셀의 표시형식을

“사용자 지정” > “[h]:mm;@”

으로 설정하면 된다.

결론부터 말하자면, 이 트램폴린은 강력 비추한다. 성인은 무슨...-_-; 초등학생이 사용해도 감당을 못 하는데...

3월에 코로나19가 심해지면서, 아이들의 외출도 줄어들면서 집에서 뛰게 해 줄 방편으로 트램폴린을 선택했다.

당시 왜 쿠팡에 꽂혔는지 모르겠는데, 암튼 와이프 계정으로 쿠팡에서 급하게 알아보고 거금 7만6천원짜리 주문을 해서 한달(?) 정도 잘 사용했다.

그런데, 얼마 지나지 않아 매트와 틀을 연결하는 고무줄이 끊어지고, 매트(?)와 연결된 고리들도 끊어지고 난리도 아니었다.

초등학교 1학년/3학년 아이들 둘이 번갈아 가면서, 2개월도 안 되었는데 더 이상 사용할 수가 없어져서, 쿠팡을 통해 서비스센터에 연락을 했다.

간단히 상황을 얘기 했는데, 흔쾌히 바로 매트와 고리를 다시 보내주겠다고 했다.

3개월도 안됐는데 이러면, 이렇게 다시 보내줘서 사용한다 해도, 얼마 안 되어서 다시 동일한 상황이 될 거 같은데 어쩌냐고 볼멘소리를 했더니, 어쩔 수 없다고, 6개월 서비스 기간이 지나면 필요한거 구입해서 사용해야 한다고.

딱 6개월짜리 제품을 7만6천원이나 받고 팔다니!!!

결국 4개월만에 사망선고를 내리고, 오늘 다 분해해서 재활용쓰레기로 배출 할 예정-_-;

서비스 기간이 9월까지 이지만, 다시 전화해서 서비스신청을 하기도 귀찮다. 신뢰가 전혀 없으니.

트램폴린이 없으면 안되는(?) 상황이라, 다른회사 제품으로 다시 주문했다. 과연 어떨 것인지.

아래 사진은 사망선고 전 날인, 어제 촬영한 사진...

어디에선가 보고 저장 했던 거라서, 저작권 문제가 있으려나...
이것도 어떤 영상을 캡쳐한게 아닌가 생각 되는데.

정말 오랜만에 블로그에 글을 작성한다.

복직하고 참 많은 일들이 있었던 대략 5개월 이었다.

휴직을 하기 전부터 하던 고민이었지만, 휴직 기간동안 생각하기로는 복직 후 모든게 잘 해결되리라 생각 했었다.

하지만 세상일이 참 마음대로 되는것이 아니고, 쉬운게 하나도 없다는 것을 새삼 깨달으며 자책하게 된다.

오늘은 아침부터 정말 답답하더라. 상당히 예민해 져서, 출근길에 아내와 약간의 언쟁이 있었다.

그리고 (다행히도) 교육을 받는 동안에는, 그나마 복잡한 일들을 잊고 교육에 집중할 수 있었다.

하지만, 퇴근시간이 되어 아이들을 데리러 가면서는 다시 답답해 지더라.

그나마 도피처가 되어 주었던 5일간의 교육이 마무리 되어 가기도 하고, 다음주 출근 할 생각을 하니 너무 답답해졌다.

아이들을 데리러 가는 길.

자꾸 우울해져서, 운전을 하면서 빠르고 유쾌한 노래를 정말 크게 틀고 달렸다.

그런데, 가슴속의 답답함이 해소되지 않아, 혼자 고함을 질러 보았다.

잠시 속이 후련해 지는가 싶더니, 이렇게 뭔가를 해소해야 하는 나 자신에 대한 연민이 느껴져서 인지, 급 더 우울해 지더라.

심지어 복받쳐 오른는 무언가에 울컥 눈물이 쏟아질 것 같았다.

억지로 참아내니, 볼 위로 눈물 한 줄기가 주르륵 흘러 내렸다.

