[Tutor] First steps with Tkinter
Hi! Just started trying to get to grips with Python and Tkinter. Have Frederick Lundh's tutorial and am on program hello2.py which looks like this # File: hello2.py from Tkinter import * class App: def __init__(self, master): frame = Frame(master) frame.pack() self.button = Button(frame, text="QUIT", fg="red", command=frame.quit) self.button.pack(side=LEFT) self.hi_there = Button(frame, text="Hello", command=self.say_hi) self.hi_there.pack(side=LEFT) def say_hi(self): print "hi there, everyone!" root = Tk() app = App(root) root.mainloop() I am running from inside Pythonwin 2.4 IDE under XP Pro and every time I run hello2.py it freezes when I press "QUIT". The only way to kill it is through Alt-Ctrl-Del but this crashes Pythonwin. Any workaround for this so that I can use Tkinter from inside the IDE? BTW the same thing happend with IDLE Thanks in advance Alun Griffiths ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] First steps with Tkinter
Catherine I'm a Python newbie too but have done some programming with C++ Builder so have a little knowledge of GUIs etc Best regards Alun At 22:41 26/01/2006, catherine curley wrote: Alan As a matter of interest, did you have much knowledge of Python before you tried TKinter? I'm only a python beginner at present. Catherine On 1/26/06, [EMAIL PROTECTED] <[EMAIL PROTECTED] > wrote: Hi! Just started trying to get to grips with Python and Tkinter. Have Frederick Lundh's tutorial and am on program hello2.py which looks like this # File: hello2.py from Tkinter import * class App: def __init__(self, master): frame = Frame(master) frame.pack() self.button = Button(frame, text="QUIT", fg="red", command=frame.quit) self.button.pack(side=LEFT) self.hi_there = Button(frame, text="Hello", command=self.say_hi) self.hi_there.pack (side=LEFT) def say_hi(self): print "hi there, everyone!" root = Tk() app = App(root) root.mainloop() I am running from inside Pythonwin 2.4 IDE under XP Pro and every time I run hello2.py it freezes when I press "QUIT". The only way to kill it is through Alt-Ctrl-Del but this crashes Pythonwin. Any workaround for this so that I can use Tkinter from inside the IDE? BTW the same thing happend with IDLE Thanks in advance Alun Griffiths ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] Looping over lists of objects
Hi just feeling my way into Python with a small app that reads data from file, creates objects using that data, stores the objects in a list, loops over the list doing comparison tests to filter out various objects. Here is a code snippet: class myObj: def __init__(self,a,b): self.a=a self.b=b def get_a(self): return self.a def get_b(self): return self.b # Read data from file L1=[] nobj=0 for line in input: L0=line.split() a=L0[1] b=L0[2] nobj=nobj+1 an_obj=myObj(a,b) L1.append(an_obj) # Filter data for i in range(1,nobj): for x in L1:# ... loop over all objects in list a=x.get_a() # ... get value of a from current object b=x.get_b() if test(a,b): print 'test succeeded' else: print 'test failed' Trying to debug this using IDLE. The calls x.get_a and x.get_b always return zero so something is going wrong somewhere. I think I'm either not storing the objects correctly or retrieving them correctly but no idea why! All suggestions gratefully received!!! Thanks in advance Alun Griffiths ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Looping over lists of objects
Ed the problem is that my original code did not have the closing brackets for the method calls get_a and get_b whereas the code snippet I posted did. That's probably why your version works and mine failed. Thanks for your help! Alun At 17:19 24/04/2006, Ed Singleton wrote: >On 24/04/06, Etrade Griffiths <[EMAIL PROTECTED]> wrote: > > Hi > > > > just feeling my way into Python with a small app that reads data from > > file, creates objects using that data, stores the objects in a list, loops > > over the list doing comparison tests to filter out various > objects. Here is > > a code snippet: > > >[snip] > > > > Trying to debug this using IDLE. The calls x.get_a and x.get_b always > > return zero so something is going wrong somewhere. I think I'm either not > > storing the objects correctly or retrieving them correctly but no idea why! > > All suggestions gratefully received!!! > >I added some test input to give the code below, and it works fine for >me. Can you give us some test input that fails for you? Can you also >show us your test() function as it may the code in there that is >failing. > >Ed > >class myObj: > def __init__(self,a,b): > self.a=a > self.b=b > > def get_a(self): > return self.a > > def get_b(self): > return self.b > > >input = ["1 2 3", "4 5 6"] > >L1=[] >nobj=0 > >for line in input: > L0=line.split() > a=L0[1] > b=L0[2] > nobj=nobj+1 > > an_obj=myObj(a,b) > > L1.append(an_obj) > ># Filter data > >for i in range(1,nobj): > for x in L1:# ... loop over all objects in list > print "a -> ", x.get_a() # ... get value >of a from current object > print "b -> ", x.get_b() > > >It returns: > >a -> 2 >b -> 3 >a -> 5 >b -> 6 ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] unpacking PyTime
Hi
I am using the Win32com library to pick up data from an EXCEL spreadsheet
but am having trouble with dates. I want to convert a date read from the
XL sheet into a float using this snippet
from win32com.client import dispatch
import time
xlFile="test.xls"
xlApp=Dispatch("Excel.Application")
xlApp.Workbooks.Open(xlFile)
xlSht=xlApp.Worksheets("data")
