Matlab Strfind Return Index

The keyword end can be used to indicate the last row or column: A(:,end) ans = 4 8 A(:,end-1) ans = 3 7 The selected portion of the one array can be assigned to a new array: B = A(:,3:end) B = 3 4 7 8. Specify two outputs, row and col, to return the row and column subscripts of the nonzero elements. The linear index of 5 is 4 not 5! But if you want to extract row and column you just need to adapt the code Jan gave you. Which command does? My only option right now is a for loop and the strcmp command, which works, but, hey, this is Matlab!. MATLAB (matrix laboratory) is a multi-paradigm numerical computing environment and proprietary programming language developed by MathWorks. from the table of contents for a tutorial introduction to MATLAB, or use the index to find specific information. This document contains a tutorial on Matlab with a principal components analysis for a set of face images as the theme. read netcdf file using native matlab functions. Store the row and column return from find and put it in the match cell array. This MATLAB function returns the coefficients for a polynomial p(x) of degree n that is a best fit (in a least-squares sense) for the data in y. in fact, it is “orders of magnitude faster” according to her account, since it first sorts the string cell and then performs binary search. argsort(axis=1) Sort each row, return indices: Maximum and. They cover the basics of MATLAB and Simulink and introduce the most common classical and modern control design techniques. If A is a matrix, Scilab sum(A) gives the sum of all elements of A but Matlab returns the sum of each column. TF = endsWith(str,pattern) returns 1 (true) if str ends with the specified pattern, and returns 0 (false) otherwise. When eheader is numerical, converting it elementwise inside a cellfun call to a string and afterwards by char to a char matrix is cruel. For example (3 & 4) in NumPy is 0, while in Matlab both 3 and 4 are considered logical true and (3 & 4) returns 1. I would like to know how to find the indices of just the maximum (or minimum) value. In previous versions of MATLAB, you can use the “strfind” function. Ask Question. start = regexp(str,expr) returns a row vector, start, containing the indices of the substrings in str that match the regular expression string, expr. Find and match multiple values in a matrix with MATLAB's ismember function I was preparing some results of an image segmentation algorithm for publishing and needed a way to find all pixels that match a variable set of multiple numbers (e. A vector is a special case of a matrix. How to search for a string in cell array in MATLAB? Ask Question If you want to get the integer index (which you often don't need), you can use: but since the. The elements of a vector must be enclosed in square brackets. Thanks, I got it working from matt's suggestion (I left out the line) and it works fine now, I also got it working through fileparts. In general, The linear relationship is as follows:. In these tutorials, we use commands/functions from MATLAB, from the Control Systems Toolbox, as well as some functions which we wrote ourselves. The return value should be 4. Armed with this knowledge, you can compute all or some particular root. The file submission referenced in this post is no longer available on File Exchange. Made by The. I have tested the result of strfind with strcmp and == or ~= but I can't control the value. Matt's Matlab Tutorial Source Code Page. You can also use the strfind function to find matching text. But it doesn't. MATLAB Function Reference. strfind finds positions of substrings within s1 that match exactly with s2, and is case sensitive; no regular patterns. strfind issue. See the documentation for details. The idea behind these tutorials is that you can view them in one window while running MATLAB in another window. Thus, a collection of MATLAB functions can lead to a large number of relatively small files. In Matlab, the first index is 1, and this is an information you should always remember while working with for loops in Matlab. Complex Number Operations MATLAB handles complex number algebra automatically. This MATLAB function returns the coefficients for a polynomial p(x) of degree n that is a best fit (in a least-squares sense) for the data in y. ReplicationWiki was announced to the MATLAB community with this entry in the MATLAB newsgroup. MATLAB string handling. BADER and TAMARA G. In order to motivate the DSP people out there, I am showing below how one can apply a window and scale factors on a pre-framed signal using no loops and minimal memory. MATLAB is one of a few languages in which each variable is a matrix (broadly construed) and "knows" how big it is. However, "strfind" returns a cell array of indices. Save this file to your current working directory and open it in nedit. Start studying MATLAB. The first 3 elements are zero, because those elements are not greater than 3 (F), and the last are 1 because those elements are greater than 3 (T). The name must be identical to the name generated when the real-time application was built. min Returns smallest element. Output echoes the assignment performed by a statement; if the statement is not an assignment the value of the statement is assigned to the special variable ans. The strfind function also has some other options, such as the option to only return the index of the first or last match. However, “strfind” returns