Matlab Find Index Of Negative Values

05 ( p << 0. If you have a non-unity feedback situation, look at the help file for the MATLAB function feedback, which demonstrates how to find the closed-loop transfer function with a gain in the feedback path. Privacy & Cookies: This site uses cookies. Here, I want the index 4 1, in some form, back. min(A(:)) A. Find indices and values of nonzero elements. MATLAB: Workshop 3 - Vectors in MATLAB page 3 • Working with vectors in MATLAB MATLAB has two types of vectors (row and column) and offers several methods for creating vectors for use. This is known as short format. Wilson, Bruce Miller, Maria Luisa Gorno Tempini, and Shrikanth S. I am interested in finding the indices of the first (by index) negative number in the bottom row of any matrix T. however, if you use: hist(a,b), then the repetitions are counted against the reference (b). For example a function that compute pi should never use fprintf. BMP Version 2 (Microsoft Windows 2. 001): there was a tendency for participants (now senders) to maintain their code and for receivers to adjust more frequently their mappings during coordination than senders did. % Functions are also m-files. Remember that. , creating x-y plots, that do not fall under the rubric of linear algebra. How to remove negative numbers in an array in Matlab? lets say a function X outputs an array X = [5 7 2 -3 2 -8 -1]. We want not just to store values but also to be able to quickly access each individual value. Wilson, Bruce Miller, Maria Luisa Gorno Tempini, and Shrikanth S. In one example the best we will be able to do is estimate the eigenvalues as that is something that will happen on a fairly regular basis with these kinds of problems. These investments probably won’t make you rich right away, but over the long-term they offer the potential for steady, positive returns. My guess is that you want to iterate in that cell, and probably what people is suggeting you ( create a normal array) is the best way to approach. Based on porous silicon (PSi) microarray images, we propose a new method called the phagocytosis algorithm (PGY) for removing the influence of speckle noise on image gray values. The indices are counted from zero, not one. July's reading was 124. For example, the command [row,col,v] = find(X>1) returns a column vector of logical 1 (true) values for v. MATLAB Functions MATLAB Functions are similar to functions in Fortran or C. Index 44 1 Introduction 1. We will use a naming convention that vector variable names contain only lower case letters. Finding out how to normalize data in Excel is an invaluable skill in situations such as this. For exam-ple, you might prefer to use the variable xin a number of different calculations. If we test in a high prevalence setting, it is more likely that persons who test positive truly have disease than if the test is performed in a population with low prevalence. The Rand index gives equal weight to false positives and false negatives. In such a case, you should interpret the value of Kappa to imply that there is no effective agreement between the two rates. MATLAB Answers. Example: Sam does an experiment to find how long it takes an apple to drop 2 meters. Given a row vector: a) I need to select all the positive numbers and then make them zero. example: looking. This requires that a peak detector be "tuned" or optimized for the desired peaks. Windows users should not attempt to download these files. For more information on those topics see one of our tutorials on vectors ( Introduction to Vectors in Matlab ), matrices ( Introduction to Matrices in Matlab ), vector operations ( Vector. Open Mobile Search Finding maximum value and it's location from the matrix. x = x+1 This means "get the current value of x, add one, and then update x with the new value. CSAVE ""[, ] Command Saves a program to cassette. Expert method: type the following code. Finding the index value corresponding to a value Learn more about find MATLAB. The first step is to set up vectors that represent the range of x and y values. all True if all elements of a vector are nonzero. We will use a naming convention that vector variable names contain only lower case letters. Wilson, Bruce Miller, Maria Luisa Gorno Tempini, and Shrikanth S. An array stores a sequence of values that are all of the same type. So the output would be a 1xn vector, where the i-th element is the maximum number of consecutive negative values for column "i". This is NOT something that the user can vary. matlabs max function only does 1 dimension. At fair value, there is no positive nor negative bias that the two markets mutually exert on each other. When all negative cash flows occur earlier in the sequence than all positive cash flows, or when a project's sequence of cash flows contains only one negative cash flow, IRR returns a unique value. For this reason, even if you find out in some