# OK so far but the problem comes now ...
curr_date=xlSht.Cells(1,3).Value # returns PyTime
Not how to get the date (as either yy,mm,dd or a single number aka
XL). The ASPN ActivePython site suggests using
x=curr_date.__float__()
but Python gives the error "AttributeError: __float__"
I also tried
x=float(curr_date)
but Python gives the error "TypeError: float() argument must be string or a
number". All suggestions gratefully received!
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Re: [Tutor] unpacking PyTime
Bob
I was looking at
http://aspn.activestate.com/ASPN/docs/ActivePython/2.4/pywin32/PyTime.html
To my untrained eye it looks like there are a number of functions for
PyTime objects (eg __int__, __hash__ etc). However, I tried int(curr_date)
and it seems to work OK - thanks!
At 19:11 17/05/2006, Bob Gailer wrote:
>Etrade Griffiths wrote:
>>Hi
>>
>>I am using the Win32com library to pick up data from an EXCEL spreadsheet
>>but am having trouble with dates. I want to convert a date read from the
>>XL sheet into a float using this snippet
>>
>>from win32com.client import dispatch
>>import time
>>
>>xlFile="test.xls"
>>xlApp=Dispatch("Excel.Application")
>>xlApp.Workbooks.Open(xlFile)
>>xlSht=xlApp.Worksheets("data")
>>
>># OK so far but the problem comes now ...
>>
>>curr_date=xlSht.Cells(1,3).Value # returns PyTime
>>
>>Not how to get the date (as either yy,mm,dd or a single number aka
>>XL). The ASPN ActivePython site suggests using
>>
>It appears that the ActivePython docs may be wrong, as the only method I
>see for a PyTime object is Format. Looking up Format leads to
>curr_date.Format("%y,%m,%d") to get yy,mm,dd.
>
>Or you can, as the ActivePython docs suggest, use int(curr_date) to get an
>integer value which you can then float.
>
>--
>Bob Gailer
>510-978-4454
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[Tutor] Confused about globals
Hi
I have a series of python programs that plot stuff using PYX. Common to
these is the need to read in a list of (well) locations in (X,Y) coords so
I put that code in a separate module called shared_funcs.py. The coords
are stored in dictionaries which I want to use later in the "main" program
- every time I find a well with data, I can get the well's (x,y) coords by
looking up the well name in the dictionary. The code snippet looks like this:
=== main.py
# define coord dictionaries for global use
DE={}
DN={}
import shared_funcs()
shared_funcs.get_xy_data() # Get coords from file
... do plotting stuff
=== shared_funcs.py ===
def get_xy_data():
in_file=open("well_xy.txt","r")
for line in in_file
L=line.split()
well=L[0]
x=L[1]
y=L[2]
DE[well]=x
DN[well]=y
in_file.close()
The problem is that DE and DN appear not to be accessible to get_xy_data -
presumably this is because shared_funcs.py and main.py don't share the same
scope. So, is there any way to let get_xy_data change DE and DN? I guess
the obvious way is to pass them to get_xy_data as arguments - but is there
a more "pythonic" method? Thanks in advance!