a cell array of indices. I script performs a task all on its own and does not return a value(s). m: This script creates a string variable containing x,y coordinates, extracts the numerical values and plots the point. length Computers number of elements. from the table of contents for a tutorial introduction to MATLAB, or use the index to find specific information. Finding Index of SIMILAR strings in txt cell (self. Python works with Modules, which you need to import if you want to use them. The abs operator returns the magnitude of its argument. Thanks, I got it working from matt's suggestion (I left out the line) and it works fine now, I also got it working through fileparts. Armed with this knowledge, you can compute all or some particular root. I want to find the position (linear or indexed) of all cells containing a string in which a certain substring of interest appe. In Matlab, the first index is 1, and this is an information you should always remember while working with for loops in Matlab. The first statement in a function is executed first, followed by the second, and so on. I also tried strfind for other things in the string, and it was fine. MATLAB allows matrix manipulations, plotting of functions and data, implementation of algorithms, creation of user interfaces, and interfacing with programs written in other languages. "newX,newY" return the final pen location. how to combine strfind and index in one line?. MATLAB always returns the first solution counter-clockwise from the positive real axis, i. MATLAB® treats the array as a single column vector with each column appended to the bottom of the previous column. MATLAB allows matrix manipulations, plotting of functions and data, implementation of algorithms, creation of user interfaces, and interfacing with programs written in other languages, including C, C++, C#, Java, Fortran and Python. So I'm tasked to make a function file that removes a dash (-) from a string, and I'm not allowed to use strrep for some reason (kinda dumb because the code works completely fine with strrep). How to search for a string in cell array in MATLAB? Ask Question If you want to get the integer index (which you often don't need), you can use: but since the. If pattern is not found in str, or if pattern is longer than str, then strfind returns the empty array, []. To find the name, access the file model_namebio. - ismember requires an exact match. Russell Cooper , Jonathan L. : idx = strfind (…, "overlaps", val) Search for pattern in the string str and return the starting index of every such occurrence in the vector idx. Define a function CalculateBMI with inputs massKg and heightCm. This is a really stupid approach, without 2 REGEXPs, CELL2MAT, DATENUM and DATESTR, which are all such powerful, that they need a lot of time. logspace Creates logarithmically spaced vector. However, "strfind" returns a cell array of indices. Implementating the use of strfind with a for loop. com wrote: > I have a cell array consisting of numbers, strings, and empty arrays. Learn more about strfind. If no occurrences are found, then findstr returns the empty array, []. Products; MATLAB Answers. m' lists all the MATLAB M-files. up vote -2 down vote favorite. See the documentation for details. A linear index allows use of a single subscript to index into an array, such as A(k). (4) Extracting elements from vectors in MATLAB. Thanks, I got it working from matt's suggestion (I left out the line) and it works fine now, I also got it working through fileparts. On UNIX, the MATLAB and LM_LICENSE_FILE variables must be set. The creator of the custom program already knows the signal name. MATLAB/Octave Description; help. To find the name, access the file model_namebio. Your Match is not a pattern in your "a" so that's why it didn't find it. If you want to return a one (true) or zero (false) then you could wrap this function within an anonymous function. If the function is to be used in several different problems or the function requires more than one MATLAB command, then you need to create a function m-file. If there is no such occurrence, or if pattern is longer than str , or if pattern itself is empty, then idx is the empty array []. findstr should only be used as internal function, in Matlab it is deprecated. "color" is the CLUT index (scalar or [r g b] triplet) that you want to poke into each pixel; default produces black with the standard CLUT for this window's pixelSize. However, “strfind” returns a cell array of indices. dirNum = currentDirectory(t) returns the index of the current image file directory (IFD). Learn more about strfind. Start studying Matlab Stuff - ENCN305. start = regexp(str,expr) returns a row vector, start, containing the indices of the substrings in str that match the regular expression string, expr. MATLAB Answers. , plotting) can also be accomplished using a command-line equivalent. returns logical 1 (true. indices = find(X, k) or indices = find(X, k, 'first') returns at most the first k indices corresponding to the nonzero entries of X. strfind 's output is not a count of how many times the string was found: the number of elements in the output corresponds to how many times the string was found. A very common programming question (e. If pattern is not found in str , or if pattern is longer than str , then strfind returns the empty array []. Matlab tutorial notes - 7 - PCA The following is a worked example with PyMS data (pyrolysis mass spectrometry) where the aim was to investigate quantitatively the levels of ampicillin mixed with either Escherichia coli or Staphylococcus aureus. string is a character array. strfind returns the index of the start of each match. Default "x" "y" is current pen location. Before finding the approximations to linear systems, it is important to remember that if A and B are both matrices, then AB is not necessarily equal to BA. Learn more about. txt) or read book online for free. I've been asked to provide a pick this week that combines. In order to get all values in a vector or array use square brackets ([]) as seen below. In previous versions of MATLAB, you can use the "strfind" function. More complicated functions. Create a variable, A, whose value is the string hello; 3. indices = find(X, k) or indices = find(X, k, 'first') returns at most the first k indices corresponding to the nonzero entries of X. ReplicationWiki was announced to the MATLAB community with this entry in the MATLAB newsgroup. Matt's Matlab Tutorial Source Code Page. -> then i try to get the right cell -> (row_index,2) the number 2 is the second column in my table. The creator of the custom program already knows the signal name. matlab: use polyfit to find slope? Lets say i have a vector x and vector y, each storing a row of 7 components. for index = values, statements, end executes a group of statements in a loop for a specified number of times. Thus, you'll either need to ad the xlswrite1. up vote -2 down vote favorite. Toggle Main Navigation. Any leading and trailing blanks in either input string are explicitly included in the comparison. cellfun can return arrays of any data type, so long as objects of that data type can be concatenated. Russell Cooper , Jonathan L. Before R2018a, to perform custom image preprocessing for training deep learning networks, you had to specify a custom read function using the readFcn property of imageDatastore. complex (Matlab function) — Returns the complex form corresponding to the given real part and imaginary part conj (Matlab function) — Complex conjugate continue (Matlab function) — Keyword to pass control to the next iteration of a loop. m in the generated code, where model_name is the name of the model. , for lack of a better nick and for the sake of www-privacy) tipped me that ismember() implements a very efficient search in string cells. Expected Range with 50% Probability = 0. If A is a matrix, Scilab sum(A) gives the sum of all elements of A but Matlab returns the sum of each column. When only one index is provided, it will index according to the structure of. MATLAB (matrix laboratory) is a multi-paradigm numerical computing environment and proprietary programming language developed by MathWorks. Getting index from strsplit or strfind in a null Learn more about strfind, strsplit, null, split string, index, search, char(0). A linear index allows use of a single subscript to index into an array, such as A(k). The for loop allows us to repeat certain commands. MATLAB - Arrays - All variables of all data types in MATLAB are multidimensional arrays. So, if A is a vector, then Scilab and Matlab work in the same way. On the course website there is a file called "simple program. Note that a scalar for the right-hand side is also acceptable and then MATLAB performs a scalar expansion to fill the left-hand side. # the return value is the index of the first zero, so we need to add 20 to get the index of 1. Sign in to comment. But it doesn't. He also holds one patent on Spaceway Beacon Assisted Control and has seven patents pending. returns the index of the end of each phase (where a pha 4년 이하 ago | 0 Implementating the use of strfind with. Learn more about it returns a list of of the first index of the start of the substring, Matlab uses Fortran. Your Match is not a pattern in your "a" so that's why it didn't find it. answer wich Matlab codes. It will only work on Windows (7 for sure but maybe not others). strfind returns the index of the start of each match. If a string array represents numbers, then you can convert it to a numeric array using the double function. will give you the indices into your string to the start of any matching elements. Run the command by entering it in the MATLAB. MATLAB Function Reference. Double click on a variable. (1) The MathWorks CheckBoxList looks nice, but as already asked here, I did not find a solution to add/remove an item. amr - strfind returns the starting index of the pattern within the string so it won't necessarily return one. It searches for the shorter string within the longer one. field if i know the value (I understand this may not be possible as it may return 2 answers but that is ok). Index: MATLAB Commands List. If no occurrences are found, then findstr returns the empty array, []. I also tried strfind for other things in the string, and it was fine. to see it in the Array Editor. I tried a lot without any results:. In this case, strfind returns 5 because the m in mary is the fifth character of str. Video created by MathWorks for the course "Exploratory Data Analysis with MATLAB". Index Entry : Section; A: abs:: Complex Arithmetic: accumarray:: Accumulation: accumarray:: Accumulation: accumdim:. Each choice is covered by a case statement. The function "sort" will allow you to order the columns or rows in the array A. I have used textread to load a data file into memory. Note: Index in Python starts