이 우울함이 해소될 것 같지 않았지만, 아이들을 만나면서 뭔가 티가 나지 않을까 물티슈로 얼굴을 닦았다.

다행히도 아이들과의 재회장면에선 웃고 있었다.

그리고, 아이들과 이야기 하며 준비해온 젤리를 나누어 먹고, "오빠야" 노래를 함께 따라부르며 우울함이 덮였다.

(참 우연히도 "오빠야"를 언급한 지금, 폰에서 그 노래가 흘러나온다...)

정신없이 아이들을 씻기고, 과일을 먹이고 양치 후 아이들을 재웠다. 엄마는 야근 중이었고, 나는 아이들과 함께 잠이 들었다.

그러고는 새벽에 잠에서 깨어난다.

무엇이 중요한가.

내가 하고 싶은 일, 나의 경력과 무관한 일을 나의 의지와 상관 없이 하게 되었고, 그것이 너무 싫었는데...

정말 재미있게, 열정적으로 일을 하던 시절이 있다. 누구에게나 그런 기회가 주어지지는 않겠지만.

지금 누리고 있는 것들을 포기할 수 없으니, 선택의 여지가 적다. 아니 거의 없다.

그래서 더 답답하고 우울해 지고 그러는 거 같다.

지금은 빠져나갈 수 없는 개미지옥같은 곳에서 이렇게 발버둥 치고 있지만, 시간이 지나고 다시 돌아보면 어떤 생각이 들까?

그 때가 되면, 지금 이렇게 심각한 상황이 아무것도 아닌 것으로 되어 있을 수도 있다.

그래도 사람인지라, 눈 앞의 일에 미치고 환장할 것 같은걸 어쩌겠나.

혹자는 너무 조급하게 생각하지 말란다. 그러게...

나도 스스로 조급하게 생각하지 않으면 좋겠다.

뭔가 다 놓아버리면 한결 편해 질텐데 말이지.

이렇게라도 배설하고 나면 좀 나아지려나...

이러다 우울증 걸리는거 아닌가 모르겠다.

순간 순간 울컥하는 마음이 생기는데, 한숨으로 삭인다.

한방에 훅 가는게 이런게 아닌가 싶다.

나는 지금 어디로 가야 하는가.

git commit을 위해 log를 작성하다가 문득, 시제를 과거와 현재 중 어떤것으로 하는게 적절할까 의문이 들어 찾아보니, 현재 시제를 사용하는 것을 추천한다는 내용이 많더라.

내가 이 commit을 올리면서 이런이런 작업을 '했다'는 것을 기록하는 것이므로, 과거 시제가 맞다고 생각 했지만, 기준 없이 현재시제를 쓰기도, 과거 시제를 쓰기도 했다.

그런데 찾아보면서 다시 든 생각은, 보통 여럿이 작업을 하면, 다른 프로젝트의 commit을 cherry-pick이나 patch file 형태로 적용하고는 하는데, 이런 경우 가져다 쓰는 사람 입장에서는 이 commit을 적용하면 이런이런 내용이 적용'된다'고 생각하는게 맞는 것 같다. 내가 나중에 이 commit의 log를 본다면, 이게 이런이런 작업을 '하는'거구나 라고 이해 한다면, 이 또한 현재 시제가 맞는것 같고.

git이 자동으로 머지를 하거나 하면서 추가되는 자동생성 commit들도 모두 현재 시제로 log를 생성한다고 한다. (그동안 많이 봤지만, 눈여겨 보지 않아 몰랐음;;)

내 키보드를 떠나는 code/commit은 이미 내 것이 아니므로, 다른 사람의 관점에서 생각하여, 현재 시제로 작성해야겠다.ㅎㅎ

An Interview with Bjarne Stroustrup

Naturally, the editors thought he would be giving a retrospective view of seven years of object-oriented design, using the language he created.

By the end of the interview, the interviewer got more than he had bargained for and, subsequently, the editor decided to suppress its contents, 'for he good of the industry' but, as with many of these things, there was a leak.

