File: props.sh 1 #!/bin/sh 2 3 # The MIT License (MIT) 4 # 5 # Copyright © 2024 pacman64 6 # 7 # Permission is hereby granted, free of charge, to any person obtaining a copy 8 # of this software and associated documentation files (the “Software”), to deal 9 # in the Software without restriction, including without limitation the rights 10 # to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 11 # copies of the Software, and to permit persons to whom the Software is 12 # furnished to do so, subject to the following conditions: 13 # 14 # The above copyright notice and this permission notice shall be included in 15 # all copies or substantial portions of the Software. 16 # 17 # THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 18 # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 19 # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 20 # AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 21 # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 22 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 23 # SOFTWARE. 24 25 26 # props [x] [y...] 27 # 28 # Show various PROPortionS involving 2 numbers; when given only 1 number, 29 # show its inverse. 30 31 32 # handle help options 33 case "$1" in 34 -h|--h|-help|--help) 35 # show help message, extracting the info-comment at the start 36 # of this file, and quit 37 awk '/^# +props/, /^$/ { gsub(/^# ?/, ""); print }' "$0" 38 exit 0 39 ;; 40 esac 41 42 awk ' 43 BEGIN { 44 if (ARGC < 2 || ARGV[1] + 0 == 0) { 45 print "props [x] [y...]"; 46 print ""; 47 print "Show various PROPortionS involving 2 numbers; 48 print "when given only 1 number, show its inverse."; 49 exit(1); 50 } 51 52 # handle the 1-number case 53 if (ARGC == 2) { 54 x = ARGV[1] + 0.0; 55 printf("x = %f\n", x); 56 printf("1 / x ~= %f\n", div(1, x)); 57 exit(0); 58 } 59 60 # get values and sort them 61 x = ARGV[1] + 0.0; # min 62 y = ARGV[2] + 0.0; # max 63 delete ARGV[1]; 64 delete ARGV[2]; 65 if (x > y) { 66 temp = x; 67 x = y; 68 y = temp; 69 } 70 71 printf("min: x = %f\n", x); 72 printf("max: y = %f\n", y); 73 # printf("sum: %f\n", x + y); 74 # printf("diff: %f\n", y - x); 75 # printf("avg: %f\n", (x + y) / 2); 76 print; 77 printf(" x / y ~= %f\n", div(x, y)); 78 printf("1 - (x / y) ~= %f\n", div(y - x, y)); 79 printf(" y / x ~= %f\n", div(y, x)); 80 print; 81 printf("x / (x + y) ~= %f\n", div(x, x + y)); 82 printf("y / (x + y) ~= %f\n", div(y, x + y)); 83 print; 84 printf("x / (y - x) ~= %f\n", div(x, y - x)); 85 printf("y / (y - x) ~= %f\n", div(y, y - x)); 86 # printf("(y - x) / y ~= %f\n", div(y - x, y)); 87 } 88 89 function div(a, b) { 90 if (b != 0) { 91 return a / b; 92 } 93 return (a >= 0 ? "+inf" : "-inf") + 0; 94 } 95 ' "$@"