supz_k

Thanks for the all resources. I'm mainly looking for a mathematics-based approach. "How to solve it" looks promising. Thanks.

Thank you.

Thanks! That makes sense.

That's awesome. Did you have any musical training when you were little? (below 7 years)

This is RELATIVE pitch, which anyone can develop. Perfect pitch is kind of a mystery. (However, there are some known dogs and frogs with perfect pitch)

For anyone who might not know what perfect pitch is: Absolute pitch (AP), often called perfect pitch, is a rare ability of a person to identify or re-create a given musical note without the benefit of a reference tone. - Wikipedia

Most people, even musicians, don't know that this talent exists. When I was in high school, there was someone who has this skill. He had started music when he was a very little. Most perfect pitch persons starts their music in their early ages. This person in my school "senses" pitches (I think it's similar to how we see colors.)

THERE'S NO KNOWN CASES OF ANY ADULT DEVELOPING PERFECT PITCH. There's a number of studies saying it cannot be developed as an adult.

However, I'm doing research for a few months and trying to develop perfect pitch myself (I have a fine relative pitch). None has worked for now. I strongly believe there must be a way for adults to develop this.

My thoughts on this app: It may help to improve something called "tone identification", but that instinct of having perfect pitch is completely different.

By the way, anyone here have perfect pitch (possibility is 1/10000)?

(For any one interested, search Youtube for perfect pitch. There's a lot of fascinating stories)

Hi,

Thanks for the answer. In our MYSQL database, we wanted to count number of pageviews for each website. So, the query was like

SELECT COUNT(id) FROM page_views WHERE website_id = x AND created_at > (start of the month)

For some websites, there are 20 million+ pageviews for each month. MYSQL goes through all of those 20 million rows (according to EXPLAIN) even with index or composite index (It took a few seconds). So, we had to pre-calculate the number of pageviews each hour and show it to the user. Then, things were worst when we had to show analytics. There we had to group by month or day. So, it took more time.

That's when we started finding a solution. And, I learned that there's something called "Analytical Databases", which are designed for those analytics purposes. How they work is completely different from MYSQL.

And, here's a benchmark on MYSQL vs Clickhouse. http://mafiree.com/blogs.php?ref=Benchmark-::-MySQL-Vs-Colum...

MYSQL does a pretty good job for many things. However, when it comes to analytics, I think it's better to use an analytical database.

As each of your users has its own database, there won't be any issues at all. In our case, all of our clients' pageviews are stored in one table, which grows at 35m records per month.

We're also new to this analytical databases thing. I'd like to know your thoughts. :)

Hi. I'm surprised that you have run this platform for 8 years. That's incredible!

There's one question I want to ask you. Do you have any experience handling millions of traffic? I saw that you are using MYSQL for storage. I assume each pageview is stored in a row. So, from my experience MYSQL is very slow performing aggregated queries on those datasets (We recently moved to Clickhouse due to this). I'd like to know your experiences on handling millions of rows in MYSQL, if you have any :)

We actually use two $$ to start and end.

Ex: $$ c = \pm\sqrt{a^2 + b^2} $$

Or, multiline $$ \frac{1}{\Bigl(\sqrt{\phi \sqrt{5}}-\phi\Bigr) e^{\frac25 \pi}} = 1+\frac{e^{-2\pi}} {1+\frac{e^{-4\pi}} {1+\frac{e^{-6\pi}} {1+\frac{e^{-8\pi}} {1+\cdots} } } } $$

Some details are available [in this post](https://talk.hyvor.com/blog/introducing-katex-embed/) on how it works.

And, katex.renderToString has an option to set throwOnError: false.. So, whenever if the TeX code inside $$ is not valid, it just returns the text.

We use this with markdown. Basically, we extended our markdown parser to parse anything between two $$ tags as KaTeX. It was really easy to implement. And, KaTeX is much faster than other alternatives we tested (Yes, that's what title says :) )

Hey!

I cannot imagine how this coincide. An hour ago, I added comments to the homepage. However, I added it to the bottom of the page. As you say, it would be better if I add it to the top.

Thank you very much!