Here is a complete transcript of what was was said,unedited, and unrehearsed, so it isn't as neat as planned interviews.

You will find it interesting...

Stroustrup: Actually, I was thinking about those days, just before you arrived. Do you remember? Everyone was writing 'C' and, the trouble was, they were pretty damn good at it. Universities got pretty good at teaching it, too. They were turning out competent - I stress the word 'competent' - graduates at a phenomenal rate. That's what caused the problem.

Interviewer: problem?

Stroustrup: Yes, problem. Remember when everyone wrote Cobol?

Interviewer: Of course, I did too

Stroustrup: Well, in the beginning, these guys were like demi-gods. Their salaries were high, and they were treated like royalty.

Interviewer: Those were the days, eh?

Stroustrup: Right. So what happened? IBM got sick of it, and invested millions in training programmers, till they were a dime a dozen.

Interviewer: That's why I got out. Salaries dropped within a year, to the point where being a journalist actually paid better.

Stroustrup: Exactly. Well, the same happened with 'C' programmers.

Interviewer: I see, but what's the point?

Stroustrup: Well, one day, when I was sitting in my office, I thought of this little scheme, which would redress the balance a little. I thought 'I wonder what would happen, if there were a language so complicated, so difficult to learn, that nobody would ever be able to swamp the market with programmers? Actually, I got some of the ideas from X10, you know, X windows. That was such a bitch of a graphics system, that it only just ran on those Sun 3/60 things. They had all the ingredients for what I wanted. A really ridiculously complex syntax, obscure functions, and pseudo-OO structure. Even now, nobody writes raw X-windows code. Motif is the only way to go if you want to retain your sanity.

Interviewer: You're kidding...?

Stroustrup: Not a bit of it. In fact, there was another problem. Unix was written in 'C', which meant that any 'C' programmer could very easily become a systems programmer. Remember what a mainframe systems programmer used to earn?

Interviewer: You bet I do, that's what I used to do.

Stroustrup: OK, so this new language had to divorce itself from Unix, by hiding all the system calls that bound the two together so nicely. This would enable guys who only knew about DOS to earn a decent living too.

Interviewer: I don't believe you said that...

Stroustrup: Well, it's been long enough, now, and I believe most people have figured out for themselves that C++ is a waste of time but, I must say, it's taken them a lot longer than I thought it would.

Interviewer: So how exactly did you do it?

Stroustrup: It was only supposed to be a joke, I never thought people would take the book seriously. Anyone with half a brain can see that object-oriented programming is counter-intuitive, illogical and inefficient.

Interviewer: What?

Stroustrup: And as for 're-useable code' - when did you ever hear of a company re-using its code?

Interviewer: Well, never, actually, but...

Stroustrup: There you are then. Mind you, a few tried, in the early days. There was this Oregon company - Mentor Graphics, I think they were called - really caught a cold trying to rewrite everything in C++ in about '90 or '91. I felt sorry for them really, but I thought people would learn from their mistakes.

Interviewer: Obviously, they didn't?

Stroustrup: Not in the slightest. Trouble is, most companies hush-up all their major blunders, and explaining a $30 million loss to the shareholders would have been difficult. Give them their due, though, they made it work in the end.

Interviewer: They did? Well, there you are then, it proves O-O works.

Stroustrup: Well, almost. The executable was so huge, it took five minutes to load, on an HP workstation, with 128MB of RAM. Then it ran like treacle. Actually, I thought this would be a major stumbling-block, and I'd get found out within a week, but nobody cared. Sun and HP were only too glad to sell enormously powerful boxes, with huge resources just to run trivial programs. You know, when we had our first C++ compiler, at AT&T, I compiled 'Hello World', and couldn't believe the size of the executable. 2.1MB

Interviewer: What? Well, compilers have come a long way, since then.