future Matlab release that TextPrims, EdgePrims and FacePrims don’t exist, perhaps they still exist and simply have different names. m basic equivalent to MATLAB's HISTC function for weighted data. 4 Christina Hagedorn, Michael I. Finding out how to normalize data in Excel is an invaluable skill in situations such as this. Example: [1 2 5 7 5 7 4 3] Returns 7 and 4. Our aim is to find some local maxima and minima on the graph, so let us find the local maxima and minima for the interval [-2, 2] on the graph. int a[5]; and initially in the state:. But in the case of negative values, do I take lowest value (in this case -801) or the lowest number among negative & positive values (67)?? Hoping for your reply. Trade tensions, coupled with falling growth and inflation. A % Matlab's command line is a little like a standard shell: % - Use the up arrow to recall commands. We want not just to store values but also to be able to quickly access each individual value. way to get the index of a row in which two (or n) values exist. Negative Log Calculator. The spreadsheet pictured above, PeakAndValleyDetectionTemplate. MATLAB Answers. Similarly, when a negative value becomes more negative than the most negative representable number, the result is negative. Note that in Scilab, second input parameter can give the dimension to use to find the maximum values or another matrix (maximum of two matrices), in Matlab, dimension parameter is given in a third input parameter (in. 81787768047 4 4868. Notes: When n = 2 an nth root is called a square root. (MatLab chooses the values such that the sum of the squares of the elements of each eigenvector equals unity). COMSOL is the developer of COMSOL Multiphysics software, an interactive environment for modeling and simulating scientific and engineering problems. A correlation coefficient value of zero would indicate that the data are randomly scattered and have no pattern or correlation in. Inside those areas both positive and negative high correlations exist at pressure levels ranging from 850 to 700 hPa, with the peak values near 775 hPa. Chapter 5 Iteration 5. 5 has a total of 200 x 0. Use the Matlab find function to find the index of the first three entries in the array x. [code]help max [/code] Scan through the help file for how to get the index! Beginner method: [code]vec = [1 2 7 4 3 5 8 19 47 35 6 -7] [value index] = max(vec)[/code] If I remember Matlab. To calculate percentiles, sort the data so that x1 is the smallest value, and xn is the largest,. The MatLab DSP Toolbox makes this super easy with its findpeaks function. Times and dates in your local timezone. For example, you can count the number of characters that are contained in a range of cells, sum only numbers that meet certain conditions (such as the lowest values in a range or numbers that fall between an upper and lower boundary), and sum. Variables in a script file are global and will change the % value of variables of the same name in the environment of the current % Matlab session. For more information on those topics see one of our tutorials on vectors ( Introduction to Vectors in Matlab ), matrices ( Introduction to Matrices in Matlab ), vector operations ( Vector. The frequent development of a nocturnal drainage flow with wind velocities of over 10 m s-1, the typical lake breeze during the day, its onset and vertical. The overshoot is a result of the zero added in the lag controller. Indexing into a matrix with a single subscript in this way is often called linear indexing. How to locate the first negative number?. The negative outlook signals in part Moody's rising concern that the government will not find the political capital to implement the range of measures it intends, and that its plans will be largely ineffective in lifting growth. ? Then computes and prints out the sum of the first k integers. Open Mobile Search. Find index of cells containing my string. Then k is simply k = col + row*n. Place Value of a Number This selection will help you to find what the place value is of a particular digit in a number. ^2)) Let's go go trough the used functions step-by-step, with the example vec. The closer the value is to , the better the linear fit. The default value of k is zero, so that triu and tril normally include the main diagonal as part of the result matrix. if you use: hist(a), matlab will divide the whole range of values to 10 periods, and count the repetitions of values lying within these ranges. How to find Negative of Image in Matlab A negative is an image in which the lightest areas of the photographed subject appear darkest and the darkest areas appear lightest. For example, if A is an array of type double, then ismissing(A,[0,-99]) treats 0 and -99 as missing double values instead of NaN. any True if any element of a vector is nonzero. normalization Published on July 10, 2007 June 2, 2014 in data preprocessing , normalization , scaling , standardization by Sandro Saitta In the overall knowledge discovery process, before data mining itself, data preprocessing plays a crucial role. Simulink will recognize these MATLAB variables for use in the model. The 'find' command only returns the indices of all the non-zero elements of a matrix. Calculating a Geometric Mean with some negative values I am trying to work out how to calculate the geometric mean of a series of values, some of which are negative, ie. The nonzeros can be explicitly listed using ( [row_index, column_index, value] = find(A) ). Is there any easy way to check for a negative value in an array in matlab? Matlab Find Value In Array. We can neither trust science and scientists explicitly, nor should we dismiss all of science as hopelessly biased and flawed. My solution is fairly short, and demonstrates some of my favorite MATLAB techniques. A vector is a matrix with only one row or only one column. What happens when an integer is divided by zero. 1 Updating variables A common pattern in assignment statements is an assignment statement that updates a variable - where the new value of the variable depends on the old. Narayanan, Angela Nazarian, and David Traum. How to find vector elements between two values, efficiently how to find its position from matrix,index of that. Flow-of-control. Show Hide all comments. Main: We use Array. A curated list of awesome Matlab frameworks, libraries and software. MATLAB likes to do this and will tell you what it has produced after an assignment statement unless you request otherwise. Im plotting a graph of X against Y and i want to know the value of X when Y = 0. Finding the index of the a field of a structure? I want to find the max of a field in a structure so i use max([struct. As long as x1 and x2 are both non-negative the expression itself will be non-negative since neither s1 nor s2 can ever be negative. According to the FPP method and FANP, all the local weights have a lower bound of zero, and the lower bound of consistency index is negative infinity. An array formula (one that spans multiple cells) can do calculations on rows and columns of cells where you might otherwise need to use several formulas. If you want to use logarithm of [code ]x[/code] to the base 10, you need to use log10(x). I think it would have been better if you did an example where you actually reduced the dimensionality by selecting a subset of feature vectors. Data Types, Arrays and Strings. The value of fid is only set when output is sent to a le. Learn more about vector, indexing, equals MATLAB. But first, some quick definitions… The Jaccard index is the same thing as the Jaccard similarity coefficient. We can use the F measure measuresperf to penalize false negatives more strongly than false positives by selecting a value , thus giving more weight to recall. - For instance our array/list is of size n, then for positive index 0 is the first index, 1 second, last index will be n-1. Interested readers can find out more information about integrating Java controls in Matlab GUI in my book "Undocumented Secrets of MATLAB-Java Programming" (CRC Press, 2011, ISBN 978-1439869031). prod Product of elements. an imaginary number. % Functions are also m-files. This reversed order occurs because the extremely light-sensitive chemicals a camera film must use to capture an image quickly enough for ordinary picture-taking are darkened. Today's Topics • Using MATLAB as a calculator. COMSOL is the developer of COMSOL Multiphysics software, an interactive environment for modeling and simulating scientific and engineering problems. Matlab will automatically figure out how many entries you need and their values. It is nice to see the MatLab code on your blog. Often an IndexOutOfRangeException can provoked by using the -1 in other code (like an array access). CSGN () Function Converts the value of to a single precision real value, and returns its result. Calculating a Geometric Mean with some negative values I am trying to work out how to calculate the geometric mean of a series of values, some of which are negative, ie. If a vector has n elements and a new value is assigned to an element with an address of n + 2 or larger, MATLAB assigns zeros to the elements that are between the last original element and the new. I have an array of size 401 x 381 which has positive and negative values. [code]help max [/code] Scan through the help file for how to get the index! Beginner method: [code]vec = [1 2 7 4 3 5 8 19 47 35 6 -7] [value index] = max(vec)[/code] If I remember Matlab. The task of creating a vector of equally (or linearly) spaced points between two limits occurs so commonly that MATLAB has a special command linspace to do this. As far as I aware there is no function doing this for you. ^2)) Let's go go trough the used functions step-by-step, with the example vec. 95, and a unit negative charge at location x = 1. More elegant approaches would reassign the value to -1/eps or –Inf. Using the colon operator : and other methods for accessing information in a matrix. But in the case of negative values, do I take lowest value (in this case -801) or the lowest number among negative & positive values (67)?? Hoping for your reply. MATLAB is used mostly for technical and scientific computing and is an alternative to more traditional languages, such as C or FORTRAN, when the speed of the final code isn't an issue. , creating x-y plots, that do not fall under the rubric of linear algebra. The absolute value of k must not be greater than the number of sub- or super-diagonals. A script with name "script1. 