[Numpy-discussion] eigenface image too dark
hi while trying to make an eigenface image from a numpy array of floats i tried this from numpy import array import Image imagesize=(200,200) def makeimage(inputarray,imagename): inputarray.shape=(-1,) newimg=Image.new('L', imagesize) newimg.putdata(inputarray) newimg.save(imagename) since i am using images of 200X200 size, i use an array with 4 elements like [ -92.35294118 -81.88235294 -67.58823529 ..., -3.47058824 -13.23529412 -9.76470588] the problem is ,i get an image that is too dark.it looks like a face but is too dark that even different arrays will create images that all look alike!.. s there a way to 'tone it down' so that i can generate an eigenface that can be displayed better? thanks RG ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
Re: [Numpy-discussion] eigenface image too dark
Easy solution: Use pylab's imashow(inputarray). In general ipython+matplolib are very handy for your kind of analysis Longer solution: Scale your array: a_min = inputarray.min() a_max = inputarray.max() disp_array = ((inputarray-a_min)* 255/(a_max - a_min)).astype('uint8')\ . . . newimg.putdata(disp_array) Nadav. -הודעה מקורית- מאת: [EMAIL PROTECTED] בשם royG נשלח: ד 19-מרץ-08 08:23 אל: numpy-discussion@scipy.org נושא: [Numpy-discussion] eigenface image too dark hi while trying to make an eigenface image from a numpy array of floats i tried this from numpy import array import Image imagesize=(200,200) def makeimage(inputarray,imagename): inputarray.shape=(-1,) newimg=Image.new('L', imagesize) newimg.putdata(inputarray) newimg.save(imagename) since i am using images of 200X200 size, i use an array with 4 elements like [ -92.35294118 -81.88235294 -67.58823529 ..., -3.47058824 -13.23529412 -9.76470588] the problem is ,i get an image that is too dark.it looks like a face but is too dark that even different arrays will create images that all look alike!.. s there a way to 'tone it down' so that i can generate an eigenface that can be displayed better? thanks RG ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
[Numpy-discussion] documentation for masked arrays?
Hi All, Where can I find docs for masked arrays? The paid for book doesn't even contain the phrase masked_where :-( cheers, Chris -- Simplistix - Content Management, Zope Python Consulting - http://www.simplistix.co.uk ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
[Numpy-discussion] bug with with fill_values in masked arrays?
OK, my specific problem with masked arrays is as follows: a = numpy.array([1,numpy.nan,2]) aa = numpy.ma.masked_where(numpy.isnan(a),a) aa array(data = [ 1.e+00 1.e+20 2.e+00], mask = [False True False], fill_value=1e+020) numpy.ma.set_fill_value(aa,0) aa array(data = [ 1. 0. 2.], mask = [False True False], fill_value=0) OK, so this looks like I want it to, however: [v for v in aa] [1.0, array(data = 99, mask = True, fill_value=99) , 2.0] Two questions: 1. why am I not getting my NaN's back? 2. why is the wrong fill value being used here? cheers, Chris -- Simplistix - Content Management, Zope Python Consulting - http://www.simplistix.co.uk ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
[Numpy-discussion] Can't add user defined complex types
In arrayobject.c, various complex functions (e.g., array_imag_get) use: PyArray_ISCOMPLEX - PyTypeNum_ISCOMPLEX, which is hard coded to 2 predefined types :( If PyArray_ISCOMPLEX allowed user-defined types, I'm guessing functions such as array_imag_get would just work? ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
[Numpy-discussion] Unable to file bug
http://scipy.org/scipy/numpy/newticket#preview is giving me: Internal Server Error The server encountered an internal error or misconfiguration and was unable to complete your request. Please contact the server administrator, [EMAIL PROTECTED] and inform them of the time the error occurred, and anything you might have done that may have caused the error. More information about this error may be available in the server error log. ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
Re: [Numpy-discussion] eigenface image too dark
Longer solution: Scale your array: a_min = inputarray.min() a_max = inputarray.max() disp_array = ((inputarray-a_min)* 255/(a_max - a_min)).astype('uint8')\ . thanx Nadav..the scaling works..and makes clear images but why .astype(uint8) ? can't i use the array of floats as it is ? even without changing the type as uint8 the code makes clear images when i use disp_array = ((inputarray-a_min)* 255/(a_max - a_min)) thanks again RG ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
Re: [Numpy-discussion] documentation for masked arrays?
