User:Orso.b.schmid: Difference between revisions
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<div class="rightmenu"> | |||
__TOC__ | |||
</div> | |||
Ciao, | Ciao, | ||
I am Orso, an Italian Vectorscripter since many years. I feel very comfortable with Vectorscript | I am Orso, an Italian Vectorscripter since many years. Some of you might know me from Vectorlab or the comments on the present Developer wiki. I feel very comfortable with Vectorscript but will now switch over to Python for even more power. I will try to share here comments, problems -and solutions- from the point of view of a non-programmer. --[[User:Orso.b.schmid|Orso.b.schmid]] ([[User talk:Orso.b.schmid|talk]]) 08:13, 17 May 2015 (EDT) | ||
I will try to share here comments, problems -and solutions- from the point of view of a non-programmer. --[[User:Orso.b.schmid|Orso.b.schmid]] ([[User talk:Orso.b.schmid|talk]]) 08:13, 17 May 2015 (EDT) | |||
If you add comments, please use the full wiki formatting, easily available clicking on ''Advanced'' while on edit mode and don't forget to sign up your comment using <nowiki>--~~~~</nowiki>! | |||
== Vectorlab Archives == | |||
Here is the List Browsers article from the now dead Vectorlab site: | |||
* List Browsers ([[:Media:Vectorlab_ListBrowsers_WebArchives.zip| Vectorlab ListBrowsers Web Archives.zip]]) | |||
I stored some of the Vectorlab sites: | |||
== VS - Py Rosetta Stone == | |||
{| class="wikitable" | |||
! style="width:20%"| Description | |||
! style="width:40%"| Vectorscript | |||
! style="width:40%"| Python | |||
|- style="vertical-align: top;" | |||
| '''Statement ending:''' | |||
| '''Semicolon always needed''' | |||
* <code>AlrtDialog('test 1') </br> AlrtDialog('test 2') { error }</code> | |||
* <code>AlrtDialog('test 1'); AlrtDialog('test 2'); { OK }</code> | |||
* <code>AlrtDialog('test 1') AlrtDialog('test 2') { error }</code> | |||
| '''Semicolon needed only for multiple statements on one line:''' | |||
* <code>vs.AlrtDialog('test 1') </br>vs.AlrtDialog('test 2') # OK</code> | |||
* <code>vs.AlrtDialog('test 1'); vs.AlrtDialog('test 2') # OK</code> | |||
* <code>vs.AlrtDialog('test 1') vs.AlrtDialog('test 2') # error</code> | |||
Error Message: SyntaxError: invalid syntax | |||
|- style="vertical-align: top;" | |||
| '''Case sensitivity''' | |||
| '''Not case sensitive:''' | |||
* <code>AlrtDialog('test'); { OK }</code> | |||
* <code>alrtDialog('test'); { OK }</code> | |||
* <code>alrtdialog('test'); { OK }</code> | |||
* <code>ALRTDIALOG('test'); { OK }</code> | |||
| '''Case sensitive:''' | |||
* <code>vs.AlrtDialog('test') # OK </code> | |||
* <code>vs.alrtDialog('test') # error</code> | |||
* <code>vs.alrtdialog('test') # error</code> | |||
* <code>vs.ALRTDIALOG('test') # error</code> | |||
Error Message: AttributeError: 'module' object has no attribute 'vs.ALRTDIALOG' | |||
|- style="vertical-align: top;" | |||
| '''Empty brakes for functions''' | |||
: don't forget in python the empty brakets for routines without parameters, this rises errors that are so tricky to find. | |||
| '''Can be without brakets''' | |||
* <code>FSActLayer; { no paramters: brakets not needed }</code> | |||
* <code>MySubroutine;</code> | |||
| '''Can't be without brakets''' | |||
* <code>vs.FSActLayer()</code> | |||
* <code>MySubroutine()</code> | |||
Error Message: - none! be careful! - | |||
|- style="vertical-align: top;" | |||
| '''Empty handles''' | |||
: do pay attention also to the variable scope (see below). | |||
| | |||
* <code>h <> NIL</code> | |||
| | |||
* <code>h != None</code> | |||
* <code>h != vs.Handle() # not inited instance of a handle, how cryptic</code> | |||
|- style="vertical-align: top;" | |||
| '''Variable scope''' | |||
: perhaps the largest source of error for the vectorscripter transitioning to python | |||
| | |||
'''Global wins over local:''' | |||
* Variables must be declared | |||