3: valArray. Physics Forums | Science Articles, Homework Help, Discussion. How to Find Position of First Negative Value in List? How can I set up a formula to find the position of the first negative (or text) value in a list? I have a list of values (let's say in cells A1:A20) that can be positive, zero, negative, or the text "END" (indicating the end of the list if there are fewer than 20 values). the output is sent. Here are the rules for that int value: Return a negative value if this object is smaller than the other object. i have to find the index of the same value in an array,see the following example. My guess is that you want to iterate in that cell, and probably what people is suggeting you ( create a normal array) is the best way to approach. In simulation, however, t is not necessarily the simulation clock time. They meant indices of each column of A as if each column were it's own column vector, while you were hoping that indices mean "linear indices" which is often used elsewhere. For example, to return output values in a cell array, specify 'UniformOutput',false. Symbolic Math in Matlab. Many other commands similar to max give both the values and the indices correctly. Each MATLAB figure window has a colormap associated with it. We can use the F measure measuresperf to penalize false negatives more strongly than false positives by selecting a value , thus giving more weight to recall. For example, on the first iteration, index = valArray(:,1). Interested readers can find out more information about integrating Java controls in Matlab GUI in my book "Undocumented Secrets of MATLAB-Java Programming" (CRC Press, 2011, ISBN 978-1439869031). MATLAB is a high-level programming language that does not require managing memory details. MATLAB provides ample tools for performing mathematical operations. To find text or numbers, press Ctrl+F, or go to Home > Editing > Find & Select > Find. 4 Christina Hagedorn, Michael I. On 2003-02-18 17:34, Kypros wrote: I need a formula which will detect the first instance of a number which is less than 0 in a column of numbers and return that number and a number from the cell 4 cells to the left of it, and place those numbers in two cells. Sign in to comment. Ideas that work would be greatly appreciated!. Inside those areas both positive and negative high correlations exist at pressure levels ranging from 850 to 700 hPa, with the peak values near 775 hPa. If the energy value is greater than the threshold value a counter is incremented. Which way normalizing data is better using matlab inbuilt function 'normc(vector)' or normalizing to range 0 to 1 by using 'mat2gray'? when I apply these functions output of both are completely different. For frequent access to the same chart, right-click and save the file to your disk. Sir, how can i get the mean and standard deviation and total numbers of negative values and similarly for positive values in a matrix A(i,j). Read from a text file >> fid = fopen(‘filename. MATLAB will execute the above statement and return the following result − final_velocity = 196 The format Command. indices = find(X, k) or indices = find(X, k, 'first') returns at most the first k indices corresponding to the nonzero entries of X. Other supported data objects. Example of the Power method with Matlab. How to find the two nearest values related to a Learn more about vector, nearest, closest MATLAB. We examined their finger prick blood samples for malaria parasitaemia using CareStartTM histidine rich protein II (HRP-2) RDT and microscopy. The real power of Matlab is the ease in which you can manipulate your vectors and matrices. MATLAB Central. Obviously, only vectors that have the same number of elements can be added or subtracted. So the output would be a 1xn vector, where the i-th element is the maximum number of consecutive negative values for column "i". If this approximated value of pi is of interest to the user, then the main program can print the result. Color mapping is a visualization technique in which each scalar value in the data set is mapped through a lookup table to a specific color. A correlation coefficient value of zero would indicate that the data are randomly scattered