Stroustrup: They have? Try it on the latest version of g++ - you won't get much change out of half a megabyte. Also, there are several quite recent examples for you, from all over the world. British Telecom had a major disaster on their hands but, luckily, managed to scrap the whole thing and start again. They were luckier than Australian Telecom. Now I hear that Siemens is building a dinosaur, and getting more and more worried as the size of the hardware gets bigger, to accommodate the executables. Isn't multiple inheritance a joy?

Interviewer: Yes, but C++ is basically a sound language.

Stroustrup: You really believe that, don't you? Have you ever sat down and worked on a C++ project? Here's what happens: First, I've put in enough pitfalls to make sure that only the most trivial projects will work first time. Take operator overloading. At the end of the project, almost every module has it, usually, because guys feel they really should do it, as it was in their training course. The same operator then means something totally different in every module. Try pulling that lot together, when you have a hundred or so modules. And as for data hiding. God, I sometimes can't help laughing when I hear about the problems companies have making their modules talk to each other. I think the word 'synergistic' was specially invented to twist the knife in a project manager's ribs.

Interviewer: I have to say, I'm beginning to be quite appalled at all this. You say you did it to raise programmers' salaries? That's obscene.

Stroustrup: Not really. Everyone has a choice. I didn't expect the thing to get so much out of hand. Anyway, I basically succeeded. C++ is dying off now, but programmers still get high salaries - especially those poor devils who have to maintain all this crap. You do realise, it's impossible to maintain a large C++ software module if you didn't actually write it?

Interviewer: How come?

Stroustrup: You are out of touch, aren't you? Remember the typedef?

Interviewer: Yes, of course.

Stroustrup: Remember how long it took to grope through the header files only to find that 'RoofRaised' was a double precision number? Well, imagine how long it takes to find all the implicit typedefs in all the Classes in a major project.

Interviewer: So how do you reckon you've succeeded?

Stroustrup: Remember the length of the average-sized 'C' project? About 6 months. Not nearly long enough for a guy with a wife and kids to earn enough to have a decent standard of living. Take the same project, design it in C++ and what do you get? I'll tell you. One to two years. Isn't that great? All that job security, just through one mistake of judgement. And another thing. The universities haven't been teaching 'C' for such a long time, there's now a shortage of decent 'C' programmers. Especially those who know anything about Unix systems programming. How many guys would know what to do with 'malloc', when they've used 'new' all these years - and never bothered to check the return code. In fact, most C++ programmers throw away their return codes. Whatever happened to good ol' '-1'? At least you knew you had an error, without bogging the thing down in all that 'throw' 'catch' 'try' stuff.

Interviewer: But, surely, inheritance does save a lot of time?

Stroustrup: does it? Have you ever noticed the difference between a 'C' project plan, and a C++ project plan? The planning stage for a C++ project is three times as long. Precisely to make sure that everything which should be inherited is, and what shouldn't isn't. Then, they still get it wrong. Whoever heard of memory leaks in a 'C' program? Now finding them is a major industry. Most companies give up, and send the product out, knowing it leaks like a sieve, simply to avoid the expense of tracking them all down.

Interviewer: There are tools...

Stroustrup: Most of which were written in C++.

Interviewer: If we publish this, you'll probably get lynched, you do realise that?

Stroustrup: I doubt it. As I said, C++ is way past its peak now, and no company in its right mind would start a C++ project without a pilot trial. That should convince them that it's the road to disaster. If not, they deserve all they get. You know, I tried to convince Dennis Ritchie to rewrite Unix inC++.

Interviewer: Oh my God. What did he say?

Stroustrup: Well, luckily, he has a good sense of humor. I think both he and Brian figured out what I was doing, in the early days, but never let on. He said he'd help me write a C++ version of DOS, if I was interested.

Interviewer: Were you?

Stroustrup: Actually, I did write DOS in C++, I'll give you a demo when we're through. I have it running on a Sparc 20 in the computer room. Goes like a rocket on 4 CPU's, and only takes up 70 megs of disk.

Interviewer: What's it like on a PC?