I have found that any search on that document containing an underscore will turn up zero matches. Substitute a space instead. On Mar 19, 2008, at 5:02 AM, Chris Withers wrote: Where can I find docs for masked arrays? The paid for book doesn't even contain the phrase masked_where :-( ** Bill Spotz ** ** Sandia National Laboratories Voice: (505)845-0170 ** ** P.O. Box 5800 Fax: (505)284-0154 ** ** Albuquerque, NM 87185-0370Email: [EMAIL PROTECTED] ** ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
[Numpy-discussion] C++ class encapsulating ctypes-numpy array?
Hi, I'm passing (possibly non-contiguous) numpy arrays (data + shape + strides + ndim) with ctypes to my C++ function (with external C to make ctypes happy). Has anyone made a C++ class derived from a ctypes- numpy-array with an overloaded [] operator to allow easy indexing (e.g. x[0][2][5] for a 3D array) so that you don't have to worry about strides? I guess I'm not the first one thinking about this... Cheers, Joris Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
Re: [Numpy-discussion] C++ class encapsulating ctypes-numpy array?
Hi, On my blog, I spoke about the class we used. It is not derived from a Numpy array, it is implemented in terms of a Numpy array ( http://matt.eifelle.com/item/5) Matthieu 2008/3/19, Joris De Ridder [EMAIL PROTECTED]: Hi, I'm passing (possibly non-contiguous) numpy arrays (data + shape + strides + ndim) with ctypes to my C++ function (with external C to make ctypes happy). Has anyone made a C++ class derived from a ctypes- numpy-array with an overloaded [] operator to allow easy indexing (e.g. x[0][2][5] for a 3D array) so that you don't have to worry about strides? I guess I'm not the first one thinking about this... Cheers, Joris Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion -- French PhD student Website : http://matthieu-brucher.developpez.com/ Blogs : http://matt.eifelle.com and http://blog.developpez.com/?blog=92 LinkedIn : http://www.linkedin.com/in/matthieubrucher ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
Re: [Numpy-discussion] documentation for masked arrays?
Bill Spotz wrote: I have found that any search on that document containing an underscore will turn up zero matches. Substitute a space instead. That's not been my experience. I found the *one* mention of fill_value just fine, the coverage of masked arrays is woeful :-( Chris -- Simplistix - Content Management, Zope Python Consulting - http://www.simplistix.co.uk ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
Re: [Numpy-discussion] Help needed with numpy 10.5 release blockers
For the not blocker bugs, I think that #420 should be closed : float32 is the the C float type, isn't it ? Matthieu 2008/3/13, Jarrod Millman [EMAIL PROTECTED]: Hello, I am sure that everyone has noticed that 1.0.5 hasn't been released yet. The main issue is that when I was getting ready to tag the release I noticed that the buildbot had a few failing tests: http://buildbot.scipy.org/waterfall?show_events=false Stefan van der Walt added tickets for the failures: http://projects.scipy.org/scipy/numpy/ticket/683 http://projects.scipy.org/scipy/numpy/ticket/684 http://projects.scipy.org/scipy/numpy/ticket/686 And Chuck Harris fixed ticket #683 with in minutes (thanks!). The others are still open. Stefan and I also triaged the remaining tickets--closing several and turning others in to release blockers: http://scipy.org/scipy/numpy/query?status=newseverity=blockermilestone=1.0.5order=priority I think that it is especially important that we spend some time trying to make the 1.0.5 release rock solid. There are several important changes in the trunk so I really hope we can get these tickets resolved ASAP. I need everyone's help getting this release out. If you can help work on any of the open release blockers, please try to close them over the weekend. If you have any ideas about the tickets but aren't exactly sure how to resolve them please post a message to the list or add a comment to the ticket. I will be traveling over the weekend, so I may be off-line until Monday. Thanks, -- Jarrod Millman Computational Infrastructure for Research Labs 10 Giannini Hall, UC Berkeley phone: 510.643.4014 http://cirl.berkeley.edu/ ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion -- French PhD student Website : http://matthieu-brucher.developpez.com/ Blogs : http://matt.eifelle.com and http://blog.developpez.com/?blog=92 LinkedIn : http://www.linkedin.com/in/matthieubrucher ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
Re: [Numpy-discussion] Can't add user defined complex types
Neal Becker wrote: In arrayobject.c, various complex functions (e.g., array_imag_get) use: PyArray_ISCOMPLEX - PyTypeNum_ISCOMPLEX, which is hard coded to 2 predefined types :( If PyArray_ISCOMPLEX allowed user-defined types, I'm guessing functions such as array_imag_get would just work? I don't think that it true. There would need to be some kind of idea of complex-ness that is tested. One way this could work is if your corresponding scalar inherited from the generic complex scalar type and then that was tested for. -Travis O. ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
