I was working on a basic reverse mortgage calculator (input monthly payment, it returns how much you can afford). Not being a math wiz, I didn't spend too much time figuring out how to solve an equation that involves multiple variables, as well as some that are repeated.<\/p>\n
Instead, I opted for a brute force approach, running through hundreds of calculations, tweaking the parameters a little bit each time, until an expected outcome is reached (or comes close). After completing my "brute force loop", and running some tests, I was a little disappointed to find that only 400 calculations took 2.5 seconds to complete on Firefox 13.<\/p>\n
Then, it hit me, I was doing 3 DOM lookups with jQuery in each loop, i.e.<\/p>\n
\t \/\/ formula that uses param So, I was ecstatic, assuming that if I set a variable to the field values, outside of the for loop, I'll cut execution time dramatically.<\/p>\n I logged the time for both approaches, and much to my surprise, I only saved about 2 or 3% by dropping the DOM lookups.<\/p>\n Just thought I let everyone in on that, in case you are looking for ways to optimize your code – start somewhere else!<\/p>\n Oh, and as a little bonus, interesting to see how quickly different browsers run JS. My code was executed in the times listed below by browser:<\/p>\n \n\tFF 13: 2.5 seconds Nice going Google! I was working on a basic reverse mortgage calculator (input monthly payment, it returns how much you can afford). Not being a math wiz, I…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"amp_status":""},"categories":[5],"tags":[157],"_links":{"self":[{"href":"https:\/\/www.sitekickr.com\/blog\/wp-json\/wp\/v2\/posts\/668"}],"collection":[{"href":"https:\/\/www.sitekickr.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.sitekickr.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.sitekickr.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.sitekickr.com\/blog\/wp-json\/wp\/v2\/comments?post=668"}],"version-history":[{"count":1,"href":"https:\/\/www.sitekickr.com\/blog\/wp-json\/wp\/v2\/posts\/668\/revisions"}],"predecessor-version":[{"id":669,"href":"https:\/\/www.sitekickr.com\/blog\/wp-json\/wp\/v2\/posts\/668\/revisions\/669"}],"wp:attachment":[{"href":"https:\/\/www.sitekickr.com\/blog\/wp-json\/wp\/v2\/media?parent=668"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.sitekickr.com\/blog\/wp-json\/wp\/v2\/categories?post=668"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.sitekickr.com\/blog\/wp-json\/wp\/v2\/tags?post=668"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\n\tfor(var i = 0; i < 400; i++) {
\n\t \/\/ brute force stuff..
\n\t param = $(this).parent().parent().siblings('.myfield').val();
\n\t \/\/ more DOM lookups<\/p>\n
\n\t}
\n\t<\/code><\/p>\nvar param = $(this).parent().parent().siblings('.myfield').val();
\n\tfor(var i = 0; i < 400; i++) {
\n\t \/\/ brute force stuff..
\n\t \/\/ formula that uses param
\n\t}<\/code><\/p>\n
\n\tIE 9: 1.7 seconds
\n\tIE 8: 5.1 seconds
\n\tIE 7: 4.8 seconds (what did they do wrong in IE 8!)
\n\tChrome 19: 1.5 seconds
\n\tSafari 5.1 1.8 seconds<\/p>\n
\n\t <\/p>\n","protected":false},"excerpt":{"rendered":"