Stroustrup: Now you're kidding. Haven't you ever seen Windows '95? I think of that as my biggest success. Nearly blew the game before I was ready, though.

Interviewer: You know, that idea of a Unix++ has really got me thinking. Somewhere out there, there's a guy going to try it.

Stroustrup: Not after they read this interview.

Interviewer: I'm sorry, but I don't see us being able to publish any of this.

Stroustrup: But it's the story of the century. I only want to be remembered by my fellow programmers, for what I've done for them. You know how much a C++ guy can get these days?

Interviewer: Last I heard, a really top guy is worth $70 - $80 an hour.

Stroustrup: See? And I bet he earns it. Keeping track of all the gotchas I put into C++ is no easy job. And, as I said before, every C++ programmer feels bound by some mystic promise to use every damn element of the language on every project. Actually, that really annoys me sometimes, even though it serves my original purpose. I almost like the language after all this time.

Interviewer: You mean you didn't before?

Stroustrup: Hated it. It even looks clumsy, don't you agree? But when the book royalties started to come in... well, you get the picture.

Interviewer: Just a minute. What about references? You must admit, you improved on 'C' pointers.

Stroustrup: Hmm. I've always wondered about that. Originally, I thought I had. Then, one day I was discussing this with a guy who'd written C++ from the beginning. He said he could never remember whether his variables were referenced or dereferenced, so he always used pointers. He said the little asterisk always reminded him.

Interviewer: Well, at this point, I usually say 'thank you very much' but it hardly seems adequate.

Stroustrup: Promise me you'll publish this. My conscience is getting the better of me these days.

Interviewer: I'll let you know, but I think I know what my editor will say.

Stroustrup: Who'd believe it anyway? Although, can you send me a copy of that tape?

Interviewer: I can do that.

[Note - for the humor-impaired, not a true story]

Anonymous

3월부터 개인적인 시간이 생기면서, 그동안 부족했던 부분들을 채워 보고자 Coursera.org에서 강의를 신청 했었다.

두 개의 강으로 나누어져 있는 알고리즘 강의가 있었는데, Part I은 주경야독으로 빡세게 진행 했었고, 나머지 Part II를 마져 수강 신청 했었다.

그러고는, 요즘 인공지능, 머신러닝 얘기가 하도 많아서, 상식차원에서 좀 알아야 되지 않겠나 하는 충동으로 별 생각없이 첫 강의를 본다는게 수강 신청이 되어 버렸다. ㅎㅎ

그러고는 거의 3개월 가까이, 알고리즘과 머신러닝 강의를 소화 해 내느라, 계획에 없던 정신없는 생활을 해야 했고, 결국 certi를 획득 했다. ;ㅁ;

두 강의 모두, 마지막 주차 강의를 듣는 동안에는 두 교수님들의 말씀들에 뭉클하기 까지 하더라.

어느 블로그에서, 미국에 유학을 가면, 첫 학기에는 두 과목 수강하기도 힘들다는 내용을 본 적이 있는데, 실제 학위를 받기위해 직접 수강을 하는 경우에는 온라인 수강보다 몇 배 더 어렵겠다는 생각이 들었고, 미국 유학가서 학위를 받은 사람들을 다시 바라보게 되는 계기가 되었다.

어쨌든 이 강의를 통해 알고 느끼게 된 점은

• 머신러닝이 무엇인지에 대해서 알게 되었다.
• MATLAB은 논문 쓸 때 그래프 그리는 것이 주 용도가 아니었다.
• 선형대수(Linear algebra)는 정말 중요하고 요긴하다.
• 고등학교 때 이후로 손 놓고 있었던 미분이 어렴풋이 기억 나더라.
• 3D 그래픽하면서 다시 공부했던 수학이 큰 도움이 되었다.
• 퀴즈와 과제는 문제와 지문의 이해 자체도 큰 허들이다.
• 해외(미국) 유학은 쉽지 않겠다.

기-승-전-수학이군...

끝.