Comparison of data analysis packages R, Matlab, Sci. Py, Excel, SAS, SPSS, Stata. Lukas and I were trying to write a succinct comparison of the most popular packages that are typically used for data analysis. I think most people choose one based on what people around them use or what they learn in school, so Ive found it hard to find comparative information. Im posting the table here in hopes of useful comments. Name. Advantages. Disadvantages. Open source Typical users. RLibrary support visualization. Steep learning curve. Yes. Finance Statistics. Matlab. Elegant matrix support visualization. Expensive incomplete statistics support. No. Engineering. Sci. PyNum. PyMatplotlib. Python general purpose programming languageImmature. Yes. Engineering. Excel. Easy visual flexible. Large datasets. No. Business. SASLarge datasets. Expensive outdated programming language. No. Business Government. Stata. Easy statistical analysis. No. Science. SPSSLike Stata but more expensive and worse70. SAS, SPSS, and Stata. Theres a bunch more to be said for every cell. Among other things Two big divisions on the table The more programming oriented solutions are R, Matlab, and Python. More analytic solutions are Excel, SAS, Stata, and SPSS. Python immature matplotlib, numpy, and scipy are all separate libraries that dont always get along. Why does matplotlib come with pylab which is supposed to be a unified namespace for everything  Isnt scipy supposed to do that  Why is there duplication between numpy and scipy e. And then theres package compatibility version hell. You can use SAGE or Enthought but neither is standard yet. In terms of functionality and approach, Sci. Py is closest to Matlab, but it feels much less mature. Matlabs language is certainly weak. It sometimes doesnt seem to be much more than a scripting language wrapping the matrix libraries. Python is clearly better on most counts. Rs is surprisingly good Scheme derived, smart use of named args, etc. Everyone says SAS is very bad. Matlab is the best for developing new mathematical algorithms. Very popular in machine learning. Ive never used the Matlab Statistical Toolbox. Im wondering, how good is it compared to RHeres an interesting reddit thread on SASStata vs R. SPSS and Stata in the same category they seem to have a similar role so we threw them together. Stata is a lot cheaper than SPSS, people usually seem to like it, and it seems popular for introductory courses. I personally havent used eitherSPSS and Stata for Science weve seen biologists and social scientists use lots of Stata and SPSS. My impression is they get used by people who want the easiest way possible to do the sort of standard statistical analyses that are very orthodox in many academic disciplines. ANOVA, multiple regressions, t and chi squared significance tests, etc. Certain types of scientists, like physicists, computer scientists, and statisticians, often do weirder stuff that doesnt fit into these traditional methods. Another important thing about SAS, from my perspective at least, is that its used mostly by an older crowd. I know dozens of people under 3. SAS.   At that R meetup last week, Jim Porzak asked the audience if there were any recent grad students who had learned R in school. Many hands went up. Then he asked if SAS was even offered as an option. All hands went down. There were boatloads of SAS representatives at that conference and they sure didnt seem to be on the leading edge. But is there ANY package besides SAS that can do analysis for datasets that dont fit into memory  That is, ones that mostly have to stay on disk  And exactly how good as SASs capabilities here anyway If your dataset cant fit on a single hard drive and you need a cluster, none of the above will work. There are a few multi machine data processing frameworks that are somewhat standard e. Hadoop, MPI but Its an open question what the standard distributed data analysis framework will be. Hive Pig  Or quite possibly something else. This was an interesting point at the R meetup. Porzak was talking about how going to My. SQL gets around Rs in memory limitations. But Itamar Rosenn and Bo Cowgill Facebook and Google respectively were talking about multi machine datasets that require cluster computation that R doesnt come close to touching, at least right now. Its just a whole different ballgame with that large a dataset. SAS people complain about poor graphing capabilities. R vs. Matlab visualization support is controversial. One view Ive heard is, Rs visualizations are great for exploratory analysis, but you want something else for very high quality graphs. Matlabs interactive plots are super nice though. Matplotlib follows the Matlab model, which is fine, but is uglier than either IMO. Excel has a far, far larger user base than any of these other options. Thats important to know. I think its underrated