GoingNative 2012 | Channel 9
codermetrics
洋書のスペースがさらに狭くなったジュンク堂で発見。
去年の8月に出ているもの
(Codermetrics - O'Reilly Media) だったのか。
今までぜんぜんアンテナに引っかかってこなかったw
家に帰って確かめるまで、ずっと「codemetrics」と思い込んでました。
こんなサイトも → Codermetrics.org
んで、裏表紙にはこういう一文が
Codermetrics is the Moneyball for software teams. Who would have thought that
sports and software development had so much in common?
The book is purposeful and thought-provoking -- a great read for any software team participant.
容量が4GBってのだけでもいいなあ
Kindle Touch WiFi モデルが日本からも購入可能に、139ドル -- Engadget Japanese
これは自分も疑問に思ったことがあるんですが、なんでなんでしょうね。
スレ立てるまでもない質問はここで 116匹目
868 デフォルトの名無しさん [sage] 2012/02/04(土) 09:01:26.61 ID: Be:
何で日本はチャートの事をグラフって教えるんだろうか。
869 デフォルトの名無しさん [sage] 2012/02/04(土) 09:02:46.27 ID: Be:
図のことをフィギュアとは言わないなあ。
870 デフォルトの名無しさん [sage] 2012/02/04(土) 09:41:08.80 ID: Be:
マならチャートとフィギュアを使うのは当然だよな。
グラフなんて言ったら紛らわしいし。
C言語での桁落ちの以下のプログラムを教えてください | OKWave
C言語での桁落ちの以下のプログラムを教えてください
C言語の本の問題で答えが書いてなく困っております。
f(x)=xの5乗-ルート（1+xの10乗)+1/{2×ルート（1+xの１０乗）}の式が与えられ
ｘ＝0,1,2・・・50 における f(x) の値を求める場合のプログラムを教えてください。
注＊＊そのまま計算した場合と式を変形して正確に計算した場合を比較せよ（一つのプログラムで両方計算）．
何が分からないと?
補足
C言語での桁落ち：：： f(x)=xの5乗-ルート（1+xの10乗)+1/{2×ルート（1+xの１０乗）}の式
が与えられていてｘ＝0,1,2・・・50 における f(x)のプログラムです。
丸投げっぷりは脇に置いといて、R は↓こーゆーことができるので好き :)
> fx <- function(x){x**5 - sqrt(1+x**10) + 1/(2*sqrt(1+x**10))}
> fx(1:50)
[1] -6.066017e-02 -3.810975e-06 -8.711305e-09 -1.164152e-10 -4.150059e-12 -4.044512e-13 -7.689121e-13
[8] -7.105427e-15 2.710343e-12 5.583029e-12 1.370892e-11 1.197672e-12 1.113648e-11 -2.059970e-11
[15] -8.846262e-12 -2.168404e-19 1.082057e-10 1.151358e-10 -1.664620e-10 -2.121925e-10 -4.295505e-11
[22] 1.614090e-10 3.840912e-10 3.947581e-10 9.085810e-10 -7.581706e-10 -5.443981e-10 -7.500674e-10
[29] -1.700046e-09 -1.775610e-09 -1.161735e-09 -6.617445e-24 -2.125002e-09 3.554049e-09 2.069262e-09
[36] 8.185052e-10 7.210434e-09 6.310329e-09 5.541751e-09 4.882813e-09 4.315695e-09 3.825811e-09
[43] 3.401165e-09 3.031842e-09 2.709614e-09 2.427621e-09 2.180122e-09 1.962293e-09 1.770067e-09
[50] 1.600000e-09
> gx <- function(x){1/(2*sqrt(1+x**10))-sqrt(1+x**10)+x**5}
> gx(1:50)
[1] -6.066017e-02 -3.810975e-06 -8.711311e-09 -1.164153e-10 -4.092726e-12 0.000000e+00 0.000000e+00
[8] 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00
[15] 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00
[22] 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00
[29] 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00
[36] 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00
[43] 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00
[50] 0.000000e+00
> (function(x){1/(2*sqrt(1+x**10)) - sqrt(1+x**10) + x**5})(1:20)
[1] -6.066017e-02 -3.810975e-06 -8.711311e-09 -1.164153e-10 -4.092726e-12 0.000000e+00 0.000000e+00
[8] 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00
[15] 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00
式を変形して正確な値を求めるというのはこういうことですよね。
三つ目のはお遊び :)
As a software development manager I have seen productivity vary up to 10x between developers, should pay also vary up to 10x depending on productivity? : programming
が結構な伸び。
その話題の元
10x Productivity Myths: Where's the 10x Difference in Compensation? - 10x Software Development
10x Productivity Myths: Where's the 10x Difference in Compensation?
