Things to avoid

Magic numbers, especially if they appear in more than one place. They really want to be named constants, but they also have to be named in a way that is not dependent on the actual value. For example, worldPopulation = 6,973,738,433.

The five (5) principles

... and here they are:

• Single responsibility!
• Open-closed! (but watch out for: single responsibility)
• Liskov substitution!
• Interface segregation! (see also: single responsibility)
• Dependency inversion!

No ParkHelper for you

FAIL:

../../../gcc-4.6.2/libjava/include/jvm.h:795:3: error: `ParkHelper' does not name a type

Compilers with C++11 support ...

C++11

Stdcxx wiki - C++0xCompilerSupport

C++0x/C++11 Support in GCC

Status of Experimental C++11 Support in GCC 4.7

Prerequisites for GCC

The GNU Multiple Precision Arithmetic Library (GMP)

The GNU MPFR Library (multiple-precision floating-point computations with correct rounding)

MPC (arithmetic of complex numbers with arbitrarily high precision and correct rounding)

configure: error: Building GCC requires GMP 4.2+, MPFR 2.3.1+ and MPC 0.8.0+.
Try the --with-gmp, --with-mpfr and/or --with-mpc options to specify their locations. Source code for these libraries can be found at their respective hosting sites as well as at ftp://gcc.gnu.org/pub/gcc/infrastructure/. See also http://gcc.gnu.org/install/prerequisites.html for additional info. If you obtained GMP, MPFR and/or MPC from a vendor distribution package, make sure that you have installed both the libraries and the header files. They may be located in separate packages.

GNU M4 (needed by gmp/configure: checking for suitable m4)

MPFR depends on GMP. The MPFR configure script may need help to find the GMP library and header files, e.g.

configure --with-gmp=/usr/local

(see INSTALL file).

MPC depends on MPFR and GMP. The MPC configure script can be informed about the whereabouts of gmp and mpfr, e.g.

configure --with-gmp=/usr/local --with-mpfr=/usr/local

(see INSTALL file).

The 0-1 principle, continued. The proof relies on using a monotonic mapping f which maps a pair of values a ≤ b onto a pair of values f(a) ≤ f(b). The idea is to choose f such that f(x) is either 0 or 1.

The o-1 principle: proof.

Leverage

1,168,107 (51.9%) vs 1,058,682 (47.1%) for a difference of 109,425 = 4.9% of a total of 2,249,026.

Collections
Amino acids, squared.

Full tilt

The winter solstice was just a few days ago. And, it rhymes with lattice.

A fundamental truth

It is what it is - see also: It was what it was

As a consequence, it will be what it will be.

Book

ISBN-10: 0979777747

1 = sin(x) + cos(x)

1 = C/C (C ≠ 0) =>
1 = (1/C)*(C*sin(x) + C*cos(x)) =>
1 = (1/C)*(cos(a)*sin(x) + sin(a)*cos(x)) if C = sin(a) = cos(a)
=> 1 = tan(a)
=> a = π/4 as a possible solution
=> C = 1/sqrt(2)
=> 1 = sqrt(2)*(sin(x + π/4)) or 1/sqrt(2) = sin(x + π/4)

Again, it is time for some equinox.

The answer to "what makes something/someone be ..." is looking for symptoms, not causes; the answer to "what makes something/someone do ..." is looking for causes, not symptoms. For example, the answer to "what makes someone retarded" could be "low frustration tolerance" as opposed to "hitting your head against a wall too many times". The latter could indicate an initially high frustration tolerance, which then gradually lowered. For other symptoms, such as a tendency to acquiesce to the expectations and desires of others, see Switzky/Greenspan, "What is Mental Retardation?" [Google Book].

Probability
The conditional probability P(x|y) is the probability of some event x given the occurrence of some other event y.
The marginal probability P(x) is the unconditional probability of some event x.
Bayes' theorem states that P(x|y)*P(y) = P(y|x)*P(x) = P(x ∩ y).
See the wikipedia article for details.

See also: Sklar's Theorem about copulas, as well as the wikipedia article. A copula combines the marginal, univariate distributions of a multivariate distribution into that multivariate distribution.

Crumbling Is Not An Instant's Act

Sharing

Sharing (memory) is evil the enemy of scalability.

• Reader/writer locks and their (lack of) applicability to fine-grained synchronization - Joe Duffy
• Sharing Is the Root of All Contention - Herb Sutter

CWE-609

Double-Checked Locking - a common weakness, enumerated. The complete list can be accessed here.