and have no pattern or correlation in. 5 has a total of 200 x 0. Tiffany is trading much closer to its intrinsic value than LVMH or Hermès (although I still see Tiffany as slightly overvalued) and with a dividend yield of 2. For example, on the first iteration, index = valArray(:,1). Published with MATLAB® 9. But: If nothing is found, Array. Remember that. RE: Is there a MATLAB function that can find the index of a specified double in a vector? For example: vector= [ 10, 20, 30, 40, 50 ]. Table 1: Summary of format codes for use with fprintf and fscanf. index = 1 for n = -123. Such systems evolve over multiple stages, with the dynamics in each stage depending on both the current state of the system and the state at delayed times. Here are the elements of the matrix A along with their linear indices. A couple of days ago, a reader of this blog posted a comment, asking whether it is possible to change Matlab’s Desktop color scheme, and its general UI look. Finding out how to normalize data in Excel is an invaluable skill in situations such as this. Note that +1 indicates a perfect fit (the paired values lie on a straight line) with a positive slope, while -1 indicates a perfect fit with a negative slope. In multiple regression, the variance inflation factor (VIF) is used as an indicator of multicollinearity. using individual price points. This procedure will let you call any of the matlab toolbox functions from anywhere. A script with name "script1. We examined their finger prick blood samples for malaria parasitaemia using CareStartTM histidine rich protein II (HRP-2) RDT and microscopy. That is the the higher value of D(i,i) the more important the corresponding eigenvector. Find Minimum Matlab. The list is not sorted alphabetically. TOPOSURF Visualisation of topological Surfaces/Images ***** Intro for Syntax The Configuration of TOPOSURF has various Parameters to Control the Layout, Colors, Data to show, etc. MATLAB will execute the above statement and return the following result − final_velocity = 196 The format Command. raise 10 to any power, positive or negative the result is always positive Log is the inverse of this, trying to find the log of a negative number is exactly like trying to find an index that when 10 is raised to it you get a negative answer. Since MATLAB is an interpret language, every line will be complied when it is exe-cuted. I need to find the largest negative number in an array that also contains positive numbers. However, if you want more precision, you need to use the format command. A Quick Introduction to Loops in Matlab The increment can be any positive or negative number sum. Pearson correlation is selected, and the output return r and p-value. It does not address the quadrants where x is. Learn more about vector, indexing, equals MATLAB. MATLAB MATLAB is a software package for doing numerical computation. Forum adverts like this one are shown to any user who is not logged in. find all elements in the array a that has value 1 or 2). Does this mean that the magnitude of a vector can be negative too? Also, I'm wondering if there's a difference between the absolute value and magnitude of a vector like -3i-4j. The lab sessions are used with one main goal: to allow students to become familiar with computer software (e. Please see matlab/README for details. Making 3D surface plots, contour plots, and gradient plots in MatLab is slightly more complicated than making simple line graphs, but we will present some examples that, with simple modifications, should enable you to create most of the pictures that you will need. Here, I want the index 4 1, in some form, back. Using the MATCH function in Excel - find a match in a list without duplicates. , cost of carry) minus the relevant stock dividends occurring during the futures' duration, which is the time from the given date (which is usually today and, for this web page, is the "for" date listed under the page title) until the futures' settlement (expiration) date. The 'find' command only returns the indices of all the non-zero elements of a matrix. The find function (in its most fundamental application) locates all non-zero entries in its argument. The regexp function works the same way as strfind but instead of looking for strings literally, it tries to find matches within the cell array of strings using regular expressions. I cannot speak to the value of generally knowing how this is used in other professions. The negative outlook signals in part Moody's rising concern that the government will not find the political capital to implement the range of measures it intends, and that its plans will be largely ineffective in lifting growth. Impurities are added to each layer to create a specific electrical positive or negative charged behavior. Here are the ten companies burned the worst by negative news. Learn more about search, find MATLAB Answers. Use a mask to find all the entries in the vector x that are between -0. One ROC Curve and Cutoff Analysis Introduction This procedure generates empirical (nonparametric) and Binormal ROC curves. The list is not sorted alphabetically. Matlab or any other simulation softwares process everything in digital i. % Functions are also m-files. Find Index of maximum Value and maximum Value of a vector. In matlab, the postive and negative infinity symbols are named as inf and –inf respectively. These properties make JSON an ideal data-interchange language. m" extension containing Matlab % commands. 