from 0 not 1. One is by creating a structure or composite object with multiple variables and returning one of these populated with a value for each variable. Learn more about strfind, isempty, cellfun I want the output to give me the index of the string i want to compare. strfind issue. Matlab routines to work with space data, particularly with MMS and Cluster/CAA data. MATLAB has since been expanded and now has built-in functions for solving problems requiring data analysis, signal. However, if the same element is present more than once, index() method returns its smallest/first position. If you use any of these, you would probably want to wrap them in a function. Any leading and trailing blanks in either input string are explicitly included in the comparison. View program variables. When in this situation, the usual >> prompt changes to a K>>. function plotdat = plot_rank_histogram(fname, timeindex, varargin) %% plot_rank_histogram plots the rank histogram of the observations - segregated by level and variable. It searches for the shorter string within the longer one. To make MATLAB change this back into a 'double', type: >> double(ans) ans = 0. It was originally designed for solving linear algebra type problems using matrices. MATLAB programs are stored as plain text in files having names that end with the extension ``. Learn more about strfind. returns logical 1 (true. In general, The linear relationship is as follows:. k = strfind(str, pattern) searches the string str for occurrences of a shorter string, pattern, and returns the starting index of each such occurrence in the double array k. If fopen cannot open the file, it returns -1. Unlike the strfind function, the order of the input arguments to findstr is not important. Use strfind() to find where one string occurs as a substring in members of a string array. 1 Exercise One -40 points 1. matlab: Semicolons are used at the end of lines to suppress output. And this function will return an empty matrix if the pattern cannot be found in the string. Welcome to the Control Tutorials for MATLAB and Simulink (CTMS): They are designed to help you learn how to use MATLAB and Simulink for the analysis and design of automatic control systems. Create a variable, A, whose value is the string hello; 3. read netcdf file using native matlab functions. Matlab provides tools to assign values to a field of each array element. Find multiple strings within another string. If pattern is not found, then strfind returns an empty array, []. m to the current directory that you are running within, OR you can put the xlswrite1. , for lack of a better nick and for the sake of www-privacy) tipped me that ismember() implements a very efficient search in string cells. : idx = strfind (…, "overlaps", val) Search for pattern in the string str and return the starting index of every such occurrence in the vector idx. If m = n, eye(n) can be used. I have tested the result of strfind with strcmp and == or ~= but I can't control the value. Matlab Chapter 7 study guide by sportsnoah14 includes 17 questions covering vocabulary, terms and more. For any input cell whose text does not contain 'bla', “strfind” returns an empty cell. Output echoes the assignment performed by a statement; if the statement is not an assignment the value of the statement is assigned to the special variable ans. # the return value is the index of the first zero, so we need to add 20 to get the index of 1. In the second example, a random index in a 10 x 5 x 2 matrix of random numbers is selected with the use of three randi commands, one for each dimension. How do I print (output) in Matlab? There are three common ways: Type the name of a variable without a trailing semi-colon. MATLAB allows matrix manipulations, plotting of functions and data, implementation of algorithms, creation of user interfaces, and interfacing with programs written in other languages. If you use any of these, you would probably want to wrap them in a function. How do I see the index values of strfind ?. To make MATLAB change this back into a 'double', type: >> double(ans) ans = 0. In previous versions of MATLAB, you can use the "strfind" function. We have recently used a for loop here, while going through Euler methods in Matlab without spending a lot of time on the for loop itself, in this post we will work with the later a little intensively. The output, k, indicates the starting index of each occurrence of pattern in str. third options is the most advanced. k = findstr(str1, str2) searches the longer of the two input arguments for any occurrences of the shorter argument, returning the starting index of each such occurrence in the double array k. This is a plain text file, where the name of the file is the same as the name of the function, and the first line contains the MATLAB keyword function. In Matlab, the first index is 1, and this is an information you should always remember while working with for loops in Matlab. This MATLAB function returns the coefficients for a polynomial p(x) of degree n that is a best fit (in a least-squares sense) for the data in y. Python works with Modules, which you need to import if you want to use them. m to the current directory that you are running within, OR you can put the xlswrite1. The idea behind these tutorials is that you can view them in one window while running MATLAB in another window. Two file identifiers are automatically available and need not be opened. For example, if you sell software, you may wish to verify that the computer is licensed or activated. I tried just typing out 'F a c e r e s p o n s e' and assigning it to 'b', instead of using mystuff{977}, and strfind had no trouble locating the spaced out 'F a c e'. Use strfind() to find where one string occurs as a substring in members of a string array. Index values are one-based. returns logical 1 (true. Expected Range with 50% Probability = 0. In Matlab, everything that can be done using the GUI interface (e. how to combine strfind and index in one line?. Return an array of chart line objects from the plot function and use them to add different markers to each set of data points. Implementating the use of strfind with a for loop. matlab在命令行中运行很好,存成m文件就不行,怎么办? 