by computer scientist sort of people. But it does massively break down at 1. Another option Fortran and CC. They are super fast and memory efficient, but tricky and error prone to code, have to spend lots of time mucking around with IO, and have zero visualization and data management support. Most of the packages listed above run Fortran numeric libraries for the heavy lifting. Another option Mathematica. I get the impression its more for theoretical math, not data analysis. Can anyone prove me wrong Another option the pre baked data mining packages. The open source ones I know of are Weka and Orange. I hear there are zillions of commercial ones too. Jerome Friedman, a big statistical learning guy, has an interesting complaint that they should focus more on traditional things like significance tests and experimental design. Here the article that inspired this rant. I think knowing where the typical users come from is very informative for what you can expect to see in the softwares capabilities and user community. Id love more information on this for all these options. What do people think Aug 2. Serbo Croatian translation. Apr 2. 01. 5 update Slovenian translation. May 2. 01. 7 update Portugese translation. FAQ MATLAB Wiki FANDOM powered by Wikia. Basics. Back to top. What is a cell array Edit. A cell is a flexible type of variable that can hold any type of variable. A cell array is simply an array of those cells. Its somewhat confusing so lets make an analogy. Installers for Microsoft Windows Octave4. The easiest way to install GNU Octave on Microsoft Windows is using MXE builds. For the current 4. Home. FreeMat is a free environment for rapid engineering and scientific prototyping and data processing. It is similar to commercial systems such as MATLAB from. In todays post, I will show you how to perform a twodimensional Fast Fourier Transform in Matlab. The 2D Fourier Transform is an indispensable tool in many fields. Issuu is a digital publishing platform that makes it simple to publish magazines, catalogs, newspapers, books, and more online. Easily share your publications and get. Tabtight professional, free when you need it, VPN service. A cell is like a bucket. You can throw anything you want into the bucket a string, an integer, a double, an array, a structure, even another cell array. Now lets say you have an array of buckets an array of cells or a Cell Array. Each bucket can contain something different, or they might all contain the same type of variable. Bucket 1 could contain a string, while bucket 2 could contain an image array of uint. Or all buckets could contain strings of various lengths. Destroy The Proxy Gate. Its totally flexible. String. ca2 my. Integer. Double. Array. ca4 rgb. Image. ca5 my. Structure. The braces should be read as contents of, so if you say ca4 rgb. Image, you are saying that the content of cell 4 is the variable rgb. XaI7hyHeCBI/VnpeeaxFVTI/AAAAAAAAAuQ/1pwuw79Jme4/s585-Ic42/ultraiso.png' alt='Matlab Full Version 64 Bit' title='Matlab Full Version 64 Bit' />Highspeed USB 2. DAQ Sustained sampling speeds up to 500kHz 12 or 16bit resolution AD converter Flexible, software configured functionality. Image. Another way to use the cell is to refer to the cell itself, rather than the contents of it, and for that you use parentheses. The item it refers to must be a cell. For example ca1 is a cell, ca2 is a cell, and ca3 is a cell, even though those cells contain variables of arbitrary, and possibly different, types. To make something a cell, you enclose it in braces, like this. String. ca2 my. Integer. Double. Array. ca4 rgb. Image. ca5 my. Structure. This set of code is entirely equivalent to the first set of code. For the first line, its basically like saying Lets get a bucket a cell and put the string into it thats what my. String by itself is. Then lets take that bucket and make it bucket 1, replacing any bucket that was already there. In other words, take the cell my. String and make it be element 1 bucket 1 of the cell array called ca. It uses parentheses which means it refers to the whole single bucket the bucket plus the contents while the first set of code used braces which refers to only the contents of the bucket. So ca1 equals the cell my. String, while ca1 equals the string my. String because the braces said to get the contents of the cell. In other words, ca1 says dont give me the bucket with the string inside, just give me the string alone, without the bucket. Its just a slight difference a slightly different way of considering it. Saying. String  or saying. String. are equivalent for the most part. You can use either way and I dont really think one way or the other is really preferred. You can use whatever way is easier for you to think about it. Maybe one way will be more intuitive for you than the other way, but again, they are equivalent. Cell arrays