1448 yourArray(index) = rand index = index + 1; end. You can try out the differences of MATLAB vs Python with this example: >>>. Other supported data objects. There is also a version of the Final Value Theorem for discrete-time systems. Use a mask to find all the entries in the vector x that are between -0. The command linspace(a, b, n) creates n equally spaced points between a and b, including both a and b. For example, if a coefficient = decimal 5 multiplies input x,. You can check each y value to see if it's greater than (or less than) both neighbouring values. Request homework help for all sciences and math. To find the value of the third variable, plug your other two values into any of the three original equations, and solve for the third variable. m computes the real roots of a cubic. The list is not sorted alphabetically. It compiles and runs on a wide variety of UNIX platforms, Windows and MacOS. Index 44 1 Introduction 1. 81787768047 4 4868. Play Guess The Number online, here. To properly calculate the total power using ò P(f)df (should one choose to do so), it is necessary to divide each of the spectral values in W/kg/FFT pt. Matlab will automatically figure out how many entries you need and their values. Negative predictive value: If a test subject has a negative screening test, what is the probability that the subject really does not have the disease? In the same example, there were 63,895 subjects whose screening test was negative, and 63,650 of these were, in fact, free of disease. A statement in the switch block can be labeled with one or more case or default labels. The MATLAB programming language is a matrix-based language which allows matrix manipulations, plotting of functions and data, implementation of algorithms, creation of user interfaces, and interfacing with programs written in other languages,. and I want to get rid of rows with negative numbers in them. To generate a series of numbers from 10 to 50, incrementing by 5, use. If you are using MATLAB/OCTAVE interface, svmpredict can directly give you decision values. In MATLAB, a scalar is a variable with one row and one column. Find index of same values in array. Then the values of each input factor within its defined range should be changed during a run. For example (3 & 4) in NumPy is 0, while in Matlab both 3 and 4 are considered logical true and (3 & 4) returns 1. 5 = 100 deltas. Unary function that accepts an element in the range as argument and returns a value convertible to bool. Notes: When n = 2 an nth root is called a square root. 19252807406 and. As far as I aware there is no function doing this for you. a=[1 2 3 1] Discover what MATLAB. My guess is that you want to iterate in that cell, and probably what people is suggeting you ( create a normal array) is the best way to approach. Integers Integer Classes. k = find(X) returns the indices of the array X that point to nonzero elements. For the corresponding column vector simply replace the commas with semi-colons. There is no typographical difference in appearance between numerical variables and string variables. 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. You can try out the differences of MATLAB vs Python with this example: >>>. Under Windows, this may be easily done by using the path editing menu. Use the Matlab find function to find the index of the first three entries in the array x. Using the MATCH function in Excel - find a match in a list without duplicates. MATLAB (Matrix Laboratory) is a programming platform developed by MathWorks, which uses it's proprietary MATLAB programming language. minCoeff(). Wilson, Bruce Miller, Maria Luisa Gorno Tempini, and Shrikanth S. I have tried to use the find command and doing find(Y==0) but because in the array there is no exact zero number (goes to 0. A vector is a matrix with only one row or only one column. Learn more about matlab, array, find, indexing, index MATLAB. 