Miscellaneous Notes

Miscellaneous Notes#

Fundamentals
Data Structure
Program Structure
Input and Output
Classes and Objects

## How to check current object sizes in Notebook
import sys
a = range(10000)
print(sys.getsizeof(a))

## Get the docstring
?sys.getsizeof
?who

%who
%whos

globals()

{'__name__': '__main__',
 '__doc__': 'Automatically created module for IPython interactive environment',
 '__package__': None,
 '__loader__': None,
 '__spec__': None,
 '__builtin__': <module 'builtins' (built-in)>,
 '__builtins__': <module 'builtins' (built-in)>,
 '_ih': ['',
  "#import sys\na = range(10000)\n#%memusage a\nget_ipython().run_line_magic('who', '')\nget_ipython().run_line_magic('whos', '')",
  "#import sys\na = range(10000)\n#%memusage a\nget_ipython().run_line_magic('who', '')\nget_ipython().run_line_magic('whos', '')",
  "#import sys\na = range(10000)\n#%memusage a\nget_ipython().run_line_magic('who', '')\nget_ipython().run_line_magic('whos', '')\nglobal()",
  "#import sys\na = range(10000)\n#%memusage a\nget_ipython().run_line_magic('who', '')\nget_ipython().run_line_magic('whos', '')\nglobals()",
  "#import sys\na = range(10000)\n#%memusage a\nget_ipython().run_line_magic('who', '')\nget_ipython().run_line_magic('whos', '')\nglobals()\nlocals()",
  'globals()'],
 '_oh': {4: {...}, 5: {...}},
 '_dh': ['/Users/Alvin/Dropbox/Python/PythonTricksTheBook/PythonTricksJupyterBook'],
 'In': ['',
  "#import sys\na = range(10000)\n#%memusage a\nget_ipython().run_line_magic('who', '')\nget_ipython().run_line_magic('whos', '')",
  "#import sys\na = range(10000)\n#%memusage a\nget_ipython().run_line_magic('who', '')\nget_ipython().run_line_magic('whos', '')",
  "#import sys\na = range(10000)\n#%memusage a\nget_ipython().run_line_magic('who', '')\nget_ipython().run_line_magic('whos', '')\nglobal()",
  "#import sys\na = range(10000)\n#%memusage a\nget_ipython().run_line_magic('who', '')\nget_ipython().run_line_magic('whos', '')\nglobals()",
  "#import sys\na = range(10000)\n#%memusage a\nget_ipython().run_line_magic('who', '')\nget_ipython().run_line_magic('whos', '')\nglobals()\nlocals()",
  'globals()'],
 'Out': {4: {...}, 5: {...}},
 'get_ipython': <bound method InteractiveShell.get_ipython of <ipykernel.zmqshell.ZMQInteractiveShell object at 0x7ff579662588>>,
 'exit': <IPython.core.autocall.ZMQExitAutocall at 0x7ff57969aa20>,
 'quit': <IPython.core.autocall.ZMQExitAutocall at 0x7ff57969aa20>,
 '_': {...},
 '__': {...},
 '___': '',
 '_i': '#import sys\na = range(10000)\n#%memusage a\n%who\n%whos\nglobals()\nlocals()',
 '_ii': '#import sys\na = range(10000)\n#%memusage a\n%who\n%whos\nglobals()',
 '_iii': '#import sys\na = range(10000)\n#%memusage a\n%who\n%whos\nglobal()',
 '_i1': '#import sys\na = range(10000)\n#%memusage a\n%who\n%whos',
 'a': range(0, 10000),
 '_i2': '#import sys\na = range(10000)\n#%memusage a\n%who\n%whos',
 '_i3': '#import sys\na = range(10000)\n#%memusage a\n%who\n%whos\nglobal()',
 '_i4': '#import sys\na = range(10000)\n#%memusage a\n%who\n%whos\nglobals()',
 '_4': {...},
 '_i5': '#import sys\na = range(10000)\n#%memusage a\n%who\n%whos\nglobals()\nlocals()',
 '_5': {...},
 '_i6': 'globals()'}

locals()

