Tricky Problems in MATLAB

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1. Sometimes you might find that you can use some built-in function in MATLAB at first, but later you cannot use it any. If so, you should probably check whether you are doing parallel computing in MATLAB. Parallel computing in MATLAB can cause some problem. What you can do is to use other functions that MATLAB accept in parallel computing to replace these which result in problems.

2. dlmwrite is convenient to write vector and matrix data to a file, but it might lose accuracy especially when you do not specify the accuracy attribute. So do not use dlmwrite to write data into text files when you works with high accuracy data, instead, you can use binary data.

3. + has priority over : in MATLAB which is different from R.

4. When MATLAB starts, it set the random number generator to the default one and set the seed to be the default seed. So if you run a simulation, reboot MATLAB and run the same simulation, you will get the same results.

5. Since most arithmetic objects in MATLAB are matrices, arithmetic operations in MATLAB are basically matric operations. So +, -, \*, / are matrix addition operator, matrix subtraction operator, matrix multiplication operator and matrix division operator respectively. Notice that / is also called right matrix division operator. Suppose B/A=X, it means that XA=B. There is also another matrix division operator \(\backslash\). Suppose \(B\backslash A=X\), it means that AX=B. If you want to perform element wise operation rather than matrix operations, you have to put an extra dot (i.e. .) before the corresponding matrix operators.