* Subroutines "see" their own variables and those of any parent function/procedure where they are contained. | |||
<code lang="pas"> | |||
{ GLOBAL ACCESS } | |||
{ parent of subroutine "Increment" } | |||
PROCEDURE Main; | |||
VAR | |||
{ good praxis: label globals with "g" } | |||
gIndex, gNum : INTEGER; | |||
{ subroutine } | |||
PROCEDURE Increment; | |||
BEGIN | |||
{ gNum is not defined in this subroutine | |||
the parser climbs up parent containers | |||
until it finds a declaration for the var gNum. | |||
In this case it can be found in Main } | |||
gNum := gNum +1; | |||
SysBeep; | |||
END; | |||
BEGIN | |||
gNum := 10; { init } | |||
FOR gIndex := 1 TO 10 DO | |||
Increment; { increments the variable gNum } | |||
AlrtDialog(Concat(gNum)); | |||
{ returns 20 } | |||
END; | |||
Run(Main); | |||
</code> | |||
| | |||
'''Local wins over global:''' | |||
* Variables must NOT be declared | |||
* Subroutines create automatically a local instance of any used variable. | |||
<code lang="py"> | |||
# LOCAL ACCESS | |||
# subroutine | |||
def Increment(): | |||
# gNum is not defined in this subroutine | |||
# the parser creates a local instance of the var gNum! | |||
gNum +=1 | |||
vs.SysBeep | |||
gNum = 10 # init | |||
for gIndex in range(1, 10): | |||
Increment | |||
# increments the variable gNum | |||
# but only inside Increment! | |||
vs.AlrtDialog(str(gNum)) | |||
# returns 10! The global var didn't set | |||
</code> | |||
<code lang="py"> | |||
# GLOBAL ACCESS: CORRECT | |||
# subroutine | |||
def Increment(): | |||
# gNum is not defined in this subroutine | |||
# tell the parser that you want to edit gNum global! | |||
global gNum | |||
gNum +=1 | |||
vs.SysBeep() | |||
gNum = 10 # init | |||
# please observe that the range is NOT 1, 10! | |||
for gIndex in range(0, 10): | |||
Increment() | |||
# increments the variable gNum | |||
# but only inside Increment! | |||
vs.AlrtDialog(str(gNum)) | |||
# returns 20 | |||
</code> | |||
<code lang="py"> | |||
# GLOBAL ACCESS: WRONG | |||
# subroutine | |||
def Increment(): | |||
# gNum is not defined in this subroutine | |||
# tell the parser that you want to edit gNum global! | |||
global gNum | |||
gNum +=1 | |||
vs.SysBeep() | |||
# no init! | |||
for gIndex in range(0, 10): | |||
Increment() | |||
# increments the variable gNum | |||
# but only inside Increment! | |||
vs.AlrtDialog(str(gNum)) | |||
# rises error | |||
</code> | |||
Error Message: NameError: global name 'gNum' is not defined | |||
|- style="vertical-align: top;" | |||
| '''FOR statements''' | |||
| '''Runs including last value:''' | |||
<code lang="pas"> | |||
{ runs 3 times! 1, 2 and 3 } | |||
FOR i := 1 TO 3 DO | |||
AlrtDialog(Concat(i)); | |||
</code> | |||
| '''Runs excluding last value:''' | |||
<code lang="py"> | |||
# runs 2 times! 1 and 2 | |||
for i in range(1, 3): | |||
vs.AlrtDialog(str(i)) | |||
</code> | |||
|- style="vertical-align: top;" | |||
| '''Colors''' | |||
| | |||
* Color Index: | |||
*: <code>SetPenFore(h, RGBToColorIndex(65535, 0, 0));</code> | |||
*: <code>PenFore(RGBToColorIndex(65535, 0, 0));</code> | |||
* RGB: | |||
*: <code>SetPenFore(h, 65535, 0, 0);</code> | |||
| | |||
* Color Index: | |||
*: <code>vs.SetPenFore(h, vs.RGBToColorIndex(65535, 0, 0)) </code> | |||
* RGB in Tuple: | |||
*: <code>vs.SetPenFore(h, (65535, 0, 0)) </code> | |||
* Hex in Tuple: | |||
*: <code>vs.SetPenFore(h, (0xFFFF, 0, 0))</code> | |||
Warning: don't forget the brakets: | |||
* <code>vs.PenFore((65535, 0, 0)) </code> correct | |||
* <code>vs.PenFore(65535, 0, 0) </code> fails | |||
Error Message: - none! be careful! - | |||
|- style="vertical-align: top;" | |||
| '''Concatenate text''' | |||
| '''Supports implicit conversion:''' | |||
: Both [[VS:Concat| Concat]] and [[VS:Message| Message]] support multiple variable types and convert them into string. | |||
* <code>t := Concat(10, ' fingers'); { OK }</code> | |||
* <code>Message(10, ' fingers'); { OK }</code> | |||
