Istream operator
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> separators and sip any of them between each coefficient (maybe this a bitĪny clean implementation should enable normal (i.e. At least we could pre-define a list of usual > length, separators are useless, and I'd like that by default operator> skip > Since we know that we are looking for a list of numbers with predefined If ( (m1-verify).norm() > 1E-4 ) cout > verify.format(HeavyFmt) If ( (m1-verify).norm() > 1E-4 ) cout > verify.format(OctaveFmt) If ( (m1-verify).norm() > 1E-4 ) cout > verify.format(CleanFmt) If ( (m1-verify).norm() > 1E-4 ) cout > verify.format(CommaInitFmt)
![istream operator istream operator](https://cpp.openfoam.org/v8/Istream_8H__dep__incl.png)
Otherwise the 3rd inputed matrix differs from the original. If NDEBUG isn't set an assertion is spit out And, as you mentioned, inputting complex matrices is another thing we'd need to address. Of course, implementing that is still not very straight-forward, as it requires some rudimentary consistency checks (mostly that all lines are of equal length). With a tiny bit of effort, we could also accept matching pairs of parenthesis as start/end markers. End-Of-Matrix could be indicated by "\n\n" or by EOF/end-of-stream. If we don't explicitly provide formatting, we could make "\n" or " " the line separator and all other whitespace or "," the element separator. Yes, that's what I'd expect to work if we want to support istream>MatrixXd. > works out-of-the-box regardless of the actual formatting of the data. So overall, I think that we should favor flexibility to ease
Istream operator code#
> for production code for which efficient binary formats have to be used > At the end this feature is mostly useful for debugging and prototyping, not Of course, we could introduce separate classes for both (and maybe rename IOFormat to OutFormat, keeping IOFormat as alias). The name "IOFormat" kind of suggests that it defines both input and output. > could have a InFormat where we would only specify coefficient and row Moreover, IOFormat seems to be overkill for that purpose. > Aggressive checks would only be enabled when a IOFormat is explicitly (In reply to Gael Guennebaud from comment #5) Works out-of-the-box regardless of the actual formatting of the data. So overall, I think that we should favor flexibility to ease exchanging data between softwares. Auto-resizing could be enabled by default for null matrices or enabled explicitly via an option of InFormat.Īt the end this feature is mostly useful for debugging and prototyping, not for production code for which efficient binary formats have to be used anyway. Perhaps we could have a InFormat where we would only specify coefficient and row separators?Īutomatic resizing seems to be quite appealing too. At least we could pre-define a list of usual separators and sip any of them between each coefficient (maybe this a bit more tricky for complexes).Īggressive checks would only be enabled when a IOFormat is explicitly passed. Since we know that we are looking for a list of numbers with predefined length, separators are useless, and I'd like that by default operator> skip anything that is not a number.
![istream operator istream operator](https://daynhauhoc.s3.dualstack.ap-southeast-1.amazonaws.com/optimized/3X/c/8/c8bb52a157bfae31162b5d2bec928572e6f8879a_2_1035x580.png)
I agree with Chen-Pang that valid inputs are (only) those which can be > that tends to over-engineer the problem)Īnother great opportunity to defer errors caused by invalid data. > Also, should we make it possible to accept a mixture of separators? (I admit Throwing an exception (which can be caught) by invoking exceptions(ios::failbit) I'm strongly in favour of marking the stream as bad since this allows > stream as bad and provide an undefined value (or don't change the value). Standard C++ behavior would be to mark the > Another (independent) issue is what shall happen for invalid inputs. I'm strongly against the option to resize the matrix since this will > there is general agreement, that it should not (or does not have to) I can > above pull-request does not, and Helmut also seems not to require it). > We still need to decide if the input operator shall resize the matrix (the > Chen-Pang made a pull-request on this feature here: There is no limit to the number of friends a class can have.(In reply to Christoph Hertzberg from comment #3) Typically this access it given to named functions or named classes. Introduction A class can grant access to its private member variables if it wishes.