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[Tutor] Running DOS jobs in batch
Hi
I am trying to write a PYTHON script that automates the running of an
application program MX200510.EXE under XP Pro via a DOS window. This file
is in directory
C:\Program Files\CMG\IMEX\2005.10\EXE
The command line arguments are
MX200510.EXE -f "temp.dat" -wd "C:\Projects\Vitol\New
business\Octon\simulation\full field model\0608"
My Python script is as follows:
#
# Test Python script to submit IMEX jobs
#
import os
#
# Start of MAIN program
#
# Initialisation
work_dir=r'C:\Projects\Vitol\New business\Octon\simulation\full field
model\0608'
imex_dir=r'C:\Program Files\CMG\IMEX\2005.10\EXE'
imex_fil='"temp.dat"'
imex_args=('mx200510.exe','-f',imex_fil,'-wd','"'+work_dir+'"')
nscen=2
# Check IMEX directory and files exist
os.chdir(imex_dir)
L=os.listdir(imex_dir)
for item in L:
print item
# Change directory to working directory
os.chdir(work_dir)
# Loop over N scenarios
for n in range(1,nscen):
# Spawn IMEX job and wait for completion
os.spawnv(os.P_WAIT, imex_dir, imex_args)
The output from this script is
ck9700.dll
libguide40.dll
mx200510.exe
mx200510en.chm
mx200510sp.chm
Traceback (most recent call last):
File "C:/Projects/Vitol/New business/Octon/simulation/full field
model/0608/test_imex.py", line 39, in -toplevel-
os.spawnv(os.P_WAIT, imex_dir, imex_args)
OSError: [Errno 2] No such file or directory
I tried following the ARGS into the os module using the debugger but this
did not help much, presumably because OS is precompiled. Not sure which
file or directory Python is unhappy about - LISTDIR shows that the EXE file
and path exist so presumably it's something in the way I
set up the argument list. All suggestions gratefully received!
Thanks
Alun Griffiths
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Re: [Tutor] Running DOS jobs in batch
Thanks for that Kent. I did
imex_exe=r'C:\Program Files\CMG\IMEX\2005.10\EXE\mx200510.exe'
imex_args=('mx200510.exe','-f',imex_fil,'-wd','"'+work_dir+'"')
for n in range(1,nscen):
os.spawnv(os.P_WAIT,
imex_exe, imex_args)
and it seems to work. Not sure why I need to provide the name of
the application twice though: the lib pages for spawn* say "In
either case, the arguments to the child process must start with the name
of the command being run" but hey, it works!
Thanks again
Alun
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Re: [Tutor] Traversing Excel Columns
Chris
are you looking for something like this?
xlSht=xlApp.Worksheets("Sheet1")
irow=1
XL_row_has_data=1
while XL_row_has_data:
xlRng=xlSht.Range(xlSht.Cells(irow,1),xlSht.Cells(irow,256))
ncell=xlApp.WorksheetFunction.CountA(xlRng)
if ncell ==0:
# Cells in current row are all empty
XL_row_has_data=0
else:
# Look in next row
irow=irow+1
print "first row with empty cells is row "+str(irow)
HTH
Alun Griffiths
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[Tutor] Sharing data between modules
Hi just starting to get to grips with writing GUIs in Python using wxPython and not being a computer scientist, have a philosophical question about the "best" way to pass data between various modules. For example, I anticipate having one module to look after the GUI stuff where users can input data (either from the keyboard or file), another to process the data and (probably) a third to display the calculation results. Just not sure what the most efficient way of passing data between the various modules. I can think of 4 ways to do this, of which 1 is not possible in Python (I think). (1) via temp files: modules read to and write from temporary files (2) via function arguments: data passed from one module to another via argument lists. This seems the most logical but I have an irrational dislike of long argument lists. Could pass data objects (eg. C type structs) or dictionaries via the argument list but I don't think this gets around the "problem" of long argument lists and we now need pack/unpack type functions. Maybe this isn't a problem anyway? (3) via globals: AFAIK this is not recommended so we will move swiftly on (4) indirectly: thinking here of something along the FORTRAN COMMON blocks which (I think) Python doesn't have So, looks like it's a choice between (1) and (2) - or have I missed something obvious? What is the most "pythonic" way of doing this? Thanks in advance for any suggestions ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] Getting the type of a variable
