) >>>>>> # SC05A_0110_ECh_LoopAnim_v002:SC05A_0020_Extra_Cheer_LoopAnim >>>>>> _v001:exMaleHair001:master_ctrl >>>>>> # True >>>>>> >>>>>> What could be the cause of this? >>>>>> >>>>>> >>>>>> -- >>>> >>> -- > You received this message because you are subscribed to the Google Groups > "Python Programming for Autodesk Maya" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to python_inside_maya+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/python_inside_maya/1e01a0a8-fdb0-4af8-92c9-c8580c9ff862%40googlegroups.com > <https://groups.google.com/d/msgid/python_inside_maya/1e01a0a8-fdb0-4af8-92c9-c8580c9ff862%40googlegroups.com?utm_medium=email&utm_source=footer> > . > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Python Programming for Autodesk Maya" group. 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