are similar to structures, which you probably are more familiar with, in that both are containers that can hold variables of a variety of different types arrays, strings, scalars, even other structures or cells. The difference is that with structures you refer to the different members or fields by their name e. User. Settings. my. String, while with cells you refer to them by their index number e. Here is some demo code that may help explain cell arrays, and the type of classes you get when you use braces or parentheses. Initialize a cell array with three different types of contents. First cell contains an int. Lets see whats in cell 1 and the difference between. The class of ca. 1cell is sn, classca. The class of ca. 1contents is snn, classca. Lets see whats in cell 2 and the difference between. The class of ca. 2cell is sn, classca. The class of ca. 2contents is snn, classca. Lets see whats in cell 3 and the difference between. MathWorks-MATLAB-R2016a-Direct-Link-Download.jpg' alt='Matlab Full Version 64 Bit' title='Matlab Full Version 64 Bit' />The class of ca. The class of ca. 3contents is snn, classca. Now lets see what gets displayed when we use the. Here is what celldisp returns n. One use of cell arrays is to hold lists of strings of different lengths. Since arrays are rectangular, you cant have an character array of strings unless each string was the same length or padded with blanks to be as long as the longest string. To get around that, you can use a cell array instead of a character array. Each cell in the cell array would hold a string of a different length they dont have to all be the same length like with a character array. For example. Short A little longer A really really long string. If you get strange error messages while working with cells or cell arrays, one easy thing to try is to change your braces into parentheses, or your parentheses into braces, and see if that eliminates the errors. Its also possible to mix indexing of the row and column of the cell array with the indexing of the contents of the single cell at that row and column of the cell array. For example, lets create a cell array of 2 rows and 3 columns, and in every cell of that lets put a 4 element integer array. Then well access the second element of the integer array at the cell in row 1, column 2 of the cell array. Create an empty cell array of 2 rows and 3 columns. Each element in the array is a single cell. Now, for each cell in the cell array. Number. Array randi9. Number. Array. An alternate way of specifying is given on the next line. Number. Array  Note changes in braces and parentheses. The integer array in row d, column d of the cell array d, d, d, dn. Number. Array1, random. Number. Array2, random. Number. Array3, random. Number. Array4. Print out the second element of the 4 element integer array. Ipibl-Lb Sata Driver. D array of cells. Value c1,22. The second element of the integer array in cell row d, column d is dn. Value. To visualize, imagine you had an array of buckets arranged in 2 rows and 3 columns this is our cell array, and in each bucket are 4 billiard balls arranged in a line. The above example goes to the bucket in the first row and second column, and reads off the number of the second billiard ball in that bucket. For further discussion see Loren Shures blog 1For more information, this link gives good examples about accessing cell data http www. Does MATLAB only calculate to 4 significant digits Edit. It doesnt. Dont worry your number is not truncated. It uses full double precision floating point numbers to calculate everything. Lukas and I were trying to write a succinct comparison of the most popular packages that are typically used for data analysis. I think most people choose one based on. However, by default it only prints a few decimal places to the screen in the command window. You can change this, to print out more decimal places, using the command. Why does the transpose operator take the complex conjugate Edit. When performing linear algebra operations on complex matrices, it is almost always the complex conjugate transpose also called the Hermitian transpose that is needed see Gilbert Strangs linear algebra book for discussion page 2. The bare apostrophe is an operator that takes the complex conjugate transpose. The non conjugating transpose operator is a period followed by an apostrophe. Type help punct for more info. A   complex conjugate transpose. A.   transpose. How can I detect Na. N values in a matrix or vector Edit. By definition, Na. N is not equal to any number, not even Na. N itself. Therefore there are two ways to detect Na. N values. Generate sample data. Na. N. Find Na. N values in two different ways. For speed purposes the use of isnan tends to be 2. Heres a test snippet if you want to see the comparison. A rand1. 00. 0 Random 1. ArandsizeA. Populate with Na.