Hi I want to check the type of a variable so that I know which format to use for printing eg def print_correct_format(a): if type(a) == 'int': print "a is an integer, value %i" % (a) elif type(a) == 'float': print "a is a float, value %f" % (a) else: print "a is unknown type" The comparison type(a) == 'int' etc does not work - I'm sure there's a simple way to fix this but can't see it at the moment - any suggestions? ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Getting the type of a variable
Thanks, guys - like so many things, easy when you know how! Alun Griffiths At 14:27 27/10/2006, you wrote: Use this: if type(a) == type(1): print "a is int %d" elif type(a) == type(1.1): ... HTH.. Regards, Asrarahmed Kadri On 10/27/06, Etrade Griffiths <[EMAIL PROTECTED]> wrote: Hi I want to check the type of a variable so that I know which format to use for printing eg def print_correct_format(a): if type(a) == 'int': print "a is an integer, value %i" % (a) elif type(a) == 'float': print "a is a float, value %f" % (a) else: print "a is unknown type" The comparison type(a) == 'int' etc does not work - I'm sure there's a simple way to fix this but can't see it at the moment - any suggestions? ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor -- To HIM you shall return. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] Alternatives to PY2EXE
Hi just finished developing my first app with wxPython and matplotlib and now trying to create an EXE file using PY2EXE for distribution. However, this is proving to be an extremely frustrating experience and I am making very little progress. Are there any "simple" alternatives to PY2EXE for shipping Python apps to Windows machines? Thanks Alun Griffiths ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] Use of dateutil.relativedata
Hi trying to use dateutil to calculate the number of months between two dates. here is the script import datetime import dateutil x=datetime.date.today() y=x+datetime.timedelta(days=366) z=y-x print x,y,z a=dateutil.relativedelta(x,y) print a and here is the output >>> 2006-11-15 2007-11-16 366 days, 0:00:00 Traceback (most recent call last): File "C:/Projects/completion_dates", line 10, in -toplevel- a=dateutil.relativedelta(x,y) AttributeError: 'module' object has no attribute 'relativedelta' >>> There's problem here that's really basic but just can't see it!!! Thanks Alun Griffiths ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Use of dateutil.relativedata
Sorry, problem solved import datetime import dateutil.relativedelta x=datetime.date.today() y=x+datetime.timedelta(days=366) z=y-x print x,y,z a=dateutil.relativedelta.relativedelta(x,y) print a seems to do the trick ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Alternatives to PY2EXE
Thanks for the various advice(s) re PY2EXE alternatives. I considered installing Python on the target machines but though it would be simpler to install the EXE as I has done with C++ apps. Boy, how naive was that? Using PY2EXE is not straightforward and the documentation is fairly poor IMHO. pyInstaller sounds promising so I will check this out. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] How many loops does "break" jump out of?
Am trying to convert a C program with a GOTO in it to Python and was wondering
how many loops a Python "break" jumps out of. Here is the C pseudo code
if (test_1) {
for (;;) {
if (test_2) {
do_stuff();
} else if (test_2) {
for (ip=m1+m2+1;ip<=m;ip++) {
if (test_3) {
do_more_stuff();
if (test_4)
goto one;
}
}
for (i=m1+1;i<=m1+m2;i++)
do_even_more_stuff();
do_yet_more_stuff();
}
do_final_stuff();
one:continue_program();
Python version 1 - assumes break jumps out of outer enclosing loop
if (test_1):
while 1:
if (test_2):
do_stuff()
elif (test_2):
for ip in range(m1+m2+1, m):
if (test_3):
do_more_stuff()
if (test_4):
break
for i in range(m1+1, m1+m2):
do_even_more_stuff()
do_yet_more_stuff()
}
do_final_stuff()
continue_program()# one (break jumps out of while loop to here)
Python version 2 - assumes break jumps out of inner loop only.
if (test_1):
while 1:
if (test_2):
do_stuff()
elif (test_2):
for ip in range(m1+m2+1, m):
if (test_3):
do_more_stuff()
if (test_4):
quit_loop = true
break# jump out of for loop
if quit_loop:
break: # jump out of if test
for i in range(m1+1, m1+m2):
do_even_more_stuff()
do_yet_more_stuff()
}
# break jumps out of if loop to here
if quit_loop:
break# jump out of while loop
do_final_stuff()
continue_program()# one
Python version 3 - assumes break jumps out of for loop only.