Re: [Numpy-discussion] Can't add user defined complex types
Travis E. Oliphant wrote: Neal Becker wrote: In arrayobject.c, various complex functions (e.g., array_imag_get) use: PyArray_ISCOMPLEX - PyTypeNum_ISCOMPLEX, which is hard coded to 2 predefined types :( If PyArray_ISCOMPLEX allowed user-defined types, I'm guessing functions such as array_imag_get would just work? I don't think that it true. There would need to be some kind of idea of complex-ness that is tested. One way this could work is if your corresponding scalar inherited from the generic complex scalar type and then that was tested for. -Travis O. You don't think which is true? Suppose along with registering a type, I can mark whether it is complex. Then we change PyArray_ISCOMPLEX to look at that mark for user-defined types. I believe get_part will just work. I more-or-less copied the code, and made my own functions 'get_real, get_imag', and they work just fine on my types. ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
Re: [Numpy-discussion] Can't add user defined complex types
On Wed, Mar 19, 2008 at 10:42 AM, Travis E. Oliphant [EMAIL PROTECTED] wrote: Neal Becker wrote: In arrayobject.c, various complex functions (e.g., array_imag_get) use: PyArray_ISCOMPLEX - PyTypeNum_ISCOMPLEX, which is hard coded to 2 predefined types :( If PyArray_ISCOMPLEX allowed user-defined types, I'm guessing functions such as array_imag_get would just work? I don't think that it true. There would need to be some kind of idea of complex-ness that is tested. One way this could work is if your corresponding scalar inherited from the generic complex scalar type and then that was tested for. That brings up a question I have. In looking to introduce float16, I noted that the typenumbers are tightly packed at the low end. There is space for user defined types =128, IIRC, but float16 and cfloat16 really belongs down with the numbers. There are also several other types in the IEEE pipeline. So I am wondering if we can't spread the type numbers out a bit more. Chuck ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
Re: [Numpy-discussion] SVD error in Numpy. NumPy Update reversed?
I recently had a personal email reply from Damian Menscher who originally found the error in 2002. He states: -- I explained the solution in a followup to my own post: http://mail.python.org/pipermail/python-list/2002-August/161395.html -- in short, find the dlasd4_ routine (for the current 1.0.4 version it's at numpy/linalg/dlapack_lite.c:21902) and change the max iteration count from 20 to 100 or higher. The basic problem was that they use an iterative method to converge on the solution, and they had a cutoff of the max number of iterations before giving up (to guard against an infinite loop or cases where an unlucky matrix would require an excessive number of iterations and therefore CPU). The fix I used was simply to increase the max iteration count (from 20 to 100 -- 50 was enough to solve my problem but I went for overkill just to be sure I wouldn't see it again). It *may* be reasonable to just leave this as an infinite loop, or to increase the count to 1000 or higher. A lot depends on your preferred failure mode: - count too low - low cpu usage, but SVD did not converge errors somewhat common - very high count - some matrices will result in high cpu usage, non-convergence still possible - infinite loop - it will always converge, but may take forever NumPy was supposedly updated also (from 20 to 100, but you may want to go higher) in bug 601052. They said the fix made it into CVS, but apparently it got lost or reverted when they did a release (the oldest release I can find is v1.0 from 2006 and has it set to 20). I just filed another bug (copy/paste of the previous one) in hopes they'll fix it for real this time: http://scipy.org/scipy/numpy/ticket/706 Damian I looked at line 21902 of dlapack_lite.c, it is, for (niter = iter; niter = 20; ++niter) { Indeed the upper limit for iterations in the linalg.svd code is set for 20. For now I will go with my method (on earlier post) of squaring the matrix and then doing svd when the original try on the original matrix throws the linalg.linalg.LinAlgError. I do not claim that this is a cure-all. But it seems to work fast and avoids the original code from thrashing around in a long iteration. I would suggest this be made explicit in the NumPy documentation and then the user be given the option to reset the limit on the number of iterations. -- Lou Pecora, my views are my own. Never miss a thing. Make Yahoo your home page. http://www.yahoo.com/r/hs ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
Re: [Numpy-discussion] SVD error in Numpy. NumPy Update reversed?