谁能帮我看下 这段程序到底哪出错了 关于Matlab牛顿环仿真的程序 高手救命啊 matlab 2011a 下好了 怎么安装啊 没有setup. While the suggested answer works, it is inefficient. An evaluated switch_expression is a scalar or string. Their are 2 ways to return multiple values from a function. find Finds indices of nonzero elements. MATLAB Commands – 6 Vector, Matrix and Array Commands Array Commands cat Concatenates arrays. % KTREE = STRFIND(T,PATTERN) returns the starting indices of any % occurrences of the string PATTERN in the content of the tree T. if you want multiple returned values you need something like. startsWith and strncmp return a logical array indicating which array elements begin with the specified string, whereas validatestring returns a single string that represents the best match to the specified string. MATLAB will execute the above statement and return the following result − Name Size Bytes Class Attributes my_string 1x16 32 char Interestingly, you can use numeric conversion functions like uint8 or uint16 to convert the characters in the string to their numeric codes. Expected Range with 68% Probability = 0. % Matlab code starts here. k = strfind(str,pattern) searches the string, str, for occurrences of a shorter string, pattern, returning the starting index of each such occurrence in the double array, k. This is a really stupid approach, without 2 REGEXPs, CELL2MAT, DATENUM and DATESTR, which are all such powerful, that they need a lot of time. Toggle Main Navigation. So you get a box with nothing in it back, but you still get a box. This MATLAB function sorts the elements of A in ascending order. I imagine I can do this with strfind, but the documentation indicates it will only return the start index of the string. Best Answer: you don't put end at the "end" of a script. The strfind function also has some other options, such as the option to only return the index of the first or last match. matlab tips and tricks and page overview: I created this page as a vectorization helper but it grew to become my annotated Matlab reading cache. Use startsWith, strncmp, or validatestring, depending on your requirements, instead. But it doesn't. In these tutorials, we use commands/functions from MATLAB, from the Control Systems Toolbox, as well as some functions which we wrote ourselves. MATLAB Tensor Classes for Fast Algorithm Prototyping BRETT W. The function "sort" will allow you to order the columns or rows in the array A. Since anytime strfind reports success, the output is 1 or more positive integers, why doesn't strfind return zero (equivalent to logical false) on failure?. We have recently used a for loop here, while going through Euler methods in Matlab without spending a lot of time on the for loop itself, in this post we will work with the later a little intensively. This function is useful for selecting a random index of a vector or matrix. Create a variable, A, whose value is the string hello; 3. Learn more about strfind. Any leading and trailing blanks in either input string are explicitly included in the comparison. In contrast to variable names, literal texts are written in inverted commas: a = 'Hello'. strfind issue. TF = endsWith(str,pattern) returns 1 (true) if str ends with the specified pattern, and returns 0 (false) otherwise. At the Matlab prompt, all you need to do is type simpleprogramand it will execute the statements. A linear index allows use of a single subscript to index into an array, such as A(k). The attributes of scale factor, offset value and missing value are considered in this version. Thus, a collection of MATLAB functions can lead to a large number of relatively small files. If A is a matrix, Scilab sum(A) gives the sum of all elements of A but Matlab returns the sum of each column. For more information on MATLAB, please visit the MathWorks home. The syntax for this is as follows:. Cody is a MATLAB problem-solving game that challenges you to expand your knowledge. GitHub is home to over 40 million developers working together to host and review code, manage projects, and build software together. MATLAB allows matrix manipulations, plotting of functions and data, implementation of algorithms, creation of user interfaces, and interfacing with programs written in other languages. MATLAB stores rational numbers as doubles by default, which is a measure of the number of decimal places that are stored in each variable and thus of how accurate the values are. Learn more about strfind. He found that it solved his problem and was faster than his M-file. Find and match multiple values in a matrix with MATLAB's ismember function I was preparing some results of an image segmentation algorithm for publishing and needed a way