* <code>AlrtDialog(Concat(10, ' fingers')); { OK }</code> | |||
| '''Doesn't support implicit conversion:''' | |||
: For example an integer won't automatically be converted into string. Wrap it in [[VS:Concat| vs.Concat]] or [[VS:Message| vs.Message]], alternatively perform the needed conversion. | |||
* <code>t = 10 + ' fingers' # error</code> | |||
* <code>t = vs.Concat(10, ' fingers') # OK</code> | |||
* <code>vs.Message(10, ' fingers') # OK</code> | |||
* <code>vs.AlrtDialog(str(10) + ' fingers') # OK</code> | |||
* <code>vs.AlrtDialog(10 + ' fingers') # error </code> | |||
Error Message: TypeError: unsupported operand type(s) for +: 'int' and 'str' | |||
|- style="vertical-align: top;" | |||
| '''Encryption''' | |||
| Whatever .vs or .px file is linked through your includes, will be encrypted upon running the encrypt command. More infos [[VS:Include_Files_and_Encryption| here]]. | |||
| Create list of your included files in an xml file. Please read [https://techboard.vectorworks.net/ubbthreads.php?ubb=showflat&Number=197639&Searchpage=1&Main=39809&Words=python&Search=true#Post197639 Vlado on Techboard] | |||
|- style="vertical-align: top;" | |||
| '''Python version''' | |||
| | |||
| <code>import sys | |||
ver = sys.version_info</br> | |||
vs.Message(repr(ver))</br> | |||
</code> | |||
|- style="vertical-align: top;" | |||
| '''"import vs"''' | |||
| | |||
| <code>import vs</code> # do I need this? | |||
|- style="vertical-align: top;" | |||
| '''Caching''' | |||
: some caching prevents your script to reflect changes: | |||
| | |||
| varPersistentPythonEngine = 412 { Boolean } | |||
In the SDK starting from VW 2014 we can read: | |||
''When True the Python engine is the same for the execution of all scripts, this solves some issues with Py_Initialize and Py_Finalize. For example, when debugging externally python leaves threas that cause crash if Py_Initialize and Py_Finalize is used for each script call. So, this allows the engine to be preserved between calls, however Vectorworks will delete all custom modules and objects defined in the engine prior each execution.'' | |||
|} | |||
== Lists == | == Lists == | ||
Line 14: | Line 260: | ||
months = "Jan Feb Mar Apr May Jun Jul" | months = "Jan Feb Mar Apr May Jun Jul" | ||
months = months.split() # no splitter defined and it will use the empty space --> ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul'] | months = months.split() # no splitter defined and it will use the empty space --> ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul'] | ||
months[2] # note that the index is 0-based | months[2] # --> 'Mar' note that the index is 0-based | ||
months2 = "Jan, Feb, Mar, Apr, May, Jun, Jul" | months2 = "Jan, Feb, Mar, Apr, May, Jun, Jul" | ||
months2.split(', ') # | months2.split(', ') # --> ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul'] use comma and empty space as splitter | ||
months.append('Jul') # | months.append('Jul') # --> ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul'] append adds an item to a list | ||
months.pop() # pop fetches the last item of a list | months.pop() #- -> 'Jul' pop fetches the last item of a list | ||
', | ', sunny '.join(months) # --> ', sunny Jan, sunny Feb, sunny Mar, sunny Apr, sunny May, sunny Jun, sunny Sep' | ||
'-'.join(months[1:3]) # --> 'Feb-Mar' | '-'.join(months[1:3]) # --> 'Feb-Mar' | ||
del months[2] # --> ['Jan', 'Feb', 'Apr', 'May', 'Jun', 'Jul'] | del months[2] # --> ['Jan', 'Feb', 'Apr', 'May', 'Jun', 'Jul'] | ||
Line 25: | Line 271: | ||
</code> | </code> | ||
== | == Errors == | ||
Python Error Messages: https://docs.python.org/3/library/exceptions.html | |||
BaseExceptions: | |||
+-- SystemExit | |||
+-- KeyboardInterrupt | |||
+-- GeneratorExit | |||
+-- Exception | |||
+-- StopIteration | |||
+-- ArithmeticError | |||
| +-- FloatingPointError | |||
| +-- OverflowError | |||
| +-- ZeroDivisionError | |||
+-- AssertionError | |||
+-- AttributeError | |||