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. Separating similar documents is sometimes worse than putting pairs of dissimilar documents in the same cluster. This is NOT something that the user can vary. The strcmp function takes two input arguments (two strings) and returns either true or false, just like any boolean expression. Although simple 8-bit integers or vectors of 8-bit integers are the most common sorts of pixel values used, some image formats support different types of value, for instance 32-bit signed integers or floating point values. These parts have wattage ratings. raise 10 to any power, positive or negative the result is always positive Log is the inverse of this, trying to find the log of a negative number is exactly like trying to find an index that when 10 is raised to it you get a negative answer. Note that +1 indicates a perfect fit (the paired values lie on a straight line) with a positive slope, while -1 indicates a perfect fit with a negative slope. Based on porous silicon (PSi) microarray images, we propose a new method called the phagocytosis algorithm (PGY) for removing the influence of speckle noise on image gray values. The chapter also introduces methods by which one can create and present visual stimuli of any kind on the screen. Other useful commands: fread, fprintf. All other things equal, researchers desire lower levels of VIF, as higher levels of VIF are known to affect adversely the results associated with a multiple. Also it's very easy to do this without the statiscs toolbox. Analysis Index Example of the Power method with Matlab function [vec,value]=power(start,A,toler) % %Power method for. MATLAB (Matrix Laboratory) is a programming platform developed by MathWorks, which uses it's proprietary MATLAB programming language. If the energy value is greater than the threshold value a counter is incremented. Note that values are negative in the compressive case. In this published M-file, we will use MATLAB to solve problems about lines and planes in three-dimensional space. I cannot speak to the value of generally knowing how this is used in other professions. The mathematical content corresponds to chapter 11 of the text by Gulick and Ellis. Impurities are added to each layer to create a specific electrical positive or negative charged behavior. But if you really need to do it this way, here is a code that will do the work: clear; clc;. MATLAB Answers. If you have not received a response within two business days, please send your inquiry again or call (314) 444-3733. Im plotting a graph of X against Y and i want to know the value of X when Y = 0. For example, if a coefficient = decimal 5 multiplies input x,. It might be the case that if the values in the matrix were restricted to a certain range that it would always be possible, at least for certain matrix orders. How to Find Position of First Negative Value in List? How can I set up a formula to find the position of the first negative (or text) value in a list? I have a list of values (let's say in cells A1:A20) that can be positive, zero, negative, or the text "END" (indicating the end of the list if there are fewer than 20 values). When the radius is negative: When graphing a polar coordinate with a negative radius, you move from the pole in the direction opposite the given positive angle (on the same line as the given angle but in the direction opposite to the angle from the pole). The default is full. peakdet: Peak detection using MATLAB Here's a problem I encounter in several fields: Find the local maxima and minima in some noisy signal, which typically looks like the following graph: The local maxima and minima are plotted as red and green stars on the graph. Matlab treats any non-zero value as 1 and returns the logical AND. Matlab, find index of minimum value with the condition that it must be negative. find all elements in the array a that has value 1 or 2). The fact-checkers, whose work is more and more important for those who prefer facts over lies, police the line between fact and falsehood on a day-to-day basis, and do a great job. Today, my small contribution is to pass along a very good overview that reflects on one of Trump’s favorite overarching falsehoods. Namely: Trump describes an America in which everything was going down the tubes under  Obama, which is why we needed Trump to make America great again. And he claims that this project has come to fruition, with America setting records for prosperity under his leadership and guidance. “Obama bad; Trump good” is pretty much his analysis in all areas and measurement of U.S. activity, especially economically. Even if this were true, it would reflect poorly on Trump’s character, but it has the added problem of being false, a big lie made up of many small ones. Personally, I don’t assume that all economic measurements directly reflect the leadership of whoever occupies the Oval Office, nor am I smart enough to figure out what causes what in the economy. But the idea that presidents get the credit or the blame for the economy during their tenure is a political fact of life. Trump, in his adorable, immodest mendacity, not only claims credit for everything good that happens in the economy, but tells people, literally and specifically, that they have to vote for him even if they hate