On Wed, Mar 19, 2008 at 11:30 AM, Lou Pecora [EMAIL PROTECTED] wrote: I recently had a personal email reply from Damian Menscher who originally found the error in 2002. He states: -- I explained the solution in a followup to my own post: http://mail.python.org/pipermail/python-list/2002-August/161395.html -- in short, find the dlasd4_ routine (for the current 1.0.4 version it's at numpy/linalg/dlapack_lite.c:21902) and change the max iteration count from 20 to 100 or higher. The basic problem was that they use an iterative method to converge on the solution, and they had a cutoff of the max number of iterations before giving up (to guard against an infinite loop or cases where an unlucky matrix would require an excessive number of iterations and therefore CPU). The fix I used was simply to increase the max iteration count (from 20 to 100 -- 50 was enough to solve my problem but I went for overkill just to be sure I wouldn't see it again). It *may* be reasonable to just leave this as an infinite loop, or to increase the count to 1000 or higher. A lot depends on your preferred failure mode: - count too low - low cpu usage, but SVD did not converge errors somewhat common - very high count - some matrices will result in high cpu usage, non-convergence still possible - infinite loop - it will always converge, but may take forever NumPy was supposedly updated also (from 20 to 100, but you may want to go higher) in bug 601052. They said the fix made it into CVS, but apparently it got lost or reverted when they did a release (the oldest release I can find is v1.0 from 2006 and has it set to 20). I just filed another bug (copy/paste of the previous one) in hopes they'll fix it for real this time: http://scipy.org/scipy/numpy/ticket/706 Damian I looked at line 21902 of dlapack_lite.c, it is, for (niter = iter; niter = 20; ++niter) { Indeed the upper limit for iterations in the linalg.svd code is set for 20. For now I will go with my method (on earlier post) of squaring the matrix and then doing svd when the original try on the original matrix throws the linalg.linalg.LinAlgError. I do not claim that this is a cure-all. But it seems to work fast and avoids the original code from thrashing around in a long iteration. I would suggest this be made explicit in the NumPy documentation and then the user be given the option to reset the limit on the number of iterations. Well, it certainly shouldn't be hardwired in as 20. At minimum it should be a #define, and ideally it should be passed in with the function call, but I don't know if the interface allows that. Chuck ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
[Numpy-discussion] Correlate with small arrays
Hi, I'm trying to do a PDE style calculation with numpy arrays y = a * x[:-2] + b * x[1:-1] + c * x[2:] with a,b,c constants. I realise I could use correlate for this, i.e y = numpy.correlate(x, array((a, b, c))) however the performance doesn't seem as good (I suspect correlate is optimised for both arguments being long arrays). Is the first thing I wrote probably the best? Or is there a better numpy function for this case? Regards, Peter ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
[Numpy-discussion] NumPy 1.0.5 almost ready
Hello, Thanks to everyone who has been working on getting the 1.0.5 release of NumPy out the door. Since my last email at least 12 bug tickets have been closed. There are a few remaining issues with the trunk, but we are fasting approaching a release. One additional issue that I would like to see more progress made on before tagging the next release is improved documentation especially of the new maskedarray implementation. I know that Pierre has spent a lot of time developing the new implementation and has other pressing issues, so ideally others will be able to pitch in. Given that I want to get the release out ASAP, I have decided to have a Doc Day this Friday, March 21st. I will send out an official announcement later tonight. This release promises to bring a number of important improvements and should represent a very stable and mature release in the 1.0 series of NumPy. After this release I hope to start planning for the a new major development series leading to a 1.1 release. So if you have any time to help close tickets or improve documentation, please take the time over the next few days to do so. Thanks, -- Jarrod Millman Computational Infrastructure for Research Labs 10 Giannini Hall, UC Berkeley phone: 510.643.4014 http://cirl.berkeley.edu/ ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
Re: [Numpy-discussion] Correlate with small arrays
On Wed, Mar 19, 2008 at 12:57 PM, Peter Creasey [EMAIL PROTECTED] wrote: Hi, I'm trying to do a PDE style calculation with numpy arrays y = a * x[:-2] + b * x[1:-1] + c * x[2:] with a,b,c constants. I realise I could use correlate for this, i.e y = numpy.correlate(x, array((a, b, c))) however the performance doesn't seem as good (I suspect correlate is optimised for both arguments being long arrays). Is the first thing I wrote probably the best? Or is there a better numpy function for this case? The relative performance seems to vary depending on the size, but it seems to me that correlate usually beats the manual implementation, particularly if you don't measure the array() part, too. len(x)=1000 is the only size where the manual version seems to beat correlate on my machine. -- Robert Kern I have come to believe that the whole world is an enigma, a harmless enigma that is made terrible by our own mad attempt to interpret it as though it had an underlying truth. -- Umberto Eco ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
Re: [Numpy-discussion] bug with with fill_values in maske d arrays?
