Reputation: 133
I have a problem. I'm studying javascript but I have no idea how to create tables working only on javascript files. I have to create a table for each output of letter frequency but I have no idea how to do it. Here is the output I should have to have:
At the beginning I thought to work on the HTML but I can't as that part is related to test my code has to pass. Here I will show some of them:
display_letter_frequency(letter_frequency("Hello"),document.getElementById("frequency_table"));
var rows = document.getElementById("frequency_table").querySelectorAll('tr')
equal(rows.length, 4, "With input String 'Hello' there should be 4 table rows")
equal(rows[0].querySelectorAll('td')[0].innerHTML, 'H', "1st td of 1st tr should have the value H");
equal(rows[0].querySelectorAll('td')[1].innerHTML, '1', "2nd td of 1st tr should have the value 1");
equal(rows[1].querySelectorAll('td')[0].innerHTML, 'E', "1st td of 2nd tr should have the value E");
equal(rows[1].querySelectorAll('td')[1].innerHTML, '1', "2nd td of 2nd tr should have the value 1");
equal(rows[2].querySelectorAll('td')[0].innerHTML, 'L', "1st td of 3rd tr should have the value L");
equal(rows[2].querySelectorAll('td')[1].innerHTML, '2', "2nd td of 3rd tr should have the value 2");
equal(rows[3].querySelectorAll('td')[0].innerHTML, 'O', "1st td of 4th tr should have the value O");
equal(rows[3].querySelectorAll('td')[1].innerHTML, '1', "2nd td of 4th tr should have the value 1");
Also I cannot use the console.log but write just the code of the function that will be called back by the tester. Here is what I did but I don't know if it's right and how to go forward:
function display_letter_frequency(a,dom) {
if(a === undefined){
return undefined
} else {
var tbl = document.createElement("table");
var tblBody = document.createElement("tbody");
for(var x in a){
var row = document.createElement("tr");
}
}
}
This code is related to a function I wrote before which count in command line the frequency letters of the user:
function letter_frequency(s) {
if(s === undefined){
return undefined
} else {
var freq = {};
for (var i = 0; i < s.length; i++) {
var character = s.charAt(i).toUpperCase();
if (freq[character]) {
freq[character]++;
} else {
freq[character] = 1;
}
}
}
return freq;
}
Hope that the problem is clear and you can help me and the people who will need it. I looked around the web and they talks about some frequency table to define my problem. I don't know if t's right
Upvotes: 2
Views: 524
Reputation: 432
Check this - > http://jsfiddle.net/sumeetp1991/tqdxjk0d/1/
/* javascript */
var my_val = "asdasd";
var obj = getFrequency(my_val);
var table = document.createElement("table");
Object.keys(obj).forEach(function(key) {
var tr = document.createElement("tr");
var td_key = document.createElement("td");
var txt_key = document.createTextNode(key);
td_key.appendChild(txt_key);
var td_val = document.createElement("td");
var txt_val = document.createTextNode(obj[key]);
td_val.appendChild(txt_val);
tr.appendChild(td_key);
tr.appendChild(td_val);
table.appendChild(tr);
});
document.getElementById("table").appendChild(table);
function getFrequency(string) {
var freq = {};
for (var i=0; i<string.length;i++) {
var character = string.charAt(i);
if (freq[character]) {
freq[character]++;
} else {
freq[character] = 1;
}
}
return freq;
}
/* html */
<div id="table">
</div>
/* CSS */
td
{
border: 1px solid black;
}
Upvotes: 0
Reputation: 3816
Try
for(var x in a){
var row = document.createElement("tr");
letterCell = document.createElement('td');
freqCell = document.createElement('td');
letterCell.innerHTML = x;
freqCell.innerHTML = a[x];
row.appendChild(letterCell);
row.appendChild(freqCell);
tblBody.appendChild(row);
}
}
(Not tested)
Upvotes: 1