him, because without his guidance, their 401(k) accounts “will go down the tubes.” That would be offensive even if it were true, but it is utterly false. The stock market has been on a 10-year run of steady gains that began in 2009, the year Barack Obama was inaugurated. But why would anyone care about that? It’s only an unarguable, stubborn fact. Still, speaking of facts, there are so many measurements and indicators of how the economy is doing, that those not committed to an honest investigation can find evidence for whatever they want to believe. Trump and his most committed followers want to believe that everything was terrible under Barack Obama and great under Trump. That’s baloney. Anyone who believes that believes something false. And a series of charts and graphs published Monday in the Washington Post and explained by Economics Correspondent Heather Long provides the data that tells the tale. The details are complicated. Click through to the link above and you’ll learn much. But the overview is pretty simply this: The U.S. economy had a major meltdown in the last year of the George W. Bush presidency. Again, I’m not smart enough to know how much of this was Bush’s “fault.” But he had been in office for six years when the trouble started. So, if it’s ever reasonable to hold a president accountable for the performance of the economy, the timeline is bad for Bush. GDP growth went negative. Job growth fell sharply and then went negative. Median household income shrank. The Dow Jones Industrial Average dropped by more than 5,000 points! U.S. manufacturing output plunged, as did average home values, as did average hourly wages, as did measures of consumer confidence and most other indicators of economic health. (Backup for that is contained in the Post piece I linked to above.) Barack Obama inherited that mess of falling numbers, which continued during his first year in office, 2009, as he put in place policies designed to turn it around. By 2010, Obama’s second year, pretty much all of the negative numbers had turned positive. By the time Obama was up for reelection in 2012, all of them were headed in the right direction, which is certainly among the reasons voters gave him a second term by a solid (not landslide) margin. Basically, all of those good numbers continued throughout the second Obama term. The U.S. GDP, probably the single best measure of how the economy is doing, grew by 2.9 percent in 2015, which was Obama’s seventh year in office and was the best GDP growth number since before the crash of the late Bush years. GDP growth slowed to 1.6 percent in 2016, which may have been among the indicators that supported Trump’s campaign-year argument that everything was going to hell and only he could fix it. During the first year of Trump, GDP growth grew to 2.4 percent, which is decent but not great and anyway, a reasonable person would acknowledge that — to the degree that economic performance is to the credit or blame of the president — the performance in the first year of a new president is a mixture of the old and new policies. In Trump’s second year, 2018, the GDP grew 2.9 percent, equaling Obama’s best year, and so far in 2019, the growth rate has fallen to 2.1 percent, a mediocre number and a decline for which Trump presumably accepts no responsibility and blames either Nancy Pelosi, Ilhan Omar or, if he can swing it, Barack Obama. I suppose it’s natural for a president to want to take credit for everything good that happens on his (or someday her) watch, but not the blame for anything bad. Trump is more blatant about this than most. If we judge by his bad but remarkably steady approval ratings (today, according to the average maintained by 538.com, it’s 41.9 approval/ 53.7 disapproval) the pretty-good economy is not winning him new supporters, nor is his constant exaggeration of his accomplishments costing him many old ones). I already offered it above, but the full Washington Post workup of these numbers, and commentary/explanation by economics correspondent Heather Long, are here. On a related matter, if you care about what used to be called fiscal conservatism, which is the belief that federal debt and deficit matter, here’s a New York Times analysis, based on Congressional Budget Office data, suggesting that the annual budget deficit (that’s the amount the government borrows every year reflecting that amount by which federal spending exceeds revenues) which fell steadily during the Obama years, from a peak of $1.4 trillion at the beginning of the Obama administration, to $585 billion in 2016 (Obama’s last year in office), will be back up to $960 billion this fiscal year, and back over $1 trillion in 2020. (Here’s the New York Times piece detailing those numbers.) Trump is currently floating various tax cuts for the rich and the poor that will presumably worsen those projections, if passed. As the Times piece reported: