Page History
...
| Code Block |
|---|
s = ' '.join(sys.argv) |
Join path and name
| Code Block |
|---|
path_name = os.path.join(path,fname) |
...
| Code Block |
|---|
exp = 'xpptut13' if 'tut' is in exp : <do something> |
...
String alignment
| Code Block |
|---|
msg = '%s' % (k.ljust(16)) |
...
Useful string parsing options
...
| Code Block |
|---|
my_string.replace("abcde","cde")
|
...
String formatting
| Code Block |
|---|
s = 'some text %s %s' % (msg.ljust(30), str(val).rjust(30) |
...
| Code Block |
|---|
sys._getframe().f_code.co_name |
Function parameters
| Code Block |
|---|
locals() # returns (dict) of method input parameters |
Converting integer to bin(), oct(), hex() string
...
| Code Block |
|---|
from time import localtime, gmtime, strftime, clock, time
time_sec = time() # epoch time
def get_current_local_time_stamp(fmt='%Y-%m-%d %H:%M:%S %Z'):
return strftime(fmt, localtime())
def get_current_gm_time_stamp(fmt='%Y-%m-%d %H:%M:%S %Z'):
return strftime(fmt, gmtime())
def get_local_time_str(time_sec, fmt='%Y-%m-%d %H:%M:%S %Z'):
return strftime(fmt, localtime(time_sec))
def get_gm_time_str(time_sec, fmt='%Y-%m-%d %H:%M:%S %Z'):
return strftime(fmt, gmtime(time_sec)) |
...
Set PYTHONPATH
In command-line:
...
| Code Block |
|---|
import os
os.environ['PYTHONPATH'] = '/reg/neh/home1/dubrovin/LCLS/git-work/pyapps:%s' % os.environ.get('PYTHONPATH', '') |
...
Replace symbols in string
| Code Block |
|---|
text.replace("|",":").replace("-",".")
range.replace('9999','end')
msg.replace('\n',' ') |
...
List of comprehension
list_of_x2 = [x*x for x in list_of_x]
...
| Code Block |
|---|
def f(x,y) :
return x if y>0 else -x
list = map(f, arrX, arrY) |
...
Constructor, destructor etc.
| Code Block |
|---|
class PeakListFile :
def __init__(self, fname) :
print 'constructor'
self.f=open(fname,'r')
def __del__(self) :
print 'destructor'
try :
self.f.close()
def __call__(self) :
print 'this is a default method of this object called as obj()' |
...
Polymorphism
Derived class initialization
| Code Block |
|---|
class Base :
def __init__(self) :
...
class Derived(Base) :
def __init__(self) :
Base.__init__(self)
# OR
super(Derived, self).__init__() |
...
Create/save temporary file
...
| Code Block |
|---|
import sys
def test_all() :
print _sep_, '\n%s' % sys._getframe().f_code.co_name
test_ricker()
test_morlet()
#------------------------------
if __name__ == "__main__" :
from time import time
tname = sys.argv[1] if len(sys.argv) > 1 else '0'
print 50*'_', '\nTest %s:' % tname
t0_sec = time()
if tname == '0': test_all()
elif tname == '1': test_ricker()
elif tname == '2': test_morlet()
else : print 'Not-recognized test name: %s' % tname
msg = 'End of test %s, consumed time (sec) = %.6f' % (tname, time()-t0_sec)
sys.exit(msg) |
...
Virtualenv
| Code Block |
|---|
virtualenv dir-name source <directoryName>/bin/activate.csh # for tcsh # or source <directoryName>/bin/activate # for bash pip install <packageName> ... work deactivate |
...
Python - useful references
...
Built-in functions
http://docs.python.org/library/functions.html
...
http://docs.python.org/library/functions.html#setattr
PyQt4
Know How
- QGraphicsScene item priority is set by setZValue(v)
- All re-implemented Event methods like {{mouseMoveEvent(self, e)}} etc. in items will get control only if QGraphicsView their default version will be called.
...
Overview
Content Tools