In C++11 we got range-based for loops which allow one to iterate over the elements of a container easily. In some situations, however, having sequential access to each element of the container is not sufficient for the task that shall be done in the loop body. Commonly an additional counting index is required. In this… Continue reading Range-based for loops with counters
FizzBuzz is a popular test that is commonly used in job interviews for software developers. In this test one is asked to write a function that prints the numbers from 1 to 100. But for multiples of three “Fizz” has to be printed instead of the number and for the multiples of five the word… Continue reading FizzBuzz or the beauty of compile-time calculations in C++17
Floating-point exceptions During a numerical calculation various kinds of run-time errors may occur. In C++, such an error may be indicated via floating-point exceptions or via the (global but thread-local) variable errno. Floating-point exceptions are completely unrelated to C++ exceptions. When an floating-point exception is raised by an erroneous operation, the exception is simply noted… Continue reading C++11/14 for scientific computing VI
Some programming languages have functions with named parameters. Named parameters let the programmer pass the parameters to a function in any order and they are distinguished by a name. So the programmer can explicitly pass all the needed parameters and default values without worrying about the order used in the function declaration. In C++, however,… Continue reading Revisiting the named parameter idiom in C++14
In earlier posts I gave an introduction to the Message Passing Library (MPL). With MPL processes can send and receive messages with data of different data types. What kind of data types are supported by MPL? MPL supports the same kinds of elementary data types as MPI does. These are: the integer types char, short… Continue reading MPL – Data types
In a previous post I gave a very short introduction to the Message Passing Library (MPL), which is a C++ message passing library based on MPI. Although it does not provide a direct mapping of the C API to C++ it comes with all modes of collective communication as defined be the MPI standard, e.g.,… Continue reading MPL – Collective communication
The Message Passing Interface (MPI) Standard defines a message passing library, which serves as the basis for many high-performance computing applications today. It provides portable scalable functions for data exchange in parallel computations for various parallel computing architectures. Originally application programing interfaces had been defined for C and Fortran as well as for C++. In… Continue reading MPL – A message passing library
$\boldsymbol{\lambda}$ functions Anonymous functions, often called $\lambda$ functions, are a common feature of scientific programming languages, e.g., Maple and Matlab. They are particularly useful when functions are employed, which take other functions as arguments. For example, a numerical root finding algorithm requires to specify a function as an input parameter. C++11 introduces $\lambda$ functions to… Continue reading C++11/14 for scientific computing V
Random numbers C++98 inherited from C the standard functions rand and srand and the macro RAND_MAX for generating pseudo-random numbers. These functions suffer several problems. For example, it has been never specified which algorithm is used in rand to produce pseudo-random numbers. Thus, in C and in C++98 the outcome of a Monte Carlo simulation… Continue reading C++11/14 for scientific computing IV
Mathematical functions C++11/14 introduces several new mathematical functions, which are all overloaded for the types float, double and long double and that are defined in the header file cmath. The following table summerizes the new functions. Basic operations remainder signed remainder of the division operation remquo signed remainder as well as the three last bits… Continue reading C++11/14 for scientific computing III