some tips and tricks

Table of Contents

1 Mathematics

1.1 \(\Pi\) Calculation

echo "scale=40; 4*a(1)" | bc -l -q

You can get a more accurate \(\Pi\) value by increasing "scale" value.

echo "obase=16;ibase=10;15" | bc

2 Power Tools

2.1 Development

strings
print the strings of printable characters in files. You can read strings in ELF files or libraries by it.

2.2 merge pdf files into one file

gs -q -dNOPAUSE -sDEVICE=pdfwrite -sOUTPUTFILE=output.pdf -dBATCH a.pdf b.pdf


Last Updated by Bao Hexing (HexingB@qq.com)