{"id":706,"date":"2020-12-29T16:52:26","date_gmt":"2020-12-29T16:52:26","guid":{"rendered":"https:\/\/web.htk.tlu.ee\/digitaru\/tarkvara2\/?post_type=chapter&#038;p=706"},"modified":"2020-12-29T16:53:33","modified_gmt":"2020-12-29T16:53:33","slug":"andmete-lugemine-ja-kirjutamine","status":"publish","type":"chapter","link":"https:\/\/web.htk.tlu.ee\/digitaru\/tarkvara2\/chapter\/andmete-lugemine-ja-kirjutamine\/","title":{"raw":"Andmete lugemine ja kirjutamine","rendered":"Andmete lugemine ja kirjutamine"},"content":{"raw":"<h2>Andmete lugemine failist<\/h2>\r\nAndmete anal\u00fc\u00fcsimisel on sageli vaja andmed lugeda failist. Ilmselt k\u00f5ige sagedasem tekstifaili formaat, mida andmeanal\u00fc\u00fcsis kasutatakse, on CSV. Pandas pakub CSV failide lugemiseks funktsiooni <code class=\"EnlighterJSRAW\" data-enlighter-language=\"python\" data-enlighter-theme=\"bootstrap4\">read_csv<\/code>, mis tagastab andmefreimi. Loeme andmed Euroopa kasvuhoonegaaside emissiooni kohta. Andmed on failist <a href=\"http:\/\/kodu.ut.ee\/~merka123\/plotly\/kasvuhoonegaasid.csv\">kasvuhoonegaasid.csv<\/a> (allikas Eurostat). Lisame juurde ka failikodeeringu UTF-8 ja andmete eraldajaks on semikoolon (;).\r\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"python\" data-enlighter-theme=\"bootstrap4\" data-enlighter-linenumbers=\"false\">andmed = pd.read_csv('kasvuhoonegaasid.csv', encoding='UTF-8', sep=';')<\/pre>\r\n<span style=\"background-color: #f1c232\">\u00a0! <\/span><span style=\"background-color: #fff2cc\">\u00a0CSV failis ei tohi olla veeru nimedes t\u00fchikuid, need tuleb asendada _ -ga (alakriipsuga). N\u00e4iteks Keskmine hinne \u2192 Keskmine_hinne.<\/span>\r\n\r\n<span style=\"background-color: #fff2cc\">Sama funktsiooniga on v\u00f5imalik ka andmed veebist lugeda. Faili nime asemel tuleb kasutada veebilinki, kus andmed asuvad.<\/span>\r\n\r\n&nbsp;\r\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"python\" data-enlighter-theme=\"bootstrap4\" data-enlighter-linenumbers=\"false\">andmed = pd.read_csv('http:\/\/kodu.ut.ee\/~merka123\/plotly\/kasvuhoonegaasid.csv', encoding='UTF-8', sep=';')<\/pre>\r\n<h2>Andmete kirjutamine faili<\/h2>\r\nKui andmed on t\u00f6\u00f6deldud, v\u00f5ib tekkida vajadus need uude faili kirjutada. Seda saab teha funktsiooni <code class=\"EnlighterJSRAW\" data-enlighter-language=\"python\" data-enlighter-theme=\"bootstrap4\">.to_csv<\/code> abil. Kirjutame muudetud andmed faili nimega <code class=\"EnlighterJSRAW\" data-enlighter-language=\"python\" data-enlighter-theme=\"bootstrap4\">uued_andmed.csv<\/code>, kasutame eraldajana semikoolonit.\r\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"python\" data-enlighter-theme=\"bootstrap4\" data-enlighter-linenumbers=\"false\">andmed.to_csv('uued_andmed.csv', sep=';', encoding='utf-8')<\/pre>","rendered":"<h2>Andmete lugemine failist<\/h2>\n<p>Andmete anal\u00fc\u00fcsimisel on sageli vaja andmed lugeda failist. Ilmselt k\u00f5ige sagedasem tekstifaili formaat, mida andmeanal\u00fc\u00fcsis kasutatakse, on CSV. Pandas pakub CSV failide lugemiseks funktsiooni <code class=\"EnlighterJSRAW\" data-enlighter-language=\"python\" data-enlighter-theme=\"bootstrap4\">read_csv<\/code>, mis tagastab andmefreimi. Loeme andmed Euroopa kasvuhoonegaaside emissiooni kohta. Andmed on failist <a href=\"http:\/\/kodu.ut.ee\/~merka123\/plotly\/kasvuhoonegaasid.csv\">kasvuhoonegaasid.csv<\/a> (allikas Eurostat). Lisame juurde ka failikodeeringu UTF-8 ja andmete eraldajaks on semikoolon (;).