What to do if you don t define a function that corresponds to an input parameter of type double

This is that this function is not a system function, but a custom function.

The imread function is used to read various image files, and its general usage is [x,map]=imread('filename','fmt'), where x and map are the read image data and color table data, respectively, fmt is the format of the image, and filename is the read image file (you can add the path of the file).

Example: [x,map]=imread(',tif'); Comparing the characteristics of reading x and map of binary images, grayscale images, index images, and color images, you can use the size function to display the dimensions of the array and understand the characteristics of the data.

The fourier function will be canceled in the future, only the old version of matlab can still be used, of course, it is not impossible to use, the current fourier function requires the input to be sym type to use, help

Fourier will show undefined functions, you need helpsym fourier to see the usage, now use the FFT function more.

The limit command is for equations with variables, but not for numerical values, such as limit(sin(x),x,0).

The result is: ans

However, limit(10) is meaningless, cannot be operated, and there will be an error message.

1. A simple c

Language**, whose function is to receive one.

double

type variable input, and output the received value.

2. Compile the program, and there is no compilation error.

3. However, when running the program, an error occurred.

4. Therefore, when we need to receive.

double

The type variable should be specified when entered.

The following is the correct ** after the change. After the change, the program will work normally.

I'm just about to count a number, I hope it will be helpful to people in the future:

The topic of my calculation is:

syms x;

cp=;f=int(cp*exp((-x-200e-7).^2))./(2*(51*51e-14)))x,50e-7,400e-7)

double(f)

Explanation: cp*exp((-x-200e-7)^2)).(2*(51*51e-14))) This part is the formula to be calculated, i.e., fx

The second is that the variable means x.

The third and fourth variables are the upper and lower bounds of x, i.e., the integral intervals.

double(f) is the result of the conversion to double-type syms x; is the most important statement, which means that x is a variable.

The int function is malformed, there is no independent variable, and I don't know what variable to integrate.

You may not have saved the file name as the function name, i.e. the file name must match the function name. And make sure that the function name file has been added to the library, which can be added in the "Set Path".

It's just that this function is not a system function, but a custom function, and you don't have this function file.

You turn the position number v into an array, int can't use a set of arrays to integrate the function, you just need to provide the upper and lower limits of v.

The changes are as follows: You can see the usage of int in MATLAB.

There is an error when the MATLAB program is running, and the wrong operation method is found

For beginners, when developing MATLAB programs, there are often many errors. If an error occurs while a MATLAB program is running, it can be located and found by the appropriate method, as listed below.

In the following method description, the following example procedure is used to illustrate;

After the program runs incorrectly, switch to the MATLAB command line, observe the error message in the command line, and determine the cause of the error.

3.In the error message, find the number of lines with error ** in the source program, and click the number of lines link to directly locate the error statement;

4.After the error statement is located, it will automatically jump to the ** device, and identify the location of the wrong ** by cursor in the ** device;

5.After the error statement is determined, use the F12 shortcut key to set the breakpoint at the error statement.

6.After the breakpoint setting is completed, re-execute the program through the F5 shortcut key, and the program will stop running at the breakpoint and enter the debugging state;

7.There are multiple steps in the debug state to find the cause of a program problem.

1. A simple C language** whose function is to receive a double-type variable input and output the received value.

2. Compile the program, and there is no compilation error.

3. However, when running the program, an error occurred.

4. Therefore, when we need to receive input for a double-type variable, we should specify %lf.

5. The following is the correct ** after the change. After the change, the program will work normally.

The current running directory should be the directory where the function yunshuann is saved.

Otherwise, it can't be called correctly.

Follow-up question: How can I set the directory where the bit functions are located in the running directory of MATLAB? Can you give an example, thank you?

There is a directory to select at the top of the command line window.

After you make a selection, you can see your function in the current folder on the left, and you can call it.

Fourier this function will be canceled in the future, only the old version of MATLAB can still be used, of course, it is not impossible to use, the current fourier function requires the input to be sym type to use, help fourier will show the undefined function, need help sym fourier to see the usage, now use the FFT function more.

The limit command is for equations with variables, but not for numerical values, such as limit(sin(x),x,0).

The result is: ans = 0.

However, limit(10) is meaningless, cannot be operated, and there will be an error message.