X-Git-Url: http://gitweb.michael.orlitzky.com/?p=octave.git;a=blobdiff_plain;f=has_root.m;h=ffd96666b0bca58366fc5b641c43a2893cf3b16c;hp=5c835d8e51e864e8d37a318059339e4d7e30c18e;hb=ba154db78b02163be343b235438e3add73cba526;hpb=78254b47cdaf395eac1e31845a2cc9edb55a4aca diff --git a/has_root.m b/has_root.m old mode 100755 new mode 100644 index 5c835d8..ffd9666 --- a/has_root.m +++ b/has_root.m @@ -1,5 +1,3 @@ -#!/usr/bin/octave --silent - function has_root = has_root(fa, fb) ## Use the intermediate value theorem to determine whether or not some ## function has an odd number of roots on an interval. If the function @@ -9,7 +7,19 @@ function has_root = has_root(fa, fb) ## Call the function whose roots we're concerned with 'f'. The two ## parameters `fa` and `fb` should correspond to f(a) and f(b). ## - + ## + ## INPUTS: + ## + ## * ``fa`` - The value of `f` at one end of the interval. + ## + ## * ``fb`` - The value of `f` at the other end of the interval. + ## + ## OUTPUTS: + ## + ## * ``has_root`` - True if we can use the I.V.T. to conclude that + ## there is a root on [a,b], false otherwise. + ## + ## If either f(a) or f(b) is zero, the product of their signs will be ## zero and either a or b is a root. If the product of their signs is ## negative, then f(a) and f(b) are non-zero and have opposite sign,