<\/p>\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"python\" data-enlighter-theme=\"bootstrap4\" data-enlighter-linenumbers=\"false\">andmed = pd.read_csv('kasvuhoonegaasid.csv', encoding='UTF-8', sep=';')<\/pre>\n<p><span style=\"background-color: #f1c232\">\u00a0! <\/span><span style=\"background-color: #fff2cc\">\u00a0CSV failis ei tohi olla veeru nimedes t\u00fchikuid, need tuleb asendada _ -ga (alakriipsuga). N\u00e4iteks Keskmine hinne \u2192 Keskmine_hinne.<\/span><\/p>\n<p><span style=\"background-color: #fff2cc\">Sama funktsiooniga on v\u00f5imalik ka andmed veebist lugeda. Faili nime asemel tuleb kasutada veebilinki, kus andmed asuvad.<\/span><\/p>\n<p>&nbsp;<\/p>\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"python\" data-enlighter-theme=\"bootstrap4\" data-enlighter-linenumbers=\"false\">andmed = pd.read_csv('http:\/\/kodu.ut.ee\/~merka123\/plotly\/kasvuhoonegaasid.csv', encoding='UTF-8', sep=';')<\/pre>\n<h2>Andmete kirjutamine faili<\/h2>\n<p>Kui andmed on t\u00f6\u00f6deldud, v\u00f5ib tekkida vajadus need uude faili kirjutada. Seda saab teha funktsiooni <code class=\"EnlighterJSRAW\" data-enlighter-language=\"python\" data-enlighter-theme=\"bootstrap4\">.to_csv<\/code> abil. Kirjutame muudetud andmed faili nimega <code class=\"EnlighterJSRAW\" data-enlighter-language=\"python\" data-enlighter-theme=\"bootstrap4\">uued_andmed.csv<\/code>, kasutame eraldajana semikoolonit.<\/p>\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"python\" data-enlighter-theme=\"bootstrap4\" data-enlighter-linenumbers=\"false\">andmed.to_csv('uued_andmed.csv', sep=';', encoding='utf-8')<\/pre>\n","protected":false},"author":16,"menu_order":10,"template":"","meta":{"pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":[],"pb_section_license":""},"chapter-type":[],"contributor":[],"license":[],"class_list":["post-706","chapter","type-chapter","status-publish","hentry"],"part":93,"_links":{"self":[{"href":"https:\/\/web.htk.tlu.ee\/digitaru\/tarkvara2\/wp-json\/pressbooks\/v2\/chapters\/706","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/web.htk.tlu.ee\/digitaru\/tarkvara2\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/web.htk.tlu.ee\/digitaru\/tarkvara2\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/web.htk.tlu.ee\/digitaru\/tarkvara2\/wp-json\/wp\/v2\/users\/16"}],"version-history":[{"count":1,"href":"https:\/\/web.htk.tlu.ee\/digitaru\/tarkvara2\/wp-json\/pressbooks\/v2\/chapters\/706\/revisions"}],"predecessor-version":[{"id":708,"href":"https:\/\/web.htk.tlu.ee\/digitaru\/tarkvara2\/wp-json\/pressbooks\/v2\/chapters\/706\/revisions\/708"}],"part":[{"href":"https:\/\/web.htk.tlu.ee\/digitaru\/tarkvara2\/wp-json\/pressbooks\/v2\/parts\/93"}],"metadata":[{"href":"https:\/\/web.htk.tlu.ee\/digitaru\/tarkvara2\/wp-json\/pressbooks\/v2\/chapters\/706\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/web.htk.tlu.ee\/digitaru\/tarkvara2\/wp-json\/wp\/v2\/media?parent=706"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/web.htk.tlu.ee\/digitaru\/tarkvara2\/wp-json\/pressbooks\/v2\/chapter-type?post=706"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/web.htk.tlu.ee\/digitaru\/tarkvara2\/wp-json\/wp\/v2\/contributor?post=706"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/web.htk.tlu.ee\/digitaru\/tarkvara2\/wp-json\/wp\/v2\/license?post=706"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}