# ODE Solver Selection in MATLAB

Posted by Loren Shure,

Today, I'd like to welcome Josh Meyer as this week's guest blogger. Josh works on the Documentation team here at MathWorks, where he writes and maintains some of the MATLAB Mathematics documentation. In this post, Josh provides a bit of advice on how to choose which ODE solver to use. Over to you, Josh...... read more >>

# Arithmetic Associativity – Not So Fast7

Posted by Loren Shure,

Arithmetic is associative, right? Well, in the world of paper and pencil, where you can often do calculations exactly, that can be true. However, in the computing world, where real numbers can't always be represented exactly because of working with finite precision datatypes, it turns out that you can't depend on the arithmetic to behave the way you were taught in grade school.... read more >>

# Seeking Symmetry in MATLAB7

Posted by Loren Shure,

Sometimes I need to construct a matrix with certain symmetries. There are a bunch of tools in MATLAB that are well suited for such tasks. In today's post, I will mention the ones I use most often.... read more >>

# Double Integration in MATLAB – Understanding Tolerances4

Posted by Loren Shure,

In today's post, I am joined by Mike Hosea, a developer who occasionally works on integration routines for MATLAB. In recent releases, we added new integration routines, including integral2 for double integrals. Today we'll talk about some nuances in using this routine and adjusting the absolute and relative tolerances.... read more >>

# How Many Digits to Write?23

Posted by Loren Shure,

Recently, my colleague Rob Comer and I were talking about how to write out a number, in decimal, so that if it were read back into MATLAB, would retain its full precision. The question is how many digits to write out. ... read more >>

# By All Means2

Posted by Loren Shure,

Ever find yourself wanting to get some sense of some data, but not sure the arithmetic mean is what you want? You might also consider the geometric mean (geomean from Statistics Toolbox). In the image processing world, I understand that some think that images look crisper often when ... read more >>

# How to Check for Existence of Solution to Matrix Equations6

Posted by Loren Shure,

There was a great question on the newsgroup this past week asking how to determine if a system of equations had a solution. The poster wasn't (at least yet) concerned with what the solution was. ... read more >>

Posted by Loren Shure,

There continue to be a flurry of queries suggesting that MATLAB has bugs when it comes to certain operations like addition with more than values. Sometimes what prompts this is a user noticing that he or she gets different answers when using... read more >>

# Rounding Results15

Posted by Loren Shure,

There are frequent questions on the MATLAB newsgroup about rounding results to a certain number of decimal places. MATLAB itself doesn't provide this functionality explicitly, though it is easy to accomplish. ... read more >>

# Evens and Odds3

Posted by Loren Shure,

There are so many functions in MATLAB that sometimes users think that if they can't find the function they are thinking of, it's because they don't know the name. Sometimes that's true, and sometimes it's because there's a quick, easy way... read more >>