if (test_1):
while 1:
if (test_2):
do_stuff()
elif (test_2):
for ip in range(m1+m2+1, m):
if (test_3):
do_more_stuff()
if (test_4):
quit_loop = true
break# jump out of for loop
for i in range(m1+1, m1+m2):
do_even_more_stuff()
do_yet_more_stuff()
}
# break jumps out of for loop to here
if quit_loop:
break# jump out of while loop
do_final_stuff()
continue_program()# one
Unfortunately, can't test the Python script against the C program 'cos I don't
have a C compiler. All commments gratefully received
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[Tutor] reading binary files
Hi
I am trying to read data from a file that has format
item_name num_items item_type items
eg
TIME 1 0.0
DISTANCE 10 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0
TIME 1 1.0
DISTANCE 10 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0
I can read this if the data are in ASCII format using
in_file = open("my_file.dat","r")
data1 = in_file.read()
tokens = data1.split()
and then stepping through the resulting list but the data
also appear in the same format in a binary file. I tried
converting the binary file to an ASCII file using
ifile = open("my_file.dat","rb")
ofile = open("new_file.dat","w")
base64.decode(ifile, ofile)
but that gave the error "Error: Incorrect padding". I imagine
that there is a straightforward way of doing this but haven't
found it so far. Would be grateful for any suggestions!
Thanks
Alun Griffiths
-
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Go to http://www.pipex.co.uk/business-services
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Re: [Tutor] reading binary files
Sorry, still having problems
> > I am trying to read data from a file that has format
> > item_name num_items item_type items
> >
> > eg
> >
> > TIME 1 0.0
> > DISTANCE 10 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0
>
> Where is the item_type?
Ooops, the data format should look like this:
TIME 1 F 0.0
DISTANCE 10 F 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0
F=float, D=double, L=logical, S=string etc
>
> > I can read this if the data are in ASCII format using
> >
> >in_file = open("my_file.dat","r")
> >data1 = in_file.read()
> >tokens = data1.split()
>
> It might be easier to process line by line using readline
> or readlines rather than read but otherwise, ok so far...
>
> > and then stepping through the resulting list but the data
> > also appear in the same format in a binary file.
>
> When you say a binary file do you mean an ASCII file
> encoded into binary using some standard algorithm?
> Or do you mean the data is binary so that, for example,
> the number 1 would appear as 4 bytes? If so do you
> know how strings (the name) are delimited? Also
> how many could be present - is length a single or
> multiple bytes? and are the reors fixed length or
> variable? If variable what is the field/record separator?
Sorry, no idea what the difference is. All I know is that the data
were written by a FORTRAN program using the UNFORMATTED argument
in the WRITE statement and that if they had been written FORMATTED
then we would get afile that looks something like the example above
>
> You may need to load the file into a hex editor of debugger
> to determine the answers...
>
> Having done that the struct module will allow you to read
> the data.
>
> You can see a basic example of using struct in my
> tutorial topic about handling files.
The first part of the file should contain a string (eg "TIME"),
an integer (1) and another string (eg "F") so I tried using
import struct
in_file = open(file_name+".dat","rb")
data = in_file.read()
items = struct.unpack('sds', data)
Now I get the error
error: unpack requires a string argument of length 17
which has left me completely baffled!
>
>
> --
>
> Message: 4
> Date: Mon, 02 Feb 2009 14:53:59 -0700
> From: Bernd Prager
> Subject: [Tutor] question about mpmath product expression
> To: tutor@python.org
> Message-ID:
> Content-Type: text/plain; charset="UTF-8"
>
> Does anybody know if there is a precision difference when I use mpmath and
> take an expression:
>
> from mpmath import *
> mp.dps = 100
> mu0 = [mpf('4') * pi * power(10, -7)
>
> rather then:
>
> mu0 = fprod([mpf('4'), pi, power(10, -7)])
>
> ?
>
> Thanks,
> -- Bernd
>
>
> --
>
> Message: 5
> Date: Mon, 2 Feb 2009 14:46:18 -0800 (PST)
> From: Bernard Rankin
> Subject: [Tutor] regex: not start with FOO
> To: Tutor@python.org
> Message-ID: <528538.84097...@web112218.mail.gq1.yahoo.com>
> Content-Type: text/plain; charset=us-ascii
>
> Hello,
>
>
> I'd like to match any line that does not start with FOO. (Using just a
> reg-ex rule)
>
> 1) What is the effective difference between:
>
> (?!^FOO).*
>
> ^(?!FOO).*
>
> 2) Is there a better way to do this?
>
>
> Thanks,
> :)
>
>
>
>
>
>
>
> --
>
> Message: 6
> Date: Mon, 02 Feb 2009 15:50:18 -0800
> From: "WM."