+-- BufferError | |||
+-- EOFError | |||
+-- ImportError | |||
+-- LookupError | |||
| +-- IndexError | |||
| +-- KeyError | |||
+-- MemoryError | |||
+-- NameError | |||
| +-- UnboundLocalError | |||
+-- OSError | |||
| +-- BlockingIOError | |||
| +-- ChildProcessError | |||
| +-- ConnectionError | |||
| | +-- BrokenPipeError | |||
| | +-- ConnectionAbortedError | |||
| | +-- ConnectionRefusedError | |||
| | +-- ConnectionResetError | |||
| +-- FileExistsError | |||
| +-- FileNotFoundError | |||
| +-- InterruptedError | |||
| +-- IsADirectoryError | |||
| +-- NotADirectoryError | |||
| +-- PermissionError | |||
| +-- ProcessLookupError | |||
| +-- TimeoutError | |||
+-- ReferenceError | |||
+-- RuntimeError | |||
| +-- NotImplementedError | |||
+-- SyntaxError | |||
| +-- IndentationError | |||
| +-- TabError | |||
+-- SystemError | |||
+-- TypeError | |||
+-- ValueError | |||
| +-- UnicodeError | |||
| +-- UnicodeDecodeError | |||
| +-- UnicodeEncodeError | |||
| +-- UnicodeTranslateError | |||
+-- Warning | |||
+-- DeprecationWarning | |||
+-- PendingDeprecationWarning | |||
+-- RuntimeWarning | |||
+-- SyntaxWarning | |||
+-- UserWarning | |||
+-- FutureWarning | |||
+-- ImportWarning | |||
+-- UnicodeWarning | |||
+-- BytesWarning | |||
+-- ResourceWarning |
Latest revision as of 08:39, 30 December 2020
Ciao,
I am Orso, an Italian Vectorscripter since many years. Some of you might know me from Vectorlab or the comments on the present Developer wiki. I feel very comfortable with Vectorscript but will now switch over to Python for even more power. I will try to share here comments, problems -and solutions- from the point of view of a non-programmer. --Orso.b.schmid (talk) 08:13, 17 May 2015 (EDT)
If you add comments, please use the full wiki formatting, easily available clicking on Advanced while on edit mode and don't forget to sign up your comment using --~~~~!
Vectorlab Archives
Here is the List Browsers article from the now dead Vectorlab site:
- List Browsers ( Vectorlab ListBrowsers Web Archives.zip)
I stored some of the Vectorlab sites:
VS - Py Rosetta Stone
Description | Vectorscript | Python |
---|---|---|
Statement ending: | Semicolon always needed
|
Semicolon needed only for multiple statements on one line:
Error Message: SyntaxError: invalid syntax |
Case sensitivity | Not case sensitive:
|
Case sensitive:
Error Message: AttributeError: 'module' object has no attribute 'vs.ALRTDIALOG' |
Empty brakes for functions
|
Can be without brakets
|
Can't be without brakets
Error Message: - none! be careful! - |
Empty handles
|
|
|
Variable scope
|
Global wins over local:
{ GLOBAL ACCESS } { parent of subroutine "Increment" } PROCEDURE Main; VAR { good praxis: label globals with "g" } gIndex, gNum : INTEGER; { subroutine } PROCEDURE Increment; BEGIN { gNum is not defined in this subroutine the parser climbs up parent containers until it finds a declaration for the var gNum. In this case it can be found in Main } gNum := gNum +1; SysBeep; END; BEGIN gNum := 10; { init } FOR gIndex := 1 TO 10 DO Increment; { increments the variable gNum } AlrtDialog(Concat(gNum)); { returns 20 } END; Run(Main); |
Local wins over global:
# LOCAL ACCESS # subroutine def Increment(): # gNum is not defined in this subroutine # the parser creates a local instance of the var gNum! gNum +=1 vs.SysBeep gNum = 10 # init for gIndex in range(1, 10): Increment # increments the variable gNum # but only inside Increment! vs.AlrtDialog(str(gNum)) # returns 10! The global var didn't set # GLOBAL ACCESS: CORRECT # subroutine def Increment(): # gNum is not defined in this subroutine # tell the parser that you want to edit gNum global! global gNum gNum +=1 vs.SysBeep() gNum = 10 # init # please observe that the range is NOT 1, 10! for gIndex in range(0, 10): Increment() # increments the variable gNum # but only inside Increment! vs.AlrtDialog(str(gNum)) # returns 20 # GLOBAL ACCESS: WRONG # subroutine def Increment(): # gNum is not defined in this subroutine # tell the parser that you want to edit gNum global! global gNum gNum +=1 vs.SysBeep() # no init! for gIndex in range(0, 10): Increment() # increments the variable gNum # but only inside Increment! vs.AlrtDialog(str(gNum)) # rises error Error Message: NameError: global name 'gNum' is not defined |
FOR statements | Runs including last value:
{ runs 3 times! 1, 2 and 3 } FOR i := 1 TO 3 DO AlrtDialog(Concat(i)); |
Runs excluding last value:
# runs 2 times! 1 and 2 for i in range(1, 3): vs.AlrtDialog(str(i)) |
Colors |
|
Warning: don't forget the brakets:
Error Message: - none! be careful! - |
Concatenate text | Supports implicit conversion:
|
Doesn't support implicit conversion:
Error Message: TypeError: unsupported operand type(s) for +: 'int' and 'str' |
Encryption | Whatever .vs or .px file is linked through your includes, will be encrypted upon running the encrypt command. More infos here. | Create list of your included files in an xml file. Please read Vlado on Techboard |
Python version | import sys
| |
"import vs" | import vs # do I need this?
| |
Caching
|
varPersistentPythonEngine = 412 { Boolean }
In the SDK starting from VW 2014 we can read: When True the Python engine is the same for the execution of all scripts, this solves some issues with Py_Initialize and Py_Finalize. For example, when debugging externally python leaves threas that cause crash if Py_Initialize and Py_Finalize is used for each script call. So, this allows the engine to be preserved between calls, however Vectorworks will delete all custom modules and objects defined in the engine prior each execution. |
Lists
Lists are powerful in Python, below some fascinating lists manipulations. They remind me of Applescript:
months = "Jan Feb Mar Apr May Jun Jul" months = months.split() # no splitter defined and it will use the empty space --> ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul'] months[2] # --> 'Mar' note that the index is 0-based months2 = "Jan, Feb, Mar, Apr, May, Jun, Jul" months2.split(', ') # --> ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul'] use comma and empty space as splitter months.append('Jul') # --> ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul'] append adds an item to a list months.pop() #- -> 'Jul' pop fetches the last item of a list ', sunny '.join(months) # --> ', sunny Jan, sunny Feb, sunny Mar, sunny Apr, sunny May, sunny Jun, sunny Sep' '-'.join(months[1:3]) # --> 'Feb-Mar' del months[2] # --> ['Jan', 'Feb', 'Apr', 'May', 'Jun', 'Jul'] months = {1: 'Jan', 2: 'Feb', 3: 'Mar'} # --> {1: 'Jan', 2: 'Feb', 3: 'Mar'}
Errors
Python Error Messages: https://docs.python.org/3/library/exceptions.html
BaseExceptions:
+-- SystemExit +-- KeyboardInterrupt +-- GeneratorExit +-- Exception +-- StopIteration +-- ArithmeticError | +-- FloatingPointError | +-- OverflowError | +-- ZeroDivisionError +-- AssertionError +-- AttributeError +-- BufferError +-- EOFError +-- ImportError +-- LookupError | +-- IndexError | +-- KeyError +-- MemoryError +-- NameError | +-- UnboundLocalError +-- OSError | +-- BlockingIOError | +-- ChildProcessError | +-- ConnectionError | | +-- BrokenPipeError | | +-- ConnectionAbortedError | | +-- ConnectionRefusedError | | +-- ConnectionResetError | +-- FileExistsError | +-- FileNotFoundError | +-- InterruptedError | +-- IsADirectoryError | +-- NotADirectoryError | +-- PermissionError | +-- ProcessLookupError | +-- TimeoutError +-- ReferenceError +-- RuntimeError | +-- NotImplementedError +-- SyntaxError | +-- IndentationError | +-- TabError +-- SystemError +-- TypeError +-- ValueError | +-- UnicodeError | +-- UnicodeDecodeError | +-- UnicodeEncodeError | +-- UnicodeTranslateError +-- Warning +-- DeprecationWarning +-- PendingDeprecationWarning +-- RuntimeWarning +-- SyntaxWarning +-- UserWarning +-- FutureWarning +-- ImportWarning +-- UnicodeWarning +-- BytesWarning +-- ResourceWarning