# Posts

### Repeated eigenvalues

If a matrix has repeated eigenvalues, the eigenvectors of the matched repeated eigenvalues become one of eigenspace. For example, the …

### Linear transformation

A norm of linear transformation $$\Lambda : X \rightarrow Y$$ is defined by \(\| \Lambda \| = \sup \{ \| \Lambda(x) \|:x \in X, \|x\| …

### Convergence

It is the main subject of analysis that finding conditions making sequential mathematical objects like a set, sequence, series to be …

### Laplace transformation

The Fourier series represents a periodic function as a descrete vectors. The Fourier transformation turns a time domain non-periodic …

### Use Korean font in pdf generated from rmarkdown on Windows

yaml --- mainfont: NanumGothic output: pdf_document: latex_engine: xelatex --- The mainfont is the LaTex option. The argument is a font …

### Convolution and Fourier transformation

Convolution is a vector operation on two vectors. \[ Convolution \\ c * d = d*c \\ (c*d)_n = \Sigma_{i+j} c_i d_j = \Sigma_i c_i …