Author Archives: Linuxgal

Skyglobe for MSDOS, still the best astronomy software 35 years later… Before we wasted time on Windows solitaire we wasted time on MSDOS solitaire.

while :;do echo $LINES $COLUMNS $((RANDOM%COLUMNS)) $(printf ‘%b’ “\\u$(printf ‘%04x’ $((RANDOM%500)))”);sleep .05;done|gawk ‘{a[$3]=0;for(x in a){o=a[x];a[x]++;printf “\033[%s;%sH\033[2;32m%s”,o,x,$4;printf “\033[%s;%sH\033[1;37m%s\033[0;0H”,a[x],x,$4;if(a[x]>=$1)a[x]=0}}’

Imagemagick showcolor() { display -size 300×300 xc:”#${1}”; } showcolor fba9c3 &

Generate magic squares for any odd side length: #!/usr/bin/env python3 import sys def magic_constant(n): return n * (n * n + 1) // 2 def magic_square(n): square = [[0] * n for _ in range(n)] num = 1 i, j … Continue reading →

Print a list of last Fridays every month for the given year #!/usr/bin/python3 import sys from calendar import monthrange from datetime import date, timedelta def last_fridays(year): for month in range(1, 13): last_day = date(year, month, monthrange(year, month)[1]) yield last_day – … Continue reading →

Perfect #include <stdio.h> int main(void) { for (unsigned int p = 2; p <= 23; p++) { unsigned long long m = (1ULL << p) – 1; int prime = 1; for (unsigned long long i = 2; i * … Continue reading →

Print a list of antiprimes (highly composite numbers) with bc #! /usr/bin/bc define factors(n) { auto c, i for(i=1;i<=n;i++) { if(n%i==0) c+=1 } return c } max = 0 n = 1 for(c=19; c > 0;) { f = factors(n) … Continue reading →

Combinations of r elements chosen from a pool of n elements BEGIN { for (i=1; i <= r; i++) { A[i] = i if (i < r ) printf i OFS else print i} while (A[1] < n – r … Continue reading →

Hex #!/usr/bin/python3 import sys with open(sys.argv[1], “rb”) as f: data = f.read() for offset in range(0, len(data), 16): b = data[offset:offset + 16] left = ” “.join(f”{x:02x}” for x in b[:8]) right = ” “.join(f”{x:02x}” for x in b[8:]) hexpart … Continue reading →