OK, my specific problem with masked arrays is as follows: a = numpy.array([1,numpy.nan,2]) aa = numpy.ma.masked_where(numpy.isnan(a),a) aa array(data = [ 1.e+00 1.e+20 2.e+00], mask = [False True False], fill_value=1e+020) numpy.ma.set_fill_value(aa,0) aa array(data = [ 1. 0. 2.], mask = [False True False], fill_value=0) OK, so this looks like I want it to, however: [v for v in aa] [1.0, array(data = 99, mask = True, fill_value=99) , 2.0] Two questions: 1. why am I not getting my NaN's back? when iterating over a masked array, you get the ma.masked constant for elements that were masked (same as what you would get if you indexed the masked array at that element). If you are referring specifically to the .data portion of the array... it looks like the latest version of the numpy.ma sub-module preserves nan's in the data portion of the masked array, but the old version perhaps doesn't based on the output you are showing. 2. why is the wrong fill value being used here? the second element in the array iteration here is actually the numpy.ma.masked constant, which always has the same fill value (which I guess is 99). This is independent of the fill value for your specific array. - Matt ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
[Numpy-discussion] JOB: Short-term programming (consultant) work
Dear NumPy users, The developers of the PyDSTool dynamical systems software project have money to hire a Python programmer on a short-term, per-task basis as a technical consultant. The work can be done remotely and will be paid after the completion of project milestones. The work must be completed by July, when the current funds expire. Prospective consultants could be professionals or students and will have proven experience and interest in working with NumPy/SciPy, scientific computation in general, and interfacing Python with C and Fortran codes. Detailed work plan, schedule, and project specs are negotiable (if you are talented and experienced we would like your input). The rate of pay is commensurate with experience, and may be up to $45/hr or $1000 per project milestone (no fringe benefits), according to an agreed measure of satisfactory product performance. There is a strong possibility of longer term work depending on progress and funding availability. PyDSTool (pydstool.sourceforge.net) is a multi-platform, open-source environment offering a range of library tools and utils for research in dynamical systems modeling for scientists and engineers. As a research project, it presently contains prototype code that we would like to improve and better integrate into our long-term vision and with other emerging (open-source) software tools. Depending on interest and experience, current projects might include: * Conversion and pythonification of old Matlab code for model analysis * Improved interface for legacy C and Fortran code (numerical integrators) via some combination of SWIG, Scons, automake * Overhaul of support for symbolic processing (probably by an interface to SymPy) For more details please contact Dr. Rob Clewley (rclewley) at (@) the Department of Mathematics, Georgia State University (gsu.edu). -- Robert H. Clewley, Ph. D. Assistant Professor Department of Mathematics and Statistics Georgia State University 720 COE, 30 Pryor St Atlanta, GA 30303, USA tel: 404-413-6420 fax: 404-651-2246 http://www.mathstat.gsu.edu/~matrhc http://brainsbehavior.gsu.edu/ ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
Re: [Numpy-discussion] Numpy and OpenMP
Charles R Harris wrote: Image processing may be a special in that many cases it is almost embarrassingly parallel. Perhaps some special libraries for that sort of application could be put together and just bits of c code be run on different processors. Not that I know much about parallel processing, but that would be my first take. For me, the basic problem is that there is no support for this kind of thing in numpy right now (loading specific implementation at runtime). I think it would be a worthwhile goal for 1.1: the ability to load at runtime different implementations (for example: load multi-core blas on multi-core CPU); instead of of linking atlas/mkl, they would be used as plug-ins. This would require a significant work, though. cheers, David ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
Re: [Numpy-discussion] eigenface image too dark
I never used the putdata interface but the fromstring. It is likely that putdata is more flexible. However I urge you to use matplotlib: plotting with imshow followed by colorbar(), enables use to inspect the true pixels value, add grids, zoom etc. Nadav. -הודעה מקורית- מאת: [EMAIL PROTECTED] בשם royG נשלח: ד 19-מרץ-08 15:57 אל: numpy-discussion@scipy.org נושא: Re: [Numpy-discussion] eigenface image too dark Longer solution: Scale your array: a_min = inputarray.min() a_max = inputarray.max() disp_array = ((inputarray-a_min)* 255/(a_max - a_min)).astype('uint8')\ . thanx Nadav..the scaling works..and makes clear images but why .astype(uint8) ? can't i use the array of floats as it is ? even without changing the type as uint8 the code makes clear images when i use disp_array = ((inputarray-a_min)* 255/(a_max - a_min)) thanks again RG ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion