...
Code Block |
---|
try :
plf = PeakListFile(fname)
except Exception as e:
print 'We cought exception: %s' % e |
Manipulation with directories and files
...
User defined exception
Code Block |
---|
defclass getListOfFilesInDirMyError(dirnameException) :
return os.listdir(dirname)
def printListOfFilesInDir(dirname) def __init__(self, value):
print 'List of files inself.value the dir.', dirname= value
for name in os.listdir(dirname) def __str__(self):
print namereturn repr(self.value)
...
try:
print '\n'
|
Parsing the pathname
Code Block |
---|
raise MyError(2*2)
except MyError as e:
print 'My exception rootoccurred, extvalue:', e.value |
Manipulation with directories and files
Access to files in the derectory
Code Block |
---|
def getListOfFilesInDir(dirname) : = os.path.splitext(path) # i.e. path='root-part.tail-part'
basename =return os.path.basenamelistdir(pathdirname)
def printListOfFilesInDir(dirname) :
print 'List dirnameof files in =the os.path.dirname(path)dir.', dirname
for name lexist = in os.path.lexistslistdir(pathdirname) :
isfile = os.path.isfile(path)print name
print '\n'
|
Parsing the pathname
Code Block |
---|
path = isdir '/reg/d/psdm/cxi/cxif5315/calib/pnccd/pnccd-123456.data'
root, ext = os.path.isdirsplitext(path)
head, tail= os.path.split(path) # i.e. path='head-part/tail-part'
...
|
http://docs.python.org/library/os.path.html
Joint path and name
Code Block |
---|
path_name # ('/reg/d/psdm/cxi/cxif5315/calib/pnccd/pnccd-123456', '.data') # or '' if something is missing
basename = os.path.basename(path) # pnccd-123456.data
dirname = os.path.joindirname(path,fname)
|
Check if string contains pattern
Code Block |
---|
exp = 'xpptut13'
if 'tut' is in exp : <do something> |
Useful string parsing options
http://docs.python.org/library/string.html
Code Block |
---|
string.rsplit(str, sep, maxsplit)
string.capitalize(word)
string.lower(s)
start = string.find(symbolic_string, pattern)
pattern_length = len(pattern)
|
http://docs.python.org/library/parser.html?
) # /reg/d/psdm/cxi/cxif5315/calib/pnccd
lexist = os.path.lexists(path) # False
isfile = os.path.isfile(path) # False
isdir = os.path.isdir(path) # False
head, tail= os.path.split(path) # ('/reg/d/psdm/cxi/cxif5315/calib/pnccd', 'pnccd-123456.data') # or '' if something is missing
...
|
Or use more shorter methods for str
object:
http://docs.python.org/library/stdtypesos.path.html, for example:
Join list of strings
Code Block |
---|
par_strs = line[pos_eq+1:].strip(' ').rstrip('\n')
|
...
Join path and name
Code Block |
---|
my_string.replace("abcde","cde")
|
String formatting
Code Block |
---|
s = 'some text %s %s' % (msg.ljust(30), str(val).rjust(30)
|
List of comprehension
list_of_x2 = [x*x for x in list_of_x]
list_of_x_selected = [x for x,y in zip(list_of_x, list_of_y) if y>0]
map - built-in method
Code Block |
---|
def f(x,y) :
return x if y>0 else -x
list = map(f, arrX, arrY) |
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__() |
Python - useful references
Built-in functions
http://docs.python.org/library/functions.html
setattr - gives dynamic variables in python
http://docs.python.org/library/functions.html#setattr
PyQt4
PyQt4 class references
All classes
Selected:
Open/close/move other GUI window
Try to close window if its object exists, othervise - open:
path_name = os.path.join(path,fname)
|
Check if string contains pattern
Code Block |
---|
exp = 'xpptut13'
if 'tut' is in exp : <do something> |
String alignment
Code Block |
---|
msg = '%s' % (k.ljust(16)) |
Useful string parsing options
http://docs.python.org/library/string.html
Code Block |
---|
string.rsplit(str, sep, maxsplit)
string.capitalize(word)
string.lower(s)
start = string.find(symbolic_string, pattern)
pattern_length = len(pattern)
|
http://docs.python.org/library/parser.html?
Or use more shorter methods for str
object:
http://docs.python.org/library/stdtypes.html, for example:
Code Block |
---|
par_str = line[pos_eq+1:].strip(' ').rstrip('\n')
|
Replace the part of the string
Code Block |
---|
my_string.replace("abcde","cde")
|
String formatting
Code Block |
---|
s = 'some text %s %s' % (msg.ljust(30), str(val).rjust(30)
|
Class string properties
Code Block |
---|
print 'string properties:'
print 'punctuation : ', string.punctuation
print 'digits : ', string.digits
print 'octdigits : ', string.octdigits
print 'hexdigits : ', string.hexdigits
print 'ascii_letters : ', string.ascii_letters
print 'ascii_lowercase: ', string.ascii_lowercase
print 'ascii_uppercase: ', string.ascii_uppercase
print 'lowercase : ', string.lowercase
print 'uppercase : ', string.uppercase
print 'letters |
Code Block |
---|
def processConfigPars(self):
print 'processConfigPars'
try :
cp.confpars.guiconfigparameters.close()
except : # AttributeError: #NameError
cp.confpars.guiconfigparameters = guiconfigpars.GUIConfigParameters()
cp.confpars.guiconfigparameters.move(self.pos().__add__(QtCore.QPoint(100,330))) # window offset
# or use self.parentWidget().pos() for combined widgets:
: #', cp.guifilebrowser.move(self.parentWidget().pos().__add__(QtCore.QPoint(240,40)))string.letters
print 'printable : cp.confpars.guiconfigparameters.show()
|
Note |
---|
Sometime it looks like the window does not want to move in specified position... In particular I have observed, that everything is going correct untill the w.show() . then, suddenly happens moveEvent(), which changes the self.pos(). In my case it happened because at construction of the combined window, its size was changed and it was moved in origin... Reservation of larger window size solved this problem. |
Close window and delete object
Code Block |
---|
def closeEvent(self, event):
try: # try to delete self object in the cp.confpars
del cp.confpars.guiconfigparameters
except # AttributeError:
pass # silently ignore
|
Change style of buttons depending on status
For particular QPushButton it works:
Code Block |
---|
self.but_path = QtGui.QPushButton('File:')
self.but_path.setObjectName('but_path')
self.but_path.setStyleSheet('QPushButton#but_path:pressed {color: black; background-color: green;}' +
'QPushButton#but_path:disabled {color: white; background-color: pink;}' +
'QPushButton {color: blue; background-color: yellow;}')
|
For entire application it should be like:
Code Block |
---|
app = QtGui.QApplication.instance()
app.setStyleSheet('QLabel{color: #fff;} QPushButton{background-color: #000; color: #fff}')
|
but does not work for me...
Make window visible on the top
Scroll down text in
Assuming
Code Block |
---|
self.box_txt = QtGui.QTextEdit()
self.box_txt.setText('some text')
self.box_txt.append('a lot of additional text, exceeding the window size')
self.box_txt.ensureCursorVisible()
|
Scroll bar can be used, but result is not seen imidiately:
Code Block |
---|
scrol_bar_v = self.box_txt.verticalScrollBar() # QScrollBar
scrol_bar_v.setValue(scrol_bar_v.maximum())
|
Moving text cursor with repaint() works immidiately:
Code Block |
---|
self.box_txt.moveCursor(QtGui.QTextCursor.End)
self.box_txt.repaint()
|
Set optimal table-widget size
Code Block |
---|
self.table = QtGui.QTableWidget(rows, cols, self)
...
self.table.setFixedWidth(self.table.horizontalHeader().length() + 4)
self.table.setFixedHeight(self.table.verticalHeader().length() + 29)
|
Show image in QLabel
Assumes:
', string.printable
print 'whitespace : ', string.whitespace |
Class name
Code Block |
---|
self.__class__.__name__ |
Function name
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
using built-in functions
Code Block |
---|
ival = 123456
str_bin = bin(ival)
str_oct = oct(ival)
str_hex = hex(ival) |
Time stamp
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 |
---|
setenv PYTHONPATH /reg/neh/home1/dubrovin/LCLS/git-work/pyapps:${PYTHONPATH} |
In cshell script:
Code Block |
---|
alias setpp 'setenv PYTHONPATH /reg/neh/home1/dubrovin/LCLS/git-work/pyapps:${PYTHONPATH}' |
In code:
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]
list_of_x_selected = [x for x,y in zip(list_of_x, list_of_y) if y>0]
map - built-in method
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 |
Code Block |
---|
class GUIImage ( QtGui.QLabel ) :
def __init__ (self, parent=None, app=None) :
QtGui..QLabel.__init__(self, parent)
class self.setGeometry(200, 100, 100, 100)Derived(Base) :
self.setWindowTitle('Image For Grabber')
def __init__(self) :
self.setFrame(Base.__init__(self)
...
|
i.e. self
is an instance of QLabel
.
Set pixmap for image
Code Block |
---|
def setPixmapForImage(self):
# OR
super(Derived, if self).r_pixmap == None :
self.s_pixmap = None
self.clear()
else :
self.s_pixmap = self.r_pixmap.scaled(self.size(), QtCore.Qt.KeepAspectRatio)
self.setPixmap(self.s_pixmap)
self.setAlignment(QtCore.Qt.AlignTop | QtCore.Qt.AlignLeft)
self.setScailedMask()
|
Grab image from monitor
...
Create/save temporary file
Code Block |
---|
import tempfile
tmp_file = tempfile.NamedTemporaryFile(mode='r+b',suffix='.tiff')
tfile = tmp_file.name |
Good example of __main__
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
setattr, getattr - set/get dynamic variables in python
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.
PyQt4 class references
All classes
Selected:
Open/close/move other GUI window
Try to close window if its object exists, othervise - open:
Code Block |
---|
def processConfigPars(self):
print 'processConfigPars'
try :
cp.confpars.guiconfigparameters.close()
except : # AttributeError: #NameError
cp.confpars.guiconfigparameters = guiconfigpars.GUIConfigParameters()
cp.confpars.guiconfigparameters.move(self.pos().__add__(QtCore.QPoint(100,330))) # window offset
# or use self.parentWidget().pos() for combined widgets:
# cp.guifilebrowser.move(self.parentWidget().pos().__add__(QtCore.QPoint(240,40)))
cp.confpars.guiconfigparameters.show()
|
Note |
---|
Sometime it looks like the window does not want to move in specified position... In particular I have observed, that everything is going correct untill the w.show() . then, suddenly happens moveEvent(), which changes the self.pos(). In my case it happened because at construction of the combined window, its size was changed and it was moved in origin... Reservation of larger window size solved this problem. |
Close window and delete object
Code Block |
---|
def closeEvent(self, event):
try: # try to delete self object in the cp.confpars
del cp.confpars.guiconfigparameters
except # AttributeError:
pass # silently ignore
|
Change style of buttons depending on status
For particular QPushButton it works:
Code Block |
---|
self.but_path = QtGui.QPushButton('File:')
self.but_path.setObjectName('but_path')
self.but_path.setStyleSheet('QPushButton#but_path:pressed {color: black; background-color: green;}' +
'QPushButton#but_path:disabled {color: white; background-color: pink;}' +
'QPushButton {color: blue; background-color: yellow;}')
|
For entire application it should be like:
Code Block |
---|
app = QtGui.QApplication.instance()
app.setStyleSheet('QLabel{color: #fff;} QPushButton{background-color: #000; color: #fff}')
|
but does not work for me...
Make window visible on the top
Scroll down text in
Assuming
Code Block |
---|
self.box_txt = QtGui.QTextEdit()
self.box_txt.setText('some text')
self.box_txt.append('a lot of additional text, exceeding the window size')
self.box_txt.ensureCursorVisible()
|
Scroll bar can be used, but result is not seen imidiately:
Code Block |
---|
scrol_bar_v = self.box_txt.verticalScrollBar() # QScrollBar
scrol_bar_v.setValue(scrol_bar_v.maximum())
|
Moving text cursor with repaint() works immidiately:
Code Block |
---|
self.box_txt.moveCursor(QtGui.QTextCursor.End)
self.box_txt.repaint()
|
Set optimal table-widget size
Code Block |
---|
self.table = QtGui.QTableWidget(rows, cols, self)
...
self.table.setFixedWidth(self.table.horizontalHeader().length() + 4)
self.table.setFixedHeight(self.table.verticalHeader().length() + 29)
|
Show image in QLabel
Assumes:
Code Block |
---|
class GUIImage ( QtGui.QLabel ) :
def __init__ (self, parent=None, app=None) :
QtGui.QLabel.__init__(self, parent)
self.setGeometry(200, 100, 100, 100)
self.setWindowTitle('Image For Grabber')
self.setFrame()
...
|
i.e. self
is an instance of QLabel
.
Set pixmap for image
Code Block |
---|
def setPixmapForImage(self):
if self.r_pixmap == None :
self.s_pixmap = None
self.clear()
else :
self.s_pixmap = self.r_pixmap.scaled(self.size(), QtCore.Qt.KeepAspectRatio)
self.setPixmap(self.s_pixmap)
self.setAlignment(QtCore.Qt.AlignTop | QtCore.Qt.AlignLeft)
self.setScailedMask()
|
Grab image from monitor
Code Block |
---|
import tempfile
def grabImage(self):
fname = tempfile.NamedTemporaryFile(mode='r+b',suffix='.ppm')
if( 0 == os.system('import -trim -frame -border %s' % (fname.name))) :
self.r_pixmap = QtGui.QPixmap(QtGui.QImage(fname.name,'.ppm'))
self.setPixmapForImage()
|
Supported in QImage formats:
Format | Description | Qt's support |
---|
BMP | Windows Bitmap | Read/write |
GIF | Graphic Interchange Format (optional) | Read |
JPG | Joint Photographic Experts Group | Read/write |
JPEG | Joint Photographic Experts Group | Read/write |
PNG | Portable Network Graphics | Read/write |
PBM | Portable Bitmap | Read |
PGM | Portable Graymap | Read |
PPM | Portable Pixmap | Read/write |
TIFF | Tagged Image File Format | Read/write |
XBM | X11 Bitmap | Read/write |
XPM | X11 Pixmap | Read/write |
Grab entire monitor window
...
When QPushButton is pressed and connected method is called, all button properties stay unchanged until the method. In order to see current changes one has to repaint widget. For example:. In order to see current changes one has to repaint widget. For example:
Code Block |
---|
self.but_elog.setStyleSheet(cp.styleButton)
self.but_elog.setEnabled(False)
self.repaint() |
Dialog boxes
For password
Code Block |
---|
app = QtGui.QApplication(sys.argv)
w = QtGui.QInputDialog()
w.show()
msg = 'To use %s and submitt messages in ELog\nauthentication for user %s is required\nPassword:' % (sys.argv[0], opts.usr)
text, ok = w.getText(None, 'Authentication', msg, QtGui.QLineEdit.Password)
w.close()
... |
Code Block |
---|
self.but_elog.setStyleSheet(cp.styleButton)
self.but_elog.setEnabled(False)
self.repaint() |
Graphics in PyQt4
Code Block |
---|
...
self.poi1 = QtCore.QPoint(0,0)
self.poi2 = QtCore.QPoint(0,0)
self.rect1 = QtCore.QRect()
self.rect2 = QtCore.QRect()
self.pen1 = QtGui.QPen(QtCore.Qt.black)
self.pen2 = QtGui.QPen(QtCore.Qt.white)
self.pen1.setStyle(QtCore.Qt.DashLine)
self.pen2.setStyle(QtCore.Qt.DashLine)
self.pen1.setWidthF(1)
self.pen2.setWidthF(1)
...
def paintEvent(self, e):
super(GUIImage,self).paintEvent(e)
qp = QtGui.QPainter()
# or QPainter can be defined earlier and use it as qp = self.qp
qp.begin(self)
#self.drawPixmap(qp)
self.drawRect(qp)
qp.end()
self.update()
def setPen(self, qp):
self.pen.setStyle(QtCore.Qt.DashLine)
self.pen.setWidthF(1)
def drawRect(self, qp):
if self.r_pixmap == None:
return
p1x, p1y = self.poi1.x(), self.poi1.y()
p2x, p2y = self.poi2.x(), self.poi2.y()
R=1
if abs(p2x-p1x) < R : return
if abs(p2y-p1y) < R : return
self.rect1.setCoords( p1x, p1y, p2x, p2y)
self.rect2.setCoords( p1x+1, p1y+1, p2x-1, p2y-1)
qp.setPen (self.pen1)
qp.drawRect(self.rect1);
qp.setPen (self.pen2)
qp.drawRect(self.rect2);
def drawPixmap(self, qp):
if self.r_pixmap != None:
qp.drawPixmap(0,0,self.s_pixmap)
|
...
Graphic
Code Block |
---|
import pyimgalgos.Graphics as gr
axes.clear()
axes.plot(xarr1, yarr1, '-r', xarr2, yarr2, '-g')
gr.show(mode='do_not_hold') |
Histogram
Code Block |
---|
axes.clear()
axes.hist(arr, bins=100, range=(10,50), log=False) # log for vertical scale only
|
Image (with colorbar)
Code Block |
---|
img = axes.imshow(arr2d, interpolation='nearest', origin='bottom', aspect='auto')
img.set_clim(Amin,Amax)
cbar = self.fig.colorbar(img, orientation='vertical', \
fraction=0.1, pad=0.01, shrink=1.0, aspect=20)
# fraction - of the 2d plot occupied by the color bar
# pad - is a space between 2d image and color bar
# shrink - factor for the length of the color bar
# aspect - ratio length/width of the color bar
|
...
Other supported formats: gif, pdf, png, jpeg, eps
eps
Check tiff file
To check tiff file format one may use command:
% identify -verbose <file-name>.tiff
Save image in 16-bit TIFF file
...
Code Block |
---|
V = np.array(...)
Vmin, Vmax, Nbins1 <--- scalar valuer
indarr, Vmax, Nbins1 <--- scalar valuer
indarr = np.int32( factor * (V-Vmin) )
arr = np.select([V==Vmax, indarr<0, indarr>Nbins1], [Nbins1, 0, 0], default=indarr) |
protected division:
Code Block |
---|
def divideZeroProteced(nda_num, nda_den, val_subst_zero=0) :
pro_num = np.int32( factor * (V-Vmin) )
arrselect([nda_den==0], [val_subst_zero], default=nda_num)
pro_den = np.select([Vnda_den==Vmax0], indarr<0, indarr>Nbins1], [Nbins1, 0, 0], default=indarr)[1], default=nda_den)
return pro_num / pro_den |
SciPy
Import
Code Block |
---|
#!/usr/bin/env python
import numpy as np
from scipy.optimize import curve_fit
|
...