Assessment wanted: functions 3

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#1

Hi everyone. I will really appreciate your feedback on the answer I have provided to this assessment.

Here’s my solution for functions 3: https://codepen.io/coddysey/pen/pogZYpM

Here’s the assessment: https://developer.mozilla.org/en-US/docs/Learn/JavaScript/Building_blocks/Test_your_skills:_Functions

#2

Reading your source code, I believe that it will sometimes print undefined instead of a first name. Am I wrong?

#3

Thanks @yoric. I tested it several times and never got such result. Where do you think the bug might be?

#4

If you look at random(min, max), you can determine that the result can be any value between min (included) and max (included).

Consequently, random(0, names.length) can be any value between 0 (included) and names.length (included).

Now, names[0] is 'Chris'. But what is names[names.length]?

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#5

names.length is the length of the array which is in this case the last item in the array would therefore return a value of ‘jada’

#6

Are you sure?

To check this out, you could open the DevTools, go to the console and write

let names = ['Chris', 'Li Kang', 'Anne', 'Francesca', 'Mustafa', 'Tina', 'Bert', 'Jada'];
names[names.length]
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#7

I agree with Yoric, console.log(names[names.length-1]); will give the right result.

#8

Oooops. Thanks a bunch, I will fix the code

#9

thanks for the feedback

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#10

Hey guys, I was having trouble with this task, so came here for help. seeing this brought up another question of why is the -1 required in names[names.length-1].
and tested and see that it does work, but why cant you just set names.length??

thanks for any replies, I am eager to understand :slight_smile:

#11

using the example below in your console:

let names = ['Chris', 'Li Kang', 'Anne', 'Francesca', 'Mustafa', 'Tina', 'Bert', 'Jada'];
console.log(names.length) // 8.

Remember that arrays are initiated from zero i.e
index0 - Chris;
index1 - Li Kang;
index2 - Anne;
index3 - Francesca;
index4 - Mustafa;
index5 - Tina;
index6 - Bert;
index7 - Jada

The index of the last character in the array equals 7. This means that the length of the array is always 1 more than the last character of the array. So, if I typed
console.log(names[names.length])//undefined because there is no 8th character in the array. If I typed
console.log(names[names.length -1])//Jada
it would return the last character.

I hope this help you understand.

#12

hey so, if im understanding this right

names[names.length] does not take into account that the index starts at 0?

so we need to adjust the length we want searched to take that into account?

sorry, I just thought that the length method would already take that it starts from 0 it into account since there are 8 items in the Array.

Thank you for your reply :slight_smile:

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