> Subject: [Tutor] newton's sqrt formula
> To: tutor@python.org
> Message-ID: <498786ba.6090...@socal.rr.com>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> # program to find square root
> square = input ('Please enter a number to be rooted, ')
> square = square * 1.0
> guess = input('Please guess at the root, ')
> guess = guess * 1.0
> newguess = 0.
>
> while guess**2 != square:
> # Newton's formula
> newguess = guess - (guess * guess - square) / (guess * 2)
> guess = newguess
> guess**2 - square
> print
> print
> print guess, ' is the square root of ', square
> print
> print
> print 'bye'
> Last month there was a square root program discussed. I wondered if the
> tide of my ignorance had receded enough that I could take a whack at
> messing with it.
> I offer this rewrite for your critique. Can it be terser, faster, prettier?
> Thank you.
>
>
>
>
> --
>
> Message: 7
> Date: Tue, 3 Feb 2009 00:44:27 -
> From: "Alan Gauld"
> Subject: Re: [Tutor] newton's sqrt formula
> To: tutor@python.org
> Message-ID:
> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
> reply-type=response
>
> "WM." wrote
>
> > square = input ('Please enter a number to be rooted, ')
> > square = square * 1.0
>
> Use raw_input() instead of input() and don't multiply
> by 1.0 - instead convert to float using float():
>
> square = float( raw_input ('Please enter a number to be rooted, '))
>
> > guess = input('Please guess at the root, ')
> > guess = guess * 1.0
> > newguess = 0.
> >
> > w
[Tutor] Reading binary files #2
Hi
following last week's discussion with Bob Gailer about reading unformatted
FORTRAN files, I have attached an
example of the file in ASCII format and the equivalent unformatted version.
Below is some code that works OK until
it gets to a data item that has no additional associated data, then seems to
have got 4 bytes ahead of itself. I
though I had trapped this but it appears not. I think the issue is asociated
with "newline" characters or the
unformatted equivalent.
Thanks in advance
Alun Griffiths
==
# Test function to write/read from unformatted files
import sys
import struct
# Read file in one go
in_file = open("test.bin","rb")
data = in_file.read()
in_file.close()
# Initialise
nrec = len(data)
stop = 0
items = []
# Read data until EOF encountered
while stop < nrec:
# extract data structure
start, stop = stop, stop + struct.calcsize('4s8si4s8s')
vals = struct.unpack('>4s8si4s8s', data[start:stop])
items.extend(vals)
print stop, vals
# define format of subsequent data
nval = int(vals[2])
if vals[3] == 'INTE':
fmt_string = '>i'
elif vals[3] == 'CHAR':
fmt_string = '>8s'
elif vals[3] == 'LOGI':
fmt_string = '>i'
elif vals[3] == 'REAL':
fmt_string = '>f'
elif vals[3] == 'DOUB':
fmt_string = '>d'
elif vals[3] == 'MESS':
fmt_string = '>%dd' % nval
else:
print "Unknown data type ... exiting"
print items
sys.exit(0)
# extract data
for i in range(0,nval):
start, stop = stop, stop + struct.calcsize(fmt_string)
vals = struct.unpack(fmt_string, data[start:stop])
items.extend(vals)
# trailing spaces
if nval > 0:
start, stop = stop, stop + struct.calcsize('4s')
vals = struct.unpack('4s', data[start:stop])
# All data read so print items
print items
-
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'IFLAGS ' 12 'INTE'
-1 2 1 10500 3 10500
2 -1 100 1 105 10500
'QFLAGS ' 10 'LOGI'
F T F F F T F F F F
'NAMES ' 3 'CHAR'
'ORTHO ' 'META' 'PARA'
'DATABEGI' 0 'MESS'
'TIME' 1 'REAL'
0.00
'DISTANCE' 10 'DOUB'
0.00D+00 1.00D+00 2.00D+00
3.00D+00 4.00D+00 5.00D+00
6.00D+00 7.00D+00 8.00D+00
9.00D+00
'CONC' 10 'REAL'
0.10495859E+02 0.10480556E+02 0.10465680E+02 0.10451221E+02
0.10437166E+02 0.10423511E+02 0.10410242E+02 0.10397354E+02
0.10384837E+02 0.10372684E+02
'DATAEND ' 0 'MESS'
test.bin
Description: Binary data
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