In response to my recent blog post on the research support for 10x productivity differences
among programmers, Pete McBreen made the following comment:
"One point in his article that McConnell did not address--programmer compensation
does not vary accordingly. This is a telling point--if the difference is productivity
can be 10X, why is it that salaries rarely fall outside the 2X range for experienced
developers?" [emphasis in original]
This is a good question. It's timely because the Software Engineering Productivity group
on LinkedIn has recently had a 130-comment discussion on the question of “Should pay be
tied directly to productivity?” It's also a question that I wrestled with personally for
about the first 10 years of my career. Indeed, it's part of the original reason I decided
to became self employed back in 1989 and eventually founded my own company in 1996.
The Intuitive Version of the Question
I started my personal “10x compensation quest” from the point of view of, “I know
I'm 3-5x as productive as the guy sitting next to me. Why am I not making 3-5x as much
money?” Over a period of many years I found that this formulation of the question
embodied several assumptions that were naïve or just plain wrong from a business
perspective.
Six Myths of 10x Compensation
Let's look at each of these myths of 10x compensation.
Myth 1. The guy next to me is getting paid what he's worth.
略
Published Jan 22 2011, 05:42 PM by Steve McConnell
t1: Expressing integers using four nines :: Strangely Consistent
3 Feb, 2012
by Moritz Lenz
t1: Expressing integers using four nines
(This is a guest post by Moritz Lenz. If you're wondering what this is all about, it's
the aftermath of The 2011 Perl 6 Coding Contest. If you're not wondering, it's still
about that.)
Let's consider the first task from the Perl 6 Coding Contest 2011.
Here is the description of the task once more:
What non-negative integers can you write as expressions containing exactly four occurrences
the number 9, and any of the binary operators *, /, %, +, -, prefix negations, and any
number of matching pairs of parentheses you care to use?
9 が四つと二項演算子 *, /, %, +, -、前置の negation、任意個のカッコ対を使った
式として記述できる非負の整数
#よくわからん
The program should accept an upper limit N as a command-line argument. It should then print
all integers 0..N in increasing order, along with an expression with four nines, if any
such was found.
この問題はコマンドライン引数として上限値 N を受理すべきである。
0 から N までのすべての4つの9で表現できる整数を昇順に出力する。
#でいいのかな
It was probably the easiest of all tasks, and the one we got the most submissions for. Yet
there were still some things that could go wrong, and some submissions got some of them wrong:
non-negative implies that we start at 0 = 9 + 9 - 9 - 9, not at 1
1 からではなく 0 から開始
integers means that the result must be an integer; it does not mean that intermediate
results are automatically rounded or truncated
結果は整数でなければならない。中間結果は自動的に丸められたり切りめられたりしない
the expressions must consist of four times the number 9, not the digit nine. Thus 99
is not a valid expression of two nines.
式では数字の 9 ではなく、数値の9 を4つ含んだものでなければならない。
したがって 99 は二つの9を使った vaild な式ではない
略
しかし池袋のジュンク堂、CS関連の洋書の棚をあそこまで削るとは… ○|￣|＿
紀伊國屋書店も以前よりは面積減ってるしなあ。
どうすべえ。