{'__name__': '__main__',
 '__doc__': 'Automatically created module for IPython interactive environment',
 '__package__': None,
 '__loader__': None,
 '__spec__': None,
 '__builtin__': <module 'builtins' (built-in)>,
 '__builtins__': <module 'builtins' (built-in)>,
 '_ih': ['',
  "#import sys\na = range(10000)\n#%memusage a\nget_ipython().run_line_magic('who', '')\nget_ipython().run_line_magic('whos', '')",
  "#import sys\na = range(10000)\n#%memusage a\nget_ipython().run_line_magic('who', '')\nget_ipython().run_line_magic('whos', '')",
  "#import sys\na = range(10000)\n#%memusage a\nget_ipython().run_line_magic('who', '')\nget_ipython().run_line_magic('whos', '')\nglobal()",
  "#import sys\na = range(10000)\n#%memusage a\nget_ipython().run_line_magic('who', '')\nget_ipython().run_line_magic('whos', '')\nglobals()",
  "#import sys\na = range(10000)\n#%memusage a\nget_ipython().run_line_magic('who', '')\nget_ipython().run_line_magic('whos', '')\nglobals()\nlocals()",
  'globals()',
  'locals()',
  'locals()'],
 '_oh': {4: {...}, 5: {...}, 6: {...}, 7: {...}},
 '_dh': ['/Users/Alvin/Dropbox/Python/PythonTricksTheBook/PythonTricksJupyterBook'],
 'In': ['',
  "#import sys\na = range(10000)\n#%memusage a\nget_ipython().run_line_magic('who', '')\nget_ipython().run_line_magic('whos', '')",
  "#import sys\na = range(10000)\n#%memusage a\nget_ipython().run_line_magic('who', '')\nget_ipython().run_line_magic('whos', '')",
  "#import sys\na = range(10000)\n#%memusage a\nget_ipython().run_line_magic('who', '')\nget_ipython().run_line_magic('whos', '')\nglobal()",
  "#import sys\na = range(10000)\n#%memusage a\nget_ipython().run_line_magic('who', '')\nget_ipython().run_line_magic('whos', '')\nglobals()",
  "#import sys\na = range(10000)\n#%memusage a\nget_ipython().run_line_magic('who', '')\nget_ipython().run_line_magic('whos', '')\nglobals()\nlocals()",
  'globals()',
  'locals()',
  'locals()'],
 'Out': {4: {...}, 5: {...}, 6: {...}, 7: {...}},
 'get_ipython': <bound method InteractiveShell.get_ipython of <ipykernel.zmqshell.ZMQInteractiveShell object at 0x7ff579662588>>,
 'exit': <IPython.core.autocall.ZMQExitAutocall at 0x7ff57969aa20>,
 'quit': <IPython.core.autocall.ZMQExitAutocall at 0x7ff57969aa20>,
 '_': {...},
 '__': {...},
 '___': {...},
 '_i': 'locals()',
 '_ii': 'globals()',
 '_iii': '#import sys\na = range(10000)\n#%memusage a\n%who\n%whos\nglobals()\nlocals()',
 '_i1': '#import sys\na = range(10000)\n#%memusage a\n%who\n%whos',
 'a': range(0, 10000),
 '_i2': '#import sys\na = range(10000)\n#%memusage a\n%who\n%whos',
 '_i3': '#import sys\na = range(10000)\n#%memusage a\n%who\n%whos\nglobal()',
 '_i4': '#import sys\na = range(10000)\n#%memusage a\n%who\n%whos\nglobals()',
 '_4': {...},
 '_i5': '#import sys\na = range(10000)\n#%memusage a\n%who\n%whos\nglobals()\nlocals()',
 '_5': {...},
 '_i6': 'globals()',
 '_6': {...},
 '_i7': 'locals()',
 '_7': {...},
 '_i8': 'locals()'}

dir()

['In',
 'Out',
 '_',
 '_4',
 '_5',
 '_6',
 '_7',
 '_8',
 '__',
 '___',
 '__builtin__',
 '__builtins__',
 '__doc__',
 '__loader__',
 '__name__',
 '__package__',
 '__spec__',
 '_dh',
 '_i',
 '_i1',
 '_i2',
 '_i3',
 '_i4',
 '_i5',
 '_i6',
 '_i7',
 '_i8',
 '_i9',
 '_ih',
 '_ii',
 '_iii',
 '_oh',
 'a',
 'exit',
 'get_ipython',
 'quit']