to find all pixels that match a variable set of multiple numbers (e. How do I see the index values of strfind ?. For example, if my reference string is 'Gamma', and my cell array is {'Alpha','Beta','Gamma','Delta'}, then the result of the code should be 3. MATLAB Screen. Creating Arrays The basic data structure in Matlab is the two-dimensional array. You can convert to double with str2double: units = str2double(inputdlg(question, title)); Matlab creating mat files which names are written in the variable. Introduction to MATLAB programming Data structures Indexing cell arrays I One important concept: A n-by-m cell array is made up of n m, 1-by-1 cell arrays, I Two ways to index into and assign into a cell array:. Store the row and column return from find and put it in the match cell array. Acklam comp. Matlab: A Practical Introduction to Programming and Problem Solving Matlab: A Practical Introduction to Programming and Problem Solving By Stormy Attaway College of Engineering, Boston University Boston, MA AMSTERDAM • BOSTON • HEIDELBERG • LONDON NEW YORK • OXFORD • PARIS • SAN DIEGO SAN FRANCISCO • SINGAPORE • SYDNEY • TOKYO Butterworth-Heinemann is an imprint of Elsevier. I imagine I can do this with strfind, but the documentation indicates it will only return the start index of the string. Use the "disp" function. They are fid=1 (standard output) and fid=2 (standard error). Logical indexing will allow us to select and manipulate only those subsets of data that satisfy particular logical conditions. The syntax is a hybrid of C and Fortran and I often create polyglot statements which lead to the joyless task of squashing trivial bugs. Foundations of Finance: Index Models 2 I. MATLAB programs are stored as plain text in files having names that end with the extension ``. If none are found, find returns an empty, 0-by-1 matrix. Learn vocabulary, terms, and more with flashcards, games, and other study tools. The loop compares ii and len, finds that the statement is indeed true, so it calculates c and increments the index by one. I would like to know how to find the indices of just the maximum (or minimum) value. The idea behind these tutorials is that you can view them in one window while running MATLAB in another window. See also: find. up vote -2 down vote favorite. Learn more about strfind, isempty, cellfun I want the output to give me the index of the string i want to compare. Toggle Main Navigation. strfind finds positions of substrings within s1 that match exactly with s2, and is case sensitive; no regular patterns. We have recently used a for loop here, while going through Euler methods in Matlab without spending a lot of time on the for loop itself, in this post we will work with the later a little intensively. Specifically, this is about finding a string within another cell array of strings, where the thing I’m really interested in is the index of the cell array where the reference string occurs. Find the nonzero elements in a 4-by-2-by-3 array. I use DOS commands to query the registry in two places to identify which COM ports are connected and then check the USB section of the CurrentContrlSet to match up friendly names. MATLAB allows you to assign a different value to these constants, it is not good practice to do so. For example, '*. Without looking at his code, I asked if he had tried using strfind, despite his data not being strings. Output echoes the assignment performed by a statement; if the statement is not an assignment the value of the statement is assigned to the special variable ans. 1 Matrix and Vector Creation Commands:; Placed after a command line to suppress the output. strmatch is not recommended. MATLAB stores rational numbers as doubles by default, which is a measure of the number of decimal places that are stored in each variable and thus of how accurate the values are. We have recently used a for loop here, while going through Euler methods in Matlab without spending a lot of time on the for loop itself, in this post we will work with the later a little intensively. For any input cell whose text does not contain 'bla', “strfind” returns an empty cell. How do I print (output) in Matlab? There are three common ways: Type the name of a variable without a trailing semi-colon. MATLAB will execute the above statement and return the following result − Name Size Bytes Class Attributes my_string 1x16 32 char Interestingly, you can use numeric conversion functions like uint8 or uint16 to convert the characters in the string to their numeric codes. If the string you are searching for is not found, then empty is returned. Getting started with MATLAB As mentioned above, MATLAB has many capabilities, such as the fact that one can write programs made up of MATLAB commands. MATLAB Central contributions by arich82. Getting index from strsplit or strfind in a null Learn more about strfind, strsplit, null, split string, index, search, char(0). field]) but I want to find out the index ( I believe thats right here?) so ie how do I find x in struct(x). strfind doesn't work with arrays of strings. from the table of contents for a tutorial introduction to MATLAB, or use the index to find specific information. The file submission referenced in this post is no longer available on File Exchange. logical expression failure) occurs because strfind's behavior when no match is found is to return "[]